Hydraulic Preventive Maintenance Schedule - … Door Hydraulic Preventive Maintenance Schedule Make several copies of this schedule and keep them handy for performing regular maintenance

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Bin Door Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date The Bin Door hydraulic system is quite simple and should require very little maintenance. Unless problems are encountered, maintenance will mostly include filter changes and oil changes. The filter should be changed on a scheduled basis. Record the date of the last filter change here and on the filter. Date of last filter change Check the breather cap. The breather cap on the Bin Door is the spring type. It should be checked and cleaned at least monthly and replaced annually. If it is not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather.

p

Breather Cap Clean? Date Last Replaced

Breather Ca

Board Jump Chain Outfeed Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since the Board Jump Chain Outfeed uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:

• Case drain flow – measure case flow to determine if the pump is worn • Pump compensator valve – disassemble the valve to ensure that the spool

is not stuck, the orifice in the spool is clear and the spring is not bent or broken.

• Compensator setting – the pump compensator should be set 200 PSI above the pressure required to move the heaviest load.

• The volume stop may be out of adjustment. Turn the volume stop counterclockwise to increase the maximum flow of the pump, clockwise to decrease.

• Synchronization of flow controls in the system – if one or more of the system flow controls is open too wide, its associated actuator can move too rapidly and rob flow from other actuators in the system.

• Plugged suction strainer – this will be accompanied by cavitation (see below).

• Relief valve stuck open Max PSI Min PSI

e

Presare low resuthe follo

12

34567

Breather

sures should be set regularly on this machine, particularly when problemencountered but at least quarterly when seasons change. Pressures set twill result in stalls when moving heavy loads. Pressures set too high wlt in excess force as actuators are deadheaded. This will greatly increashock in the system and eventually show up as leaks. The procedure is ws:

) Place the heaviest load the machine will be expected to move. ) As the load is moving, reduce the pressure by turning the pum

compensator counterclockwise until the load stalls. ) Record the pressure at which the system stalls. ) Shut the machine down. ) Turn the system relief valve counterclockwise to a very low pressure. ) Turn the pump compensator clockwise to a very high pressure. ) Restart the machine – fluid should now be dumping across the syste

relief at a very low pressure.

Relief Valv

Case Drain
Return Filter
Volume Stop

Compensator Valve

s oo ill

se as

p

m

8) Turn the system relief valve clockwise until it is dumping at 450 PSI above the pressure recorded in step 3.

9) Turn the pump compensator counterclockwise to reduce the pressure to 200 PSI above the pressure recorded in step 3.

Listen to the sound of the pump. A steady high pitched whining sound is evidence of cavitation. Cavitation occurs when the pump is unable to draw as much fluid as it is attempting to deliver. This can occur if the suction strainer is plugged or if the oil is too cold and the viscosity is too high. If there is a more erratic high pitched whine that changes in pitch with changes in the machine, the pump may be aerating. Aeration occurs when outside air is introduced into the suction side of the pump. An air leak in the suction line is usually the cause. Squirt oil the length of the suction line. An interruption in the aeration will locate the air leak. When a pump is aerating, there is often a sound similar to marbles rattling inside the pump and foaming of the oil may also be present. OK Cavitating Aerating Check the pump case flow. Do this by measuring the temperature of the suction line and the case drain line with a temperature gun. Work the following formula to determine case flow:

(TCase Drain Line - TSuction Line)

PSI X .0093 Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow Check the temperature of the relief valve tank line. The tank line of the Board Jump Chain Outfeed relief valve should never be hot. If it is, either it has become stuck open or it is improperly adjusted with respect to the pump compensator. The proper setting of the system relief is 250 PSI above that of the compensator. Relief Valve Temperature Check the return line filter. This filter should be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by

the reading of the dirt indicator. The date of the last filter change should be recorded here and on the filter. Date Of Last Filter Change Check the breather cap. The breather cap on the Board Jump Chain Outfeed is the spring type. It should be checked and cleaned at least monthly and replaced annually. If it is not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather. Breather Cap Clean? Date Last Replaced Record the oil temperature. While it is normal for the oil temperature to increase whenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:

• System relief valve • Internally in the pump (check the pump case drain) • The compensator may have been set above the relief valve. • Directional valve spools • Actuators

The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below:

Inspect the hoses in the system. Are any of them rubbing on another hose, part of the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. Inspect the pipe clamps. Proper hydraulic clamps should be used – conduit and beam clamps are unacceptable. Proper clamps? Properly spaced (approximately every 5’ and within 6” of a termination)? List any other problems you have noticed that should be addressed:

Cant Runaround Jump Chain Outfeed Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since the Cant Runaround Jump Chain Outfeed uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:







• Relief valve stuck open Max PSI Min PSI

Volume Stop

Case Drain

Compensator

Pressures should be set regularly on this machine, particularly when problems are encountered but at least quarterly when seasons change. Pressures set too low will result in stalls when moving heavy loads. Pressures set too high will result in excess force as actuators are deadheaded. This will greatly increase the shock in the system and eventually show up as leaks. The procedure is as follows:

1) Place the heaviest load the machine will be expected to move. 2) As the load is moving, reduce the pressure by turning the pump

compensator counterclockwise until the load stalls. 3) Record the pressure at which the system stalls. 4) Shut the machine down. 5) Turn the system relief valve counterclockwise to a very low pressure. 6) Turn the pump compensator clockwise to a very high pressure. 7) Restart the machine – fluid should now be dumping across the system

relief at a very low pressure. 8) Turn the system relief valve clockwise until it is dumping at 450 PSI above

the pressure recorded in step 3. 9) Turn the pump compensator counterclockwise to reduce the pressure to

200 PSI above the pressure recorded in step 3.

e

Listen to the sound of the pumpevidence of cavitation. Cavitationmuch fluid as it is attempting to deplugged or if the oil is too cold anerratic high pitched whine that chapump may be aerating. Aeration suction side of the pump. An air

System Relief Valv

. A steady high pitched whining sound is occurs when the pump is unable to draw as liver. This can occur if the suction strainer is d the viscosity is too high. If there is a more nges in pitch with changes in the machine, the occurs when outside air is introduced into the leak in the suction line is usually the cause.

Squirt oil the length of the suction line. An interruption in the aeration will locate the air leak. When a pump is aerating, there is often a sound similar to marbles rattling inside the pump and foaming of the oil may also be present. OK Cavitating Aerating Check the pump case flow. Do this by measuring the temperature of the suction line and the case drain line with a temperature gun. Work the following formula to determine case flow:

(TCase Drain Line – TSuction Line)

PSI X .0093

Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow Check the temperature of the relief valve. The tank line of the Cant Runaround Jump Chain Outfeed relief valve is not exposed, but the valve itself should be no hotter than the pressure port outlet of the pump. If it is, either it has become stuck open or it is improperly adjusted with respect to the pump compensator. The proper setting of the system relief is 250 PSI above that of the compensator. Relief Valve Temperature Check the return line filter. This filter should be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by the reading of the dirt indicator. The date of the last filter change should be recorded here and on the filter. Date Of Last Filter Change Check the breather cap. The breather cap on the Cant Runaroundshould be checked and cleaned at l

Return Filter

Jump Chain Outfeed is theeast monthly and replaced a

Breather Cap

spring type. It nnually. If it is

not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather. Breather Cap Clean? Date Last Replaced Record the oil temperature. While it is normal for the oil temperature to increase whenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:


The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below:


Debarker Hydraulic Preventive Maintenance Schedule Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since the Debarker uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:






• Relief valve stuck open Max PSI Min PSI Pressures should be set regularly on this machine, particularly when problems are encountered but at least quarterly when seasons change. Pressures set too low will result in stalls when moving heavy loads. Pressures set too high will result in excess force as actuators are deadheaded. This will greatly increase the

Compensator

Case Drain

shock in the system and eventually show up as leaks. The procedure is as follows:





200 PSI above the pressure recorded in step 3. Listen to the sound of the pump. A steady high pitched whining sound is evidence of cavitation. Cavitation occurs when the pump is unable to draw as much fluid as it is attempting to deliver. This can occur if the suction strainer is plugged or if the oil is too cold and the viscosity is too high. If there is a more erratic high pitched whine that changes in pitch with changes in the machine, the pump may be aerating. Aeration occurs when outside air is introduced into the suction side of the pump. An air leak in the suction line is usually the cause. Squirt oil the length of the suction line. An interruption in the aeration will locate the air leak. When a pump is aerating, there is often a sound similar to marbles rattling inside the pump and foaming of the oil may also be present. OK Cavitating Aerating Check the pump case flow. Do this by measuring the temperature of the suction line and the case drain line with a temperature gun. Work the following formula to determine case flow:


PSI X .0093

Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow

Check the temperature of the relief valve. Since the Debarker relief valve is mounted in the valve manifold, its the valve itself should be no hotter than the pressure line near the pump. If it is, either it has become stuck open or it is improperly adjusted with respect to the pump compensator. The proper setting of the system relief is 250 PSI above that of the compensator.

tank line cannot be isolated

elief Valve Temperature

heck the accumulator precharge. In the absence o

op 1/3 hotter than bottom 2/3?

urrent precharge

heck the return line filter. This filter

to measure it, but

e

R Crecommendations, our recommendation is to set the accumulator half of the compensator setting. The precharge should be set with shut down and the accumulator dump valve open. If set properly, the accumulator will fill with oil during operation and the nitrogen will compress to one third its original size. Heat should therefore be felt two thirds of the way up the accumulator and the top one third should be cooler. Precharge should be checked monthly. T C Cshould be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by the reading of the dirt indicator. The date of the last filter change should be recorded here and on the filter.

Relief Valv

f designer precharge to the machine

Date Of Last Filter Change

heck the breather. The breather on the

reather Cap Clean?

ate Last Replaced

ecord the oil temperature.

• System relief valve p (check the p

he source of the excess heat can be d

CDebarker is an element type with no dirt indicator. It should be checked and cleaned at least monthly and replaced at least every six months. If it is not replaced regularly, it can become plugged and either unfiltered air can enter from some other point or the pump could be damaged. Record the date when the breather was last replaced here and on the breather. B D

RWhile it is normal for the oil temperature to increase whenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:

• Internally in the pum• The compensator may have been s• Directional valve spools • Actuators

TThis is best done shortly after startup bthroughout the system. Under no circumallowed to exceed 140oF. Above this temto break down and leave varnish deposits

Level Indicator With Thermometer

ump case drain) f valve.

etermined using the temperature gun.

et above the relie

efore overheated oil can be circulated stances should the oil temperature be perature, most hydraulic oils will begin

.

Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below. Inspect the hoses in the system. Are any of them rubbing on another hose, part of the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. Inspect the pipe clamps. Proper hydraulic clamps should be used – conduit and beam clamps are unacceptable. Proper clamps? Properly spaced (approximately every 5’ and within 6” of a termination)? List any other problems you have noticed that should be addressed:

Dip Tank Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date The Dip Tank hydraulic system is quite simple and should require very little maintenance. Unless problems are encountered, maintenance will mostly include filter changes and oil changes. The filter should be changed on a scheduled basis. Record the date of the last filter change here and on the filter. Date of last filter change Check the breather cap. The breather cap on the Dip Tank is the spring type. It should be checked and cleaned at least monthly and replaced annually. If it is not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather. Breather Cap Clean? Date Last Replaced

Checkvalve hot. Iopen procevalve

1) 2) 3)

Check List an

Relief Valve

the temperature of the relief tank line. It should never be f it is, it may either be stuck or out of adjustment. The

dure for adjusting the relief is as follows:

Deadhead the flow so that fluid dumps across the relief valve Install a pressure gauge upstream of the relief Turn the system on and adjust the relief valve until the heaviest load stalls. Record the pressure. Increase the pressure 200 PSI above that amount.

for leaks and list them here:

y other problems that need to be addressed:

Edger Hydraulic Preventive Maintenance Schedule

The Edger hydraulic power supply has two pressure compensating pumps connected in parallel. There are two schools of thought about the proper pressure settings for these pumps. Both have merit. The first is to set both pumps to identical pressures. This causes both pumps to stroke at the same time and wear evenly. If this is the method used, both pumps should operate at about the same temperature and should sound about the same. The second is to set the pressures 75 – 100 PSI apart. When this is done, the pump set highest will do most of the work. The pump set at the lower pressure will remain de-stroked most of the time and will suffer minimum wear. It will output only when the system demands flow from it as evidenced by a pressure. At any time during operation, it can be determined if stroking by observing the pressure gauge. The checks listed bperformed at least monthly. Make several copies of this schedulehandy for performing regular maintenance checks. Date Observe the machine operation and record the minimum operating pressures. Since the Edger uses pressure compensapressure should not vary significantly during operation. A sharp d(more than 100 – 200 PSI) during a cycle is indicative of a flow prcheck in this case include:

• Case drain flow – measure case flow to determine if the pu• Pump compensator valve – disassemble the valve to ensu

is not stuck, the orifice in the spool is clear and the sprinbroken. If the pressures are set identically, the trouble cocompensator. If they are set apart, it can be determined wthe stuck compensator or is severely worn by observing sIf system pressure is normal except for when flow demandthe problem is with the pump set at the lower press

Compensator

Case Drain

drop in system both pumps are elow should be and keep them

and maximum ting pumps, the rop in pressure

oblem. Items to

mp is worn re that the spool g is not bent or uld be in either hich pump has

ystem pressure. s are high, then ure. If system

pressure is 75 – 100 PSI below normal before it drops out, the problem is with the pump set at the higher pressure.

• Compensator setting – the pump compensators should be set 200 PSI above the pressure required to move the heaviest load if their settings are identical. If they are set apart, the lower pressure setting should be 200 PSI above maximum load pressure and the higher setting should be 275 – 300 PSI above maximum load.



• Relief valve stuck open Max PSI Min PSI Pressures should be set regularly on this machine, particularly when problems are encountered but at least quarterly when seasons change. Pressures set too low will result in stalls when moving heavy loads. Pressures set too high will result in excess force as actuators are deadheaded. This will greatly increase the shock in the system and eventually show up as leaks. In the absence of designer recommendations, we recommend that the lower setting of the pump compensators be set 200 PSI above the maximum load pressure, the higher setting 75 PSI above the lower and the system relief 250 PSI above the higher compensator setting. If the pumps are pressures, isolate the pumps from each other before makinPumps can be damaged by turning them backwards. If the pumfrom each other, isolate the pump that is to be set at the higher pthe lower pressure first. Then set the higher pressure. The follows:

e

1) Place the heaviest load the machine will be expected to mo2) As the load is moving, reduce the pressure by tur

compensator counterclockwise until the load stalls. 3) Record the pressure at which the system stalls. 4) Shut the machine down.

Relief Valv

set to identical g adjustments. ps are set apart ressure and set procedure is as

ve. ning the pump

5) Turn the system relief valve counterclockwise to a very low pressure. 6) Turn the pump compensator clockwise to a very high pressure. 7) Restart the machine – fluid should now be dumping across the system



200 PSI above the pressure recorded in step 3. Listen to the sound of each pump. A steady high pitched whining sound is evidence of cavitation. Cavitation occurs when the pump is unable to draw as much fluid as it is attempting to deliver. This can occur if the suction strainer is plugged or if the oil is too cold and the viscosity is too high. If there is a more erratic high pitched whine that changes in pitch with changes in the machine, the pump may be aerating. Aeration occurs when outside air is introduced into the suction side of the pump. An air leak in the suction line is usually the cause. Squirt oil the length of the suction line. An interruption in the aeration will locate the air leak. When a pump is aerating, there is often a sound similar to marbles rattling inside the pump and foaming of the oil may also be present. OK Cavitating Aerating Check the pump case flow. Do this by measuring the temperature of the suction line and the case drain line with a temperature gun. Work the following formula to determine case flow:


PSI X .0093 Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow Check the temperature of the relief valve. Since the tank line of the valve is not exposed, temperature must be measured at the valve itself. The relief valve should be no hotter than the pressure port of the pump. If it is, either it has become stuck open or it is improperly adjusted with respect to the pump compensators. The proper setting of the system relief is 250 PSI above that of the compensators (or of the higher set compensator if the pumps are set apart). Relief Valve Temperature

Check the accumulator precharge. In the absence of designer recommendations, our recommendation is to set the accumulator precharge to half of the higher compensator setting. The precharge should be set with the machine shut down and the accumulator dump valve open. If set properly, the accumulator will fill with oil during operation and the nitrogen will compress to one third its original size. Heat should therefore be felt two thirds of the way up the accumulator and the top one third should be cooler. Precharge should be checked monthly. Top 1/3 hotter than bottom 2/3? Current precharge

Check the temis functioning pIf there is onlya portion of thbadly plugged,An air cooler c Temperature D Good Air Flow Cooler Pressu

Cooler Inlet

e

perature of throperly, the o

a small differe cooler has a significant an rupture if t

rop Between

?

re Gauge Rea

Cooler Fins Must Stay Clear

e inlet and the outlet lines of theutlet line should be significantly

ence, either the cooler does not become partially plugged. If pressure drop will be noted on the pressure drop across it excee

Cooler Inlet and Cooler Outlet

ding

Cooler Gaug

Cooler Outlet

cooler. If the cooler cooler than the inlet. have good air flow or the cooler becomes

he gauge at the inlet. ds 150 – 200 PSI.

The recirculating cooling and filtering pump is a fixed displacement gear pump and should require minimal maintenance. The best indication of its performance is the current draw of the electric drive motor. When the pump is bypassing severely, it will draw significantly less current. Measure the current draw of the drive motor with an ammeter while the pump is functioning properly. Current Draw Check the return line, recirculating and pressure filters. These filters should be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by the reading of the dirt indicator. This is especially important on the edger because of the extremely tight tolerances of the valves. An oil sample port is mounted on the side of the reservoir. To begin an oil analysis schedule, start at 13-week intervals and adjust the time between samples according to the results. Filters should all be changed at the same time. The date of the last filter change should be recorded here and on the filter. Date Of Last Filter Change Check the breather cap. The breather cap on the Edger is an element type. It should be checked monthly to make sure the indicator is not stuck and replaced whenever the indicator shows red. Record the date when the breather was replaced here and on the breather. Breather Indicator OK? Date Last Replaced

Record the oil temperature. While it is normal for the oil temperature to increase whenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:

• System relief valve • Internally in one of the pumps (check the pump case drains and current

draw on the recirculating pump) • One of the compensators may have been set above the relief valve. • Valve spools • Actuators

The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Oil Temperature Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below. Inspect the hoses in the system. Are any of them rubbing on another hose, part of the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. Inspect the pipe clamps. Proper hydraulic clamps should be used – conduit and beam clamps are unacceptable. Proper clamps? Properly spaced (approximately every 5’ and within 6” of a termination)?

List any other problems you have noticed that should be addressed:

Gang Saw Hydraulic Preventive Maintenance Schedule

There are two identical Gang Saw units. The sound and operating temperatures of both units should remain similar. If either machine begins to make sounds that the other does not or begins to operate at a higher temperature than the other, this should be cause for concern. The checks listed below should be performed at least monthly on each machine. Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since the Gang Saw uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure during a cycle is indicative of a flow problem. Items to check in this case include:






• Relief valve stuck open Max PSI Min PSI Pressures should be set regularly on this machine, particularly when problems are encountered but at least quarterly when seasons change. Pressures set too low will result in stalls when moving heavy loads. Pressures set too high will result in excess force as actuators are deadheaded. This will greatly increase the shock in the system and eventually show up as leaks. The procedure is as follows:







(T Case Drain Line – T Suction Line)

PSI X .0093 Where “PSI” is the system operationg pressure. The result will beof the pump in gallons per minute. A relatively new pump shoumore than about 1 – 3% of its total output. If the pump flow is rmuch as 10%, it should usually be replaced. Case Flow

Case Drain

thlded

Suction Line

e case flow bypass no uced by as

Check the temperature of the relief valve. The Gang Saw relief valve is mounted on the directional valve manifold, so its tank line cannot be measured. The relief valve should be no hotter than surrounding components. Relief Valve Temperature

Measure Temperature

Difference

n

Check the temperature of the inlet and the outlet lines of the coois functioning properly, the outlet line should be significantly cooIf there is only a small difference, either the cooler does not havea portion of the cooler has become plugged. Since there is nvalve, a plugged cooler can easily rupture. A pressure drop acr150 – 200 PSI can rupture it. Temperature Drop Between Cooler Inlet and Cooler Outlet Good Air Flow? Check the return line filter. This filter should be checked anscheduled basis. The filter schedule should be determined by date of the last filter change should be recorded here and on the Date Of Last Filter Change Check the dirt indicator on the breather. When the indicator shows red, the breather cap should be replaced. Record the date when the breather was replaced here and on the breather.

Breather Dirt Indicator

Indicator OK? Date Of Last Breather Change

Keep Cooler Fins Clea

ler. If the cooler ler than the inlet. good air flow or o bypass check oss the cooler of

d changed on a oil analysis. The filter.



The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Oil Temperature Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below: Inspect the hoses in the system. Are any of them rubbing on another hose, part of the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. Inspect the pipe clamps. Proper hydraulic clamps should be used – conduit and beam clamps are unacceptable. Proper clamps? Properly spaced (approximately every 5’ and within 6” of a termination)?

List any other problems you have noticed that should be addressed:

Head Saw Setworks Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since the Head Saw Setworks uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:








Compensator

Case Drain

Suction Line

Volume Stop


compensator counterclockwise until the load stalls. The Head Saw Setworks uses a Rexroth Pressure Compensating pump with a dual compensator assembly. The second compensator is for a load sensing package that is not installed. Make all adjustments to the inner compensator. The compensator valve farther from the pump body (the one on top) should be kept turned fully clockwise.

3) Record the pressure at which the system stalls. 4) Shut the machine down. 5) Turn the system relief valve counterclockwise to a very low pressure. 6) Turn the pump compensator cloc

Restart the machine – fluid should n

kwise to a very high pressure. 7)

ow be dumping

8) dumping at

9) o reduce

isten to the sound of the pump. A s

K Cavitating Aerating

across the system relief at a very low pressure. Turn the system relief valve clockwise until it is 450 PSI above the pressure recorded in step 3. Turn the pump compensator counterclockwise tthe pressure to 200 PSI above the pressure recorded in step 3.

Levidence of cavitation. Cavitation occursmuch fluid as it is attempting to deliver. Tplugged or if the oil is too cold and the verratic high pitched whine that changes in pump may be aerating. Aeration occurs suction side of the pump. An air leak inSquirt oil the length of the suction line. Athe air leak. When a pump is aerating, thrattling inside the pump and foaming of the O

System Relief Valve

teady high pitched whining sound is

when the pump is unable to draw as his can occur if the suction strainer is

iscosity is too high. If there is a more pitch with changes in the machine, the when outside air is introduced into the the suction line is usually the cause. n interruption in the aeration will locate ere is often a sound similar to marbles oil may also be present.

Check the pump case flow. Do this by measuring the temperature of the suction line and the case drain line with a temperature gun. Work the following formula to determine case flow:


PSI X .0093 Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow Check the temperature of the relief valve. The tank line of the Head Saw Setworks relief valve is not exposed, but the valve itself should be no hotter than the pressure line of the pump. If it is, either it has become stuck open or it is improperly adjusted with respect to the pump compensator. The proper setting of the system relief is 250 PSI above that of the compensator. Relief Valve Temperature

heck the temperature of the inlet and the outlet lin functioning properly, the outlet line should be sig there is only a small difference, either the cooler portion of the cooler has become partially plugadly plugged, it could become ruptured.

emperature Drop Between Cooler Inlet and Coole

ood Air Flow?

Record Temperature

Difference

CisIfab T G

Fins Must Be Kept Clean

es of the cooler. If the cooler nificantly cooler than the inlet. does not have good air flow or ged. If the cooler becomes

r Outlet

The recirculating cooling and filtering pump is a fixed displacement gear pump and should require minimal maintenance. The best indication of its performance

lectric drive motor. When bypassing

everely, it will draw ignificantly less current. easure the current draw of

checked

leaned

unfiltered

is the current draw of the ethe pump isssMthe drive motor with an ammeter while the pump is functioning properly. Current Draw

Check th

determinfilters at here and Date Of L Check thHead Sano dirt incleast everegularlythe syste

Return Line Filter IndicatorWith Dirt

and changed on a scheduled basis. T

n

at least monthly and replaced at

, contaminated air) or the pump may

e return line filter and the pre

ed by oil analysis, not by the readithe same time. The date of the last filt on the filters.

ast Filter Change

he breather ow Setworks is an element type with dicator. It should be checked and

ssure filt

ng of the

the e breather. T

ry six months. If it is not replaced , it can plug and either air will enter m from some other point (bringing in

Pressure Filter

he filter schedule should be er. These filters should be

e dirt indicator. Change both r change should be recorded

suffer damage. At the next breather change, a breather with a dirt indicator should be considered. Record the date when the breather was replaced here nd on the breather.

reather Clean?

or the oil temperature to increase

ing may be occurring can include:

ase drain)

• Actuators

he source of the excess heat can be determined using the temperature gun. ortly after startup before overheated oil can be circulated

roughout the system. Under no circumstances should the oil temperature be

il Temperature Ch l is low, there mu b

il Level

a B Date Last Replaced Record the oil temperature. While it is normal fwhenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypass

• System relief valve • Internally in the pump (check the pump c• The compensator may have been set above the relief valve. • Directional valve spools

TThis is best done shthallowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. O

eck the oil level (with any cylinders fully retracted). If the oil levest e a leak in the system.

O Inspect for leaks in the system and list below.


Infeed Jump Chain Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since the Infeed Jump Chain uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:




• Volume stop adjustment – turn the adjustment clockwise to reduce the maximum output of the pump, counterclockwise to increase it.




e

1) Place the heaviest load the machine will be expected to m

Suction Lin

Compensator

ov

Case Drain

e.

2) As the load is moving, reduce the pressure by turning the pump compensator counterclockwise until the load stalls.

3) Record the pressure at which the system stalls. 4) Shut the machine down. 5) Turn the system relief valve counterclockwise to a very low pressure. 6) Turn the pump compensator clockwise to a very high pressure. 7) Restart the machine – fluid should now be dumping across the system





PSI X .0093 Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow Check the temperature of the relief valve. Since the relief valve of the Infeed Jump Chain is in the valve manifold, it shares a tank line with the directional valves and cannot be isolated to measure temperature. The valve itself, however, should never be hotter than the pressure line near the pump. If it is, either it has become stuck open or it is improperly adjusted with respect to the

pump compensator. The proper setting of the system relief is 250 PSI above that of the compensator. Relief Valve Temperature Check the return line filter. This filter should be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by the reading of the dirt indicator. The date of the last filter change should be recorded here and on the filter. Date Of Last Filter Change Check the breather cap. The breather cap on the Infeed Jump Chain is the spring type. It should be checked and cleaned at least monthly and replaced annually. If it is not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather. Breather Cap Clean? Date Last Replaced Record the oil temperature. While it is normal for the oil temperature to increase whenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:


The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be

allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Oil Temperature

Check Difference In Temperature

Check the difference in temperature between thcooler. There should be a noticeable differenproperly. If the difference is only slight, the coolthe cooler becomes badly plugged, it could ruptudifference at all, the trouble could be the air flow tair cooler to operate efficiently, you must be able t Difference in temperature between inlet and outlet Good air flow? Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below:

Fins Must Be Kept Clear

e inlet and outlet lines of the ce if the cooler is functioning er may be partially plugged. If re. If there is no temperature

hrough the fins. In order for an o see daylight through the fins.


Linear Positioner Unit Infeed Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since the Linear Positioner Unit Infeed uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:




• Volume stop adjustment – turn the adjustment clockwise to reduce the maximum output of the pump, counterclockwise to increase it.




1) Place the heaviest load the machine will be expected to move

Compensator

.

Case Drain

Suction Line







PSI X .0093

Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow Check the temperature of the relief valve. Since the relief valve of the Linear Positioner Unit Infeed is in the valve manifold, it shares a tank line with the directional valves and cannot be isolated to measure temperature. The valve itself, however, should never be hotter than the pressure line near the pump. If it is, either it has become stuck open or it is improperly adjusted with respect to the

pump compensator. The proper setting of the system relief is 250 PSI above that of the compensator. Relief Valve Temperature

Measure Temperature

Difference

Check the temperature of the inlet and the outlis functioning properly, the outlet line should beIf there is only a small difference, either the cooa portion of the cooler has become partially badly plugged, it is possible that the cooler cou Temperature Drop Between Cooler Inlet and C Good Air Flow? Check the return line filter. This filter should bechecked and changed on a scheduled basisThe filter schedule should be determined by oianalysis, not by the reading of the dirt indicatorThe date of the last filter change should berecorded here and on the filter. Date Of Last Filter Change


et lines of the cooler. If the cooler significantly cooler than the inlet. ler does not have good air flow or plugged. If the cooler becomes

ld rupture.

ooler Outlet

. l .

Check the breather cap. The breather cap on the Linear Positioner Unit Infeed is the spring type. It should be checked and cleaned at least monthly and replaced annually. If it is not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather. Breather Cap Clean? Date Last Replaced Record the oil temperature. While it is normal for the oil temperature to increase whenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:


The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Oil Temperature Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below:


Log Turner Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. The Log Turner uses fixed displacement pumps and unloads the flow through the directional valves when it idles. The pressure should drop very near 0 PSI at idle and build to a pressure proportional to the weight of the load during operation. Significant drops in pressure (more than 100 – 200 PSI) coupled with load stalling during operation indicate a flow problem. Possible causes can include:

• Internal pump bypassing • Contaminated check valves in the “P” ports of one or more of the

directional valves • Accumulator precharge or ruptured bladder • Plugged suction strainer – this will be accompanied by cavitation (see

below). • Relief valve stuck partially open or improperly set

Max PSI Min PSI Pressures should be set regularly on this machine, particularly when problems are encountered but at least quarterly when seasons change. Pressures set too low will result in stalls when moving heavy loads. Pressures set too high will result in excess force as actuators are deadheaded. This will greatly increase the shock in the system and eventually show up as leaks. The procedure is as follows:

1) Place the heaviest load the machine will be expected to move. 2) As the load is moving, observe the highest pressure reached on the gauge 3) Shut the machine down 4) Deadhead the flow so that the only path back to tank is through the relief

valve 5) Turn the relief counterclockwise to a very low pressure and start the

machine 6) Gradually increase the relief valve setting until the pressure reading is 200

PSI above the pressure observed in step 2 Listen to the sound of the pump. A steady high pitched whining sound is evidence of cavitation. Cavitation occurs when the pump is unable to draw as

much fluid as it is attempting to deliver. This can occur if the suction strainer is plugged or if the oil is too cold and the viscosity is too high. If there is a more erratic high pitched whine that changes in pitch with changes in the machine, the pump may be aerating. Aeration occurs when outside air is introduced into the suction side of the pump. An air leak in the suction line is usually the cause. Squirt oil the length of the suction line. An interruption in the aeration will locate the air leak. When a pump is aerating, there is often a sound similar to marbles rattling inside the pump and foaming of the oil may also be present. OK Cavitating Aerating Measure the temperature of the pump case. If the pumps are bypassing internally, there will be an increase in pump case temperature. A measurement while the pump is functioning properly can be a good benchmark. Another strong indication of pump wear is the current draw of the drive motor. Since it is easier to turn a pump with worn clearances, there will be a drop in current draw as the pump wears. Since the load changes, be sure to always measure at the same load pressure. Case Temperature

urrent Draw

heck the temperature of the relief valve

elief Valve Tank Line Temperature

C Ctank line. The tank line of the Log Turner relief valve should never be hot. If it is, either it has become stuck open or it is improperly adjusted. The proper setting of the system relief is 200 PSI above that of the pressure required to move the heaviest load. R

Measure Temperature

Difference

Check the temperature of the inlet and the outletis functioning properly, the outlet line should be If there is only a small difference, either the coolea portion of the cooler has become partially pbadly plugged, it is possible that the cooler could Temperature Drop Between Cooler Inlet and Coo Good Air Flow?

Check the return line filter and the pressure checked and changed on a scheduled basis. determined by oil analysis, not by the readinreplacing filters, replace them both at the samechange should be recorded here and on the filter Date Of Last Filter Change


lines of the cooler. If the cooler significantly cooler than the inlet. r does not have good air flow or

lugged. If the cooler becomes rupture.

ler Outlet

Return Filter With Dirt Indicator

filter. These f The filter scheg of the dirt in time. The date.

Pressure Filter

ilters should be dule should be dicator. When of the last filter

Check the breather. The breather on the Log Turner is an element type with no dirt indicator. It should be checked and cleaned at least monthly and replaced at least every six months. If it is not replaced regularly, it can plug and unfiltered air can enter the reservoir from some other point such as the access plates. Pump damage can also result from a plugged breather. Record the date when the breather was replaced here and on the breather. Breather Clean? Date Last Replaced Record the oil temperature. While it is normal for the oil temperature to increase whenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:

• System relief valve • Internally in the pump (check the pump case temperature and current

draw) • Directional valve spools • Actuators

The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Oil Temperature Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Check the accumulator precharge at least monthly. In the absence of designer recommendations, we recommend that the accumulator be precharged with dry nitrogen to half of the relief valve setting. Feel the sides of the shell. If the accumulator is functioning properly, the nitrogen will be compressed to one third its original size during operation. Since nitrogen does not conduct heat very well, more heat

should be felt on the bottom two thirds than on the top one third. Since the Log Turner accumulator is mounted on its side, the “top” of the accumulator is considered to be the end with the Schrader valve for adjusting precharge. If heat is felt across most of the accumulator shell, it is undercharged. Heat only near the bottom indicates that the accumulator is undercharged. If no heat at all is felt, either the accumulator is precharged above the system pressure or the bladder has ruptured. Where is heat felt? Current precharge Inspect for leaks in the system and list below: Inspect the hoses in the system. Are any of them rubbing on another hose, part of the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. Inspect the pipe clamps. Proper hydraulic clamps should be used – conduit and beam clamps are unacceptable. Proper clamps? Properly spaced (approximately every 5’ and within 6” of a termination)? List any other problems you have noticed that should be addressed:

Resaw Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. For actuators driven by the pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:






• Relief valve stuck open Max PSI Min PSI Pressure in the lines driven by the fixed displacement Lamborghini pump will vary anywhere from 0 PSI to the setting of the relief valve. Since the flow from this pump is unloaded back to tank whenever the arms are not moving, there should not be significant heat buildup. To measure the relief valve setting, fully extend any one of the arms and hold it in position. The setting of the relief valve should appear on the gauge. Record it here. Relief Valve Setting

Pressures should be set regularly on this machine,

(In

1) Place the heavie2) As the load is

compensator cou3) Record the press4) Shut the machine5) Turn the system 6) Turn the pump co7) Restart the mac

relief at a very lo8) Turn the system

the pressure reco9) Turn the pump c

200 PSI above th Listen to the sound ofevidence of cavitation. much fluid as it is attemplugged or if the oil is erratic high pitched whinpump may be aerating.suction side of the puma bad shaft seal can cauoil the length of the sucleak. When a pump is inside the pump and foa OK Cavitating

Relief Valve Valve Manifold)
particularly when problems
are encountered but at least quarterly when seasons change. Pressures set too low will result in stalls when moving heavy loads. Pressures set too high will result in excess force as actuators are deadheaded. This will greatly increase the shock in the system and eventually show up as leaks. The procedure is as follows:

st load the machine will be expected to move. moving, reduce the pressure by turning the pump nterclockwise until the load stalls. ure at which the system stalls. down.

relief valve counterclockwise to a very low pressure. mpensator clockwise to a very high pressure.

hine – fluid should now be dumping across the system w pressure. relief valve clockwise until it is dumping at 450 PSI above rded in step 3. ompensator counterclockwise to reduce the pressure to e pressure recorded in step 3.

the pumps. A steady high pitched whining sound is Cavitation occurs when the pump is unable to draw as pting to deliver. This can occur if the suction strainer is

too cold and the viscosity is too high. If there is a more e that changes in pitch with changes in the machine, the

Aeration occurs when outside air is introduced into the p. An air leak in the suction line is usually the cause, but se the fixed displacement pump to aerate as well. Squirt

tion line. An interruption in the aeration will locate the air aerating, there is often a sound similar to marbles rattling ming of the oil may also be present.

Aerating

Compensator

Case Drain

Suction Line

Volume Stop



PSI X .0093 Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow The fixed displacement pump has no case drain. Instead, measure the current draw of the electric drive motor while the pump is relatively new and use this reading as a benchmark for future checks. This check should be made while the flow is dumping across the relief valve. If the pump is suspected to be bad, divert the flow from the tank line into a container so it can be viewed. Turn the pressure down very low on the relief valve, deadhead the circuit so that oil must

dump across the valve and observe the flow. Even a bad pump will deliver most of its flow at low pressure. Gradually increase the pressure setting of the relief valve and again observe the flow. If increasing the pressure to normal operating pressure results in a significant decrease in flow, the pump is worn and must be replaced. Current Draw Check the temperature of the relief valve tank line. The Resaw relief valve is mounted in the valve manifold. This line will probably be a little warm at times, but should never be excessively hot (above 130oF) If it is, either it has become stuck open or it is improperly adjusted with respect to the pump compensator. The proper setting of the system relief is about 900 PSI. Relief Valve Tank Line Temperature

Check the return line filter. This filter should be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by the reading of the dirt indicator. The date of the last filter change should be recorded here and on the filter. Date Of Last Filter Change

Check the breather cap. The breather cap on the Resaw is the spring type. It should be checked and cleaned at least monthly and replaced annually. If it is not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather. Breather Cap Clean? Date Last Replaced


• System relief valve • Internally in one of the pumps (check the pressure compensating pump

case drain and the current draw of the electric drive motor on the fixed displacement pump)

• The compensator may have been set above the relief valve. • Directional valve spools • Actuators

The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Oil Temperature

Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level

Inspect for leaks in the system and list below:


Sawset Positioner Hydraulic Preventive Maintenance Schedule Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since the Sawset Positioner uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:












Listen to the sound of the pump. A steady high pitched whining sound is evidence of cavitation. Cavitation occurs when the pump is unable to draw as much fluid as it is attempting to deliver. This can occur if the suction strainer is plugged or if the oil is too cold and the viscosity is too high. If there is a more erratic high pitched whine that changes in pitch with changes in the machine, the pump may be aerating. Aeration occurs when outside air is introduced into the suction side of the pump. An air leak in the suction line is usually the cause. Squirt oil the length of the suction line. An interruption in the aeration will locate the air leak. When a pump is aerating, there is often a sound similar to marbles rattling inside the pump and foaming of the oil may also be present. OK Cavitating Aerating

e

Chlinto

Suction Lin

eck the pump case flowe and the case drain lin determine case flow:

Case Drain

e

. Do this by measuring the temperae with a temperature gun. Work the

Relief Valv

ture of the suction following formula


PSI X .0093

Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow Check the temperature of the relief valve tank line. The tank line of the Sawset Positioner relief valve should never be hot. If it is, either it has become stuck open or it is improperly adjusted with respect to the pump compensator. The proper setting of the system relief is 250 PSI above that of the compensator. Relief Valve Temperature Check the return line filter. This filter should be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by the reading of the dirt indicator. The date of the last filter change should be recorded here and on the filter. Date Of Last Filter Change

Check the breather cap. The breather cap on the Sawset Positioner is the spring type. It should be checked and cleaned at least monthly and replaced annually. If it is not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather.

Breather Cap Clean? Date Last Replaced



The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Oil Temperature Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below: Inspect the hoses in the system. Are any of them rubbing on another hose, part of the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. Inspect the pipe clamps. Proper hydraulic clamps should be used – conduit and beam clamps are unacceptable. Proper clamps? Properly spaced (approximately every 5’ and within 6” of a termination)? List any other problems you have noticed that should be addressed:

Skragg Mill Hydraulic Preventive Maintenance Schedule

The Skragg Mill uses a hydrostatic drive. The hydrostatic drive is a closed loop hydraulic system. Unlike conventional hydraulic systems, the hydrostatic drive utilizes a bi-directional pump. The pump is capable of stroking completely from full reverse to full forward as determined by stroking cylinders. A servo valve mounted on the top of the pump controls the stroking cylinders. Oil that is bypassed in the system is replenished by a gear pump mounted at the front of the main pump and turned by the same electric drive motor. System pressure limits are preset internally, effectively emulating a pressure compensating pump. Maintenance and adjustments are intentionally limited by design, thus the underlying causes of hydraulic failures must be adhered to more rigidly to avoid trouble in the first place.

o

The most critical concern is clanalyzed regularly. To beginadjust according to the resultsschedules and oil change sch Date Record the pressure at the gauge of the relief valve while the system is functioning properly. The setting of this valve determines proper replenishment of oil that has bypassed in the system. If the pressure drops too low, not enough oil will be replaced by the replenishing pump and the main pump assembly will suffer damage. Whenever a drop

Replenishing Pump

e a. ed

Serv

anliness of the oil. The oil should ben analysis cycle, start with 13-week Use the results of the analyses to dules.

Inlet and Outlet of Replenishing

Pump – Measure Temperature

Difference

sampled and intervals and etermine filter

from normal pressure is observed, the pressure at the relief should be reset to normal immediately. Pressure Listen to the sound of the pumps. A steady high pitched whining sound is evidence of cavitation. Cavitation occurs when the pump is unable to draw as much fluid as it is attempting to deliver. This can occur if the suction strainer of the replenishing pump is plugged or if the oil is too cold and the viscosity is too high. If there is a more erratic high pitched whine that changes in pitch with changes in the machine, the pump may be aerating. Aeration occurs when outside air is introduced into the suction side of the pump. An air leak in the suction line is usually the cause. Squirt oil the length of the suction line. An interruption in the aeration will locate the air leak. When a pump is aerating, there is often a sound similar to marbles rattling inside the pump and foaming of the oil may also be present. It may be necessary to use a stethoscope to determine which pump is making an improper sound. If the gear pump is cavitating, the source of the cavitation should be located and corrected immediately before the gear pump is destroyed. If left unchecked, damage to the main pump will occur. If the main pump is cavitating, check the temperature of the gear pump. It could be bypassing severely internally and delivering a reduced flow. Record the temperature difference between the inlet and outlet of the gear pump when it is functioning normally to compare when it appears to be bypassing. If the gear pump does not have an increased temperature gain, the problem is likely to be the pressure filter. Main Pump Cavitating Or Aerating? Replenishing Pump Cavitating Or Aerating? Temperature Gain Across Replenishing Pump Since excess replenishing oil is dumped into the main pump case, the flow of the case drain will not be a reliable indication of the condition of the main pump. It is therefore necessary to measure the current draw of the electric drive motor to determine the pump condition. An initial check of the current draw should be

made while the system is functioning properly to be used as a benchmark. Then make monthly checks to track the performance. Checks should be made in five different modes for comparison since the pump is bi-directional and variable displacement: Current Draw At Idle Current Draw At Full Forward under no load Current Draw At Full Forward under full load Current Draw At Full Reverse under no load Current Draw At Full Reverse under full load Check the temperature of the inlet and the outlet lines of the cooler. If the cooler is functioning properly, the outlet line should be significantly cooler than the inlet. If there is only a small difference, either the cooler does not have good air flow or a portion of the cooler has become partially plugged. If the cooler becomes badly plugged, it is possible that the cooler could rupture. Temperature Drop Between Cooler Inlet and Cooler Outlet Good Air Flow?

Check the checked andetermined the last filter Date Of Las Check the bIt should be not replacedmay be cleawhen the bre Breather Ca Date Last Re Record the owhenever ambypassing in

• Relief• Intern• Actua

The source This is bestthroughout tallowed to eto break dow Oil Tempera

Return Filter

return line filter and the pressure filter. d changed on a scheduled basis. The by oil analysis, not by the reading of the change should be recorded here and on th

t Filter Change

reather cap. The breather cap on the Skrchecked and cleaned at least monthly and regularly, the spring can lose its tensionn, it will allow contaminants to enter the rather was replaced here and on the breath

p Clean?

placed

il temperature. While it is normal for the obient temperature does, excessively high

the system. Places where bypassing may

valve ally in the pump (check the current draw otors

of the excess heat can be determined u done shortly after startup before overhehe system. Under no circumstances shoxceed 140oF. Above this temperature, mon and leave varnish deposits.

ture

Pressure Filter

These filters should be filter schedule should be

dirt indicator. The date of e filter.

agg Mill is the spring type. replaced annually. If it is

and, though the cap itself eservoir. Record the date er.

il temperature to increase oil temperature indicates be occurring can include:

f the electric drive motor)

sing the temperature gun. ated oil can be circulated uld the oil temperature be st hydraulic oils will begin

Check the oil level. If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below: Inspect the hoses in the system. Are any of them rubbing on another hose, part of the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. This is a particular problem on the Skragg Mill. Gradual replacement of hoses with hard pipe should be considered. Inspect the pipe clamps. Proper hydraulic clamps should be used – conduit and beam clamps are unacceptable. Proper clamps? Properly spaced (approximately every 5’ and within 6” of a termination)? List any other problems you have noticed that should be addressed:

Skragg Outfeed Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since Skragg Outfeed uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:












Listen to the sound of the pump. A steady high pitched whining sound is evidence of cavitation. Cavitation occurs when the pump is unable to draw as much fluid as it is attempting to deliver. This can occur if the suction strainer is plugged or if the oil is too cold and the viscosity is too high. If there is a more erratic high pitched whine that changes in pitch with changes in the machine, the pump may be aerating. Aeration occurs when outside air is introduced into the suction side of the pump. An air leak in the suction line is usually the cause. Squirt oil the length of the suction line. An interruption in the aeration will locate the air leak. When a pump is aerating, there is often a sound similar to marbles rattling inside the pump and foaming of the oil may also be present. OK Cavitating Aerating

Checkline anto dete

Case Drain

the d thrmin

Compensator

e

pump case flow. Do e case drain line withe case flow:

Suction Lin

this by measuring the temperature of the suction a temperature gun. Work the following formula

(T Case Drain – T Suction Line)

PSI X .0093

Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow

Check the temperature of the relief valve tank line. The tank line of the Skragg Outfeed relief valve should never be hot. If it is, either it has become stuck open or it is improperly adjusted with respect to the pump compensator. The proper setting of the system relief is 250 PSI above that of the compensator. Relief Valve Temperature Check the temperature of the inlet and the outlet lines of the cooler. If the cooler is functioning properly, the outlet line should be significantly cooler than the inlet. If there is only a small difference, either the cooler does not have good air flow or

a portion of the cooler has become partially plugged. If the cooler becomes badly plugged, it is possible that the cooler could rupture. Temperature Drop Between Cooler Inlet and Cooler Outlet Good Air Flow? Check the return line filter. This filter should be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by the reading of the dirt indicator. The date of the last filter change should be recorded here and on the filter. Date Of Last Filter Change

Check the breather cap. The breather cap on the Skragg Outfeed is the spring type. It should be checked and cleaned at least monthly and replaced annually. If it is not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather. Breather Cap Clean? Date Last Replaced Record the oil temperature. While it is normal for the oil temperature to increase whenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:


The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Oil Temperature Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level

Inspect for leaks in the system and list below: Inspect the hoses in the system. Are any of them rubbing on another hose, part of the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. Inspect the pipe clamps. Proper hydraulic clamps should be used – conduit and beam clamps are unacceptable. Proper clamps? Properly spaced (approximately every 5’ and within 6” of a termination)? List any other problems you have noticed that should be addressed:

Star Kicker Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since the Star Kicker uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:













200 PSI above the pressure recorded in step 3. Compensator

(Adjustment At Rear)

LisevimupluerrpusucSqtherat OK

Case Drain

e

ten to the sound of the pump. A steady high pitched whdence of cavitation. Cavitation occurs when the pump is unach fluid as it is attempting to deliver. This can occur if the sugged or if the oil is too cold and the viscosity is too high. If tatic high pitched whine that changes in pitch with changes in thmp may be aerating. Aeration occurs when outside air is introtion side of the pump. An air leak in the suction line is usu

uirt oil the length of the suction line. An interruption in the aer air leak. When a pump is aerating, there is often a sound simtling inside the pump and foaming of the oil may also be presen

Cavitating Aerating

Relief Valve

Suction Lin

Volume Stop

ining sound is ble to draw as

ction strainer is here is a more e machine, the duced into the ally the cause. ation will locate ilar to marbles

t.



PSI X .0093

Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow Check the temperature of the relief valve tank line. The tank line of the Star Kicker relief valve should never be hot. If it is, either it has become stuck open or it is improperly adjusted with respect to the pump compensator. The proper setting of the system relief is 250 PSI above that of the compensator. Relief Valve Tank Line Temperature Check the temperature of the inlet and the outlet lines of the cooler. If the cooler is functioning properly, the outlet line should be significantly cooler than the inlet. If there is only a small difference, either the cooler does not have good air flow or a portion of the cooler has become partially plugged. If the cooler becomes badly plugged, it is possible that the cooler could rupture. Temperature Drop Between Cooler Inlet and Cooler Outlet Good Air Flow?

Check the return line filter. This filter should be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by the reading of the dirt indicator. The date of the last filter change should be recorded here and on the filter. Date Of Last Filter Change

Check the breather cap. The breather cap on the Star Kicker is the spring type. It should be checked and cleaned at least monthly and replaced annually. If it is not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather.

Breather Cap Clean? Date Last Replaced Record the oil temperature. While it is normal for the oil temperature to increase whenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:


The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be

allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Oil Temperature Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below: Inspect the hoses in the system. Are any of them rubbing on another hose, part of the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. Inspect the pipe clamps. Proper hydraulic clamps should be used – conduit and beam clamps are unacceptable. Proper clamps? Properly spaced (approximately every 5’ and within 6” of a termination)? List any other problems you have noticed that should be addressed:

Trim Saw Hydraulic Preventive Maintenance Schedule

There are three identical Trim Saw units. The sound and operating temperatures of all three units should remain similar. If any machine begins to make sounds that another does not or begins to operate at a higher temperature than another, this should be cause for concern. The checks listed below should be performed at least monthly on each machine. Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date Observe the machine operation and record the minimum and maximum operating pressures. Since the Trim Saw uses a pressure compensating pump, the pressure should not vary significantly during operation. A sharp drop in pressure (more than 100 – 200 PSI) during a cycle is indicative of a flow problem. Items to check in this case include:








1) Place the heaviest load the machine will be expected to move.





200 PSI above the pressure recorded in step 3.

e

Listen to thevidence ofmuch fluid aplugged or erratic high pump may suction sideSquirt oil th

Suction Line

Volume Stop

Case Drain

e sound of the pump. A steady high pitched whi cavitation. Cavitation occurs when the pump is unabs it is attempting to deliver. This can occur if the suc

if the oil is too cold and the viscosity is too high. If thpitched whine that changes in pitch with changes in thebe aerating. Aeration occurs when outside air is intro of the pump. An air leak in the suction line is usua

e length of the suction line. An interruption in the aera

Relief Valv

ning sound is le to draw as

tion strainer is ere is a more machine, the

duced into the lly the cause. tion will locate

the air leak. When a pump is aerating, there is often a sound similar to marbles rattling inside the pump and foaming of the oil may also be present. OK Cavitating Aerating Check the pump case flow. Do this by measuring the temperature of the suction line and the case drain line with a temperature gun. Work the following formula to determine case flow:


PSI X .0093

Where “PSI” is the system operating pressure. The result will be the case flow of the pump in gallons per minute. A relatively new pump should bypass no more than about 1 – 3% of its total output. If the pump flow is reduced by as much as 10%, it should usually be replaced. Case Flow Check the temperature of the relief valve tank line. The tank line of the Trim Saw relief valve should never be hot. If it is, either it has become stuck open or it is improperly adjusted with respect to the pump compensator. The proper setting of the system relief is 250 PSI above that of the compensator. Relief Valve Tank Line Temperature Check the temperature of the inlet and the outlet lines of the cooler. If the cooler is functioning properly, the outlet line should be significantly cooler than the inlet. If there is only a small difference, either the cooler does not have good air flow or a portion of the cooler has become partially plugged. If the cooler becomes badly plugged, oil will bypass the cooler through the check valve. Feel the check valve or measure it with the temperature gun. It should stay cool at all times. If it is hot, oil is bypassing the cooler.

Temperature Drop Between Cooler Inlet and Cooler Outlet

ood Air Flow?

heck Valve Open (hot)?

Check the return line filter. This

ate Of Last Filter Change

heck the breather cap. The breather

reather Cap Clean?

ate Last Replaced

ecord the oil temperature. While it is normal for the oil temperature to increase

• System relief valve p (check the pump case drain)

f valve.

G C

filter should be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by the reading of the dirt indicator. The date of the last filter change should be recorded here and on the filter. D

Ccap on the Trim Saw is the spring type. It should be checked and cleaned at least monthly and replaced annually. If it is not replaced regularly, the spring can lose its tension and, though the cap itself may be clean, it will allow contaminants to enter the reservoir. Record the date when the breather was replaced here and on the breather. B D Rwhenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:

• Internally in the pum• The compensator may have been set above the relie

• Directional valve spools • Actuators

he source of the excess heat can be determined using the temperature gun.

il Temperature

heck the oil level (with any cylinders fully retracted). If the oil level is low, there

il Level

spect for leaks in the system and list below:

spect the hoses in the system. Are any of them rubbing on another hose, part

spect the pipe clamps. Proper hydraulic clamps should be used – conduit and

roper clamps?

roperly spaced (approximately every 5’ and within 6” of a termination)?

ist any other problems you have noticed that should be addressed:

TThis is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. O Cmust be a leak in the system. O In Inof the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. Inbeam clamps are unacceptable. P P L

Tyrone Berry Carriage Hydraulic Preventive Maintenance Schedule

Make several copies of this schedule and keep them handy for performing regular maintenance checks. Date The Tyrone Berry Carriage is a unique and efficient design. It is very reliable and can be expected to deliver many years of service if properly maintained. The two most common causes of failure in this system are heat and contamination. Heat problems in the Tyrone Berry Carriage are almost always the result of improper pressure settings. The system pressure will vary widely during operation of the carriage, but it should never exceed 1950 PSI. Monitor the pressure for a few minutes and record the highest pressure here. If the pressure exceeds 1950 PSI, even for a brief time, reset the pressures at the earliest possible opportunity. Max PSI At least quarterly, check and set all of the pressures in the system. Pump section No. 2 should unload whenever the system pressure exceeds 1400 PSI. Pump section No. 1 should unload whenever the system pressure exceeds 1800 PSI. Idle pressure in the system should therefore be 1800 PSI. Both unloading valves should be dumping pump flow back to tank, so the tank lines should both be warm. Record Idle Pressure Record Temperature Of Each Unloading Valve Watch the gauge as the carriage accelerates. When the flow path is opened, the large piston accumulator will discharge into the cylinder to provide flow. As the carriage picks up speed and the volume inside the accumulator is spent, the pressure will drop. When pressure drops to 1485 PSI, the No. 1 unloading valve should close.

Unloading Valve (#2 In Foreground)

Does No. 1 Close at 1485 PSI? There will likely be an initial pressure increase as the No. 1 pump flow is added to the system, then pressure should continue to drop as the carriage accelerates further. When system pressure drops below 1190 PSI, the No. 2 unloading valve will close. Does No. 2 Close At 1190 PSI? When the carriage stops, pressure will build again in the system as the accumulator fills. Watch the gauge climb. When the pressure reaches 1400 PSI, the No. 2 unloading valve should open. Does No. 2 Unload At 1400 PSI? When the pressure reaches 1800 PSI, the No. 1 unloading valve should open. Does No. 1 Unload At 1800 PSI? The pressures in the Tyrone Berry Carriage are critical for efficient operation. If they are off even 100 PSI, severe temperature increases can be noted, particularly when there is high ambient temperature.

Procedure for setting pressure:

1) Close the accumulator dump valve 2) Turn the main system relief valve counterclockwise 3) Turn unloading valve No. 2 counterclockwise to a ve4) Turn unloading valve No. 1 clockwise to a very high 5) Turn on the power, pull control lever to full open and

the bumper so that oil dumps across the main systeto 1950 PSI

6) Turn unloading valve No. 1 counterclockwise to a ve7) Turn unloading valve No. 2 clockwise until the gauge8) Turn unloading valve No. 1 clockwise until the gauge

Check the accumulator precharge. The recommended pPSI. There is a gauge at the top of the accumulator. Thisaccumulator precharge with the system shut down and tvalve open. The piston accumulator can become overchacan bypass around the piston and collect on top of it. If charging rig to the accumulator, open the bleeder valve anitrogen with the system under pressure. When the nitrogeexit the bleeder valve until the piston reaches the top of th

Main Relief

to a very low pressure ry low pressure pressure hold carriage against m relief. Set the relief

ry low pressure reads 1400 PSI reads 1800 PSI

recharge is 550 – 600 gauge will drop to the he accumulator dump rged as it is used. Oil this occurs, attach the nd bleed off all of the n is all bled off, oil will e accumulator. Once

all of the oil is forced out, shut down the power, open the accumulator dump valve and add nitrogen until the precharge is 550 – 600 PSI.

e

Accumulator Precharge Check the temperature of the inlet and the outlet lines of the cooler. If the cooler is functioning properly, the outlet line should be significantly cooler than the inlet. If there is only a small difference, either the cooler does not have good air flow or a portion of the cooler has become partially plugged. If the cooler becomes badly plugged, oil will bypass through the check valve. Feel the check valve. If it is hot, oil is bypassing the cooler and it may need to be flushed. Temperature Drop Between Cooler Inlet and Cooler Good Air Flow? Check Valve Cool?

Accumulator Dump Valv

Outlet

A strong indication of pump wear on the carriage is reduced current draw of the electric drive motor. Measure the current draw with an ammeter while the pumps are relatively new and track the condition of the pumps by checking monthly and recording here. Since the system pressure varies widely, be sure to check current draw while the system is at idle.

Current Draw
Check the filters. These filters should be checked and changed on a scheduled basis. The filter schedule should be determined by oil analysis, not by the reading of the dirt indicator. Change all filters at the same time. The date of the last filter change should be recorded here and on the filters. Under no circumstances should a filter be left in place more than 180 days. Date Of Last Filter Change Check the breather cap. The breather cap on the Tyrone Berry Carriage is the spring type. It should be checked and cleaned at least once a month and replaced annually. Failure to replace the breather cap regularly will result in weakening of the spring. If this occurs, even though the cap itself may be clean, contaminants may enter the reservoir. Record the date it was last replaced here and on the breather. Breather Cap Clean? Date Breather Last Replaced
Pilot Return Filter

REMEMBER THAT COMPONENTS DAMAGED BY CONTAMINATION WILL NOT BE COVERED UNDER THE TYRONE BERRY CARRIAGE WARRANTY! Record the oil temperature. While it is normal for the oil temperature to increase whenever ambient temperature does, excessively high oil temperature indicates bypassing in the system. Places where bypassing may be occurring can include:

• System relief valve or one of the unloading valves • Internally in one of the pumps • Valve spools • The large travel cylinder • The pilot circuit

The source of the excess heat can be determined using the temperature gun. This is best done shortly after startup before overheated oil can be circulated throughout the system. Under no circumstances should the oil temperature be allowed to exceed 140oF. Above this temperature, most hydraulic oils will begin to break down and leave varnish deposits. Oil Temperature Check the oil level (with any cylinders fully retracted). If the oil level is low, there must be a leak in the system. Oil Level Inspect for leaks in the system and list below. Inspect the hoses in the system. Are any of them rubbing on another hose, part of the machine or the structure? If so, list below. Check the length of the hoses. Unless required by the movement of the machine, hydraulic hoses should be no longer than about four feet. Hoses that are longer than four feet should be replaced by a length of hard pipe. Inspect the pipe clamps. Proper hydraulic clamps should be used – conduit and beam clamps are unacceptable. Proper clamps? Properly spaced (approximately every 5’ and within 6” of a termination)? List any other problems you have noticed that should be addressed:

Documents

Hydraulic Preventive Maintenance Schedule - … Door Hydraulic Preventive Maintenance Schedule Make several copies of this schedule and keep them handy for performing regular maintenance