CONTROL VALVES · 2017. 6. 13. · MANLTG01E rev.55 Page 2 Rev.5 May 2014 LTG1 – Control Valve Applicability This instruction manual is applicable for - LTG1 globe valves with standard

MANLTG01E rev.5

INSTRUCTION MANUAL

CONTROL VALVES

MANLTG01E rev.55 Page 2 Rev.5 May 2014

LTG1 – Control Valve

Applicability This instruction manual is applicable for

- LTG1 globe valves with standard contoured plug, soft contoured plug or BRD plug and threaded seat - LTG1-QC globe valves, with standard contoured plug or BRD plug and quick change design - LTG1-HP and LTG1-HP2S globe valve, with contoured plug and throttling cage, quick change design

and their LTA angle-style series.

REVISIONS:

REV. DATE PREPARED VERIFIED APPROVED 0 June 2007 PISTORE TEATINI MURONI 1 June 2010 CAROSELLI PISTORE MURONI 2 September 2010 CONTI CAROSELLI PISTORE 3 December 2010 CONTI PISTORE PISTORE 4 September 2013 PIATTI STRAMARE CONTI 5 May 2014 PIATTI STRAMARE CONTI 6 7 8 9



SAFEGUARDS

Instructions These instructions provide installation, operation and maintenance information for VALVITALIA LTG1. This document should be made available to personnel responsible for installation, operation, and maintenance of those valve series. Qualified staff only must be used to operate on the valve. The Company rejects any responsibility for personnel injuries and damages to equipment imputable to improper operation, use of non original spare parts or repairs executed by unauthorized staff.

Safety Messages Safety messages in there instruction and on label(s) on the valve are flanged with one of the words Caution , Warning or Danger . Those messages must be carefully read and followed to avoid personal injury and/or equipment damage. If a safety label becomes difficult to see or read, or if a label has been removed, please contact Valvitalia S.p.A. for label(s) replacement.

Inspection Valvitalia valves have been packaged to provide protection during shipment, however, it still can be damaged in transport. Carefully inspect the unit for damage upon arrival. If damage is detected, immediately file a damage claim with the carrier.

Storage Units should be stored in a clean, cool and dry location, and should be protected from dirt, chips, dust and other contaminants. For long term storage, the seating area should be protected from direct sunlight.

Replacement Parts Consult factory for recommended spare parts, read drawings and instructions for their correct use.

Noise In particular conditions the valve may generate high noise levels. In such cases it is therefore necessary to take the necessary precautions, according to the regulation in force.

WARNING! Personnel involved in the installation or maintenan ce of valves should be constantly alert to potential emission of process fluid and take appropriate safety precautions. Always wea r suitable protection when dealing with hazardous fluids. Hand le valves which have been removed from service taking into ac count the risk of entrapped hazardous fluid inside the valve.



Temperature In case that hot fluids flow through the valve, the operator must pay attention to not insulated parts. Hot surfaces may not be permitted in potentially explosive atmospheres. For more information refer to Annex A.

Lifting & Handling Lifting the valve improperly may damage it. Lift the valve with slings, chains or cables fastened around the valve body or fastened to bolts or rods through bolt holes in the flanges. Do not fasten lifting devices to the actuator assem bly!

Maintenance To service this valve you should have a full set of combination wrenches, flat tipped screwdrivers, Allen wrenches, a torque wrench, socket, chisels, a hooked tool for removing the packing and a dead blow hammer. If the valve is installed into a potentially explosive atmosphere, some rules concerning the maintenance operations must be taken into consideration. For more information refer to Annex A. Periodic lubrication is not necessary with the basic valve. See the actuator and accessory instructions for any lubrication requirements these assemblies may have.

Stuffing Box

DANGER! Packing must not be released or replaced when the v alve is under pressure.

Sealing Surfaces

Take care of body sealing surfaces which must not b e damaged during handling. Use wooden blocks or cloth strips to lay down the v alve during assembling/disassembling or general maintenance.

Removing Actuator

WARNING! DO NOT remove actuator from the valve assembly whil e pipeline is still under pressure. Depressurize pipeline befo re any operation on the valve assembly.



Table of Contents

LIMITATION OF USE ........................................................................................................................................................................................................... 6

GENERAL INSTALLATION TIPS .......................................................................................................................................................................................... 7

VALVE INSTALLATION ....................................................................................................................................................................................................... 8

VALVE REMOVAL .............................................................................................................................................................................................................. 12

VALVE DISASSEMBLY ......................................................................................................................................................................................................13

STEM AND PLUG REPLACEMENT ...................................................................................................................................................................................... 15

VALVE ASSEMBLY ............................................................................................................................................................................................................16

PACKING ADJUSTMENT ...................................................................................................................................................................................................16

PACKING REPLACEMENT .................................................................................................................................................................................................. 17

ATTACHMENT A ............................................................................................................................................................................................................... 18

ATTACHMENT B .............................................................................................................................................................................................................. 20



Limitation of use Residual Hazards according to Essential Safety Requirements ( Annex I ) Pressure Equipment Directive 97/23/CE 1 – MAXIMUM OPERATING PRESSURE AND TEMPERATURE Before placing the valve in pipe line make sure that maximum working pressure and temperature are within the limits of body rating and lower than allowable maximum values indicated on valve serial plate. 2 – MINIMUM OPERATING TEMPERATURE Remember that control valves made of carbon steel material (SA-105 or SA216 WCB) are suitable for a minimum fluid working temperature up to –29°C. 3 – PIPING STRESSES In general it is not necessary to perform any check and calculation if pipe size is no larger than 1,5 times valve body size (2 times for valve body size up to 3”). As the control valve has not to be used as a fixed point, if inlet and outlet pipe sizes are different, it should be considered the smaller one as it is essential for the piping design. 4 – VIBRATIONS When the control valve is correctly sized and selected important vibrations caused by the valve itself should not occur. However on severe services, small deviations from original process conditions may cause vibration phenomena of high intensity which can damage trim and actuator accessories (positioner, limit switches etc.). In this case it is necessary to restore the original service conditions or otherwise to change the trim type. 5 – SEISMIC STRESSES Valvitalia globe control are not significantly affected by seismic accelerations up to 0.5g. When control valves are equipped with large actuators and installed in a seismic region, it is necessary to perform appropriate calculations to check the yoke resistance. 6 – FLASHING AND CAVITATION When flashing or cavitation occur, it is advisable to use body materials such as CrMo alloy steels or stainless steel. Also body oversizing and increased rating are recommended. 7 – EXTERNAL FIRE Valvitalia control valves usually are not designed to withstand external fire. 8 – OVERPRESSURES

8.1 – Safety valves discharge Valvitalia control valves have to be protected against overpressures above the maximum allowable rated pressure. Short time pressure peaks are allowable during safety valve discharge, up to 10% over the maximum allowable working pressure. 8.2 – Water hammer Especially when incompressible fluids are handled, it is essential to not quickly close the valves to avoid hydraulic shock waves which cause uncontrolled overpressure and damages to piping and associated equipments 9 – ABRASIVE FLUIDS Abrasive solid particles carried by the fluid are the main cause of erosion and can cause a possible reduction of wall thickness of pressure containing parts. 10 – CORROSION For corrosion service Valvitalia LTG control valves are designed taking into account an allowance of body wall of 1mm for forged bodies and 2 mm for casted ones, up to a maximum wall thickness of 30 mm. In case of intergranular corrosion it is possible to predict the lifetime of valve , while for local corrosions such as pitting, interstitial corrosion and stress corrosion, is very difficult to get any realistic prediction of lifetime. In these case it is essential to properly select the material of valve body. 11 – LIFTING Lift valve with slings, chains or cables using eyebolts on valve body, fastened directly around the valve body or fastened to bolts or rods through bolt holes in the flanges. Failure to lift the valve properly may cause damage during handling and installation. 12 – DEAD-END PIPING DESIGN Valvitalia LTG1 control valves are not designed to perform dead-end piping closure under a pressure greater the max one specified in the technical book in the closed position. Consult engineering department for any information



General Installation Tips The LTG1 control valve can be easily installed in most piping systems. To ensure the valve is properly installed, make sure the following requirements are met.

SECTIONING AND BY-PASS VALVE

To allow for in-line inspection, maintenance and removal the valve without service shut-down it has to be provided a manual operated stop valve on each side of the control valve and a throttling valve, of the same port as the main control valve in the by-pass line

ORIENTATION Even if valves are normally installed in vertical posizion with upward oriented actuator, LTG1 series valves may be installed and properly operate in any position. However, vertical shaft orientation with downward actuator it’s not recommended due to solid particles hold by fluid which may head up in the packing

FLOW DIRECTION The flow direction is marked on the body or on the valve plate. The valve is unidirectional

PIPING LAYOUT To reduce the effect of downstream disturbance, a minimum straight pipe 6 DN long must be installed upstream the valve. Also a straight pipe 3 DN length (including reducers) must be installed downstream. Very low fluid velocities may allow upstream and downstream straight pipe lenght reduction. Reducers are allowed only if tapered and concentric. The observance of those requirements are necessary to the valve to operate properly according to the design pattern, with regard to sizing, noise generation, plug stability and so on.

VALVE TRAVEL The actuator is adjusted at the factory not to interfere with the proper closed and open position.

LUBRICATION Periodic lubrication normally is not necessary with the standard valve. See the actuator and accessory instructions for any lubrication requirements these assemblies may have.

. .



1. VALVE INSTALLATION

FOREWARD Before installing the LTG1 series valve, it’s necessary to verify that process operating pressure and temperature do not exceed the body rating.

1.1 Before installation remove all foreign material such as weld spatter, oil, grease and dirt from the valve, flanges and pipeline.

1.2 Follow piping layout and other installation tips (see pag.7 of this manual for

details).

1.3 Check piping connection distance, coaxiality and parallelism to avoid tensile and bending stresses which could occur when the valve is fastened to piping.

1.4 To lift the valve use appropriate eye bolts or other devices fitted on the valve. Don’t lift the valve keeping it from the actuator

1.5 In case of welding connections, it is recommended to avoid valve body

overheating. If the valve plug is provided by a plastic insert, it’s suggested to lift the plug over the seat during welding process. If excessive body heating is expected, the body temperature should be kept under control: the outside surface temperature should not exceed 100°C at 100 mm from the welding bead. In case of doubt, with plastic insert plugs, it is better to remove the trim from valve body before welding process.

1.6 Flange gasket is required. Tighten the bolts evenly, in a crisscross figure.

WARNING! Ensure that the valve, the pipeline and the mating connections are properly aligned before tightening the pipeline bol ts. Do not use the valve to force the pipeline into position.



Fig. 1 – LTG1 components location

Note: for both LTG1 and LTG1-QC, in case of BRD trim design, standard plug shall be replaced by a BRD plug, see fig.2

Fig. 2 – LTG1-BRD plug



Fig. 3 – LTG1-QC components location

Note: for both LTG1 and LTG1-QC, in case of soft trim design, standard plug shall be replaced by a soft plug, see fig.4

Fig. 4 – soft plug



Fig. 5 – LTG1-HP / LTG1-HP2S components location



2. VALVE REMOVAL FROM PIPELINE

To safely remove the valve from the pipeline carefully follow these steps. 2.1 Discontinue pipeline flow and relieve pipeline pressures in the portion of the flow

system where the valve is located.

2.2 Be careful to potential emission of pipeline material and take appropriate safety precautions. Always wear suitable protection when dealing with hazardous pipeline materials. Handle valves which have been removed from service taking into account the risk of entrapped hazardous fluid inside the valve.

2.3 Support the valve assembly, then remove the flange bolts or mechanical joint

connectors.

2.4 Carefully lift the valve from the pipeline as described in “Lifting & Handling” section (pag.3) and remove the valve from pipeline. Failure to lift the valve properly may cause damage during handling and installation.

2.5 Lay down the valve on wooden surface or cloth strips to prevent machined

surfaces from damages.

2.6 If the valve is installed in a potentially explosive atmosphere, the removal of the valve could involve a high risk. See section A.8 in Appendix A

WARNING! Pipeline pressure can propel the loose flange bolts and flanges, and can cause personal injury or equipment damage. Relieve pipeline pressure before removing flange bolts and flanges.



3. VALVE DISASSEMBLY – 3.1 LTG1

Fig. 6 – bellow

3.1.1 Remove the valve from the pipeline as described in the “Valve Removal From Pipeline” section. 3.1.2 Remove the actuator from the valve as described in the Actuator Instructions.

3.1.3 Remove all bonnet screws (4 – 5 ) with a suitable hex driver and remove bonnet assembly with stem and plug. If the valve is equipped with a bellow operation 3.3 is replaced by the followings (see fig.6): 3.1.3.1 - Remove all bonnet nuts and screws (A – B) with a suitable hex driver and remove the bonnet assembly. Remove the gasket interposed between the bonnet and the bellow’s flange. 3.1.3.2 - Remove all body nuts and screws (4 – 5) with a suitable hex driver and remove the bellow’s yoke. 3.1.3.3 - Unscrew the screw (C) and remove the plug, the stem (the bellow is integral with the stem) and the gasket interposed between the flange of the bellow and the yoke.

3.1.4 Before removing the packing assembly from the bonnet, please read “Packing Replacement” section.

3.1.5 Remove the gasket from the body. If problems occur and the seat ring is damaged, it must be replaced with VALVITALIA original spares. 3.1.6 Unscrew the seat (10) using the suitable wrench, as per fig. 7 and table 1

DN 25 DN 40 DN 50 DN 65 DN 80 DN 100 DN 150

Ø A 43 57 69 89.6 102 123 180

B 50 63 78 96 112 135 196

C 4.5 6 4.5 5 5 8 6

Ø D 4 4 4 4 5 5 5

E (Ch) 22 22 20 30 30 30 30

F 76 80 80 100 125 125 125

G 18 20 23 29 16 23 20

H 5 5 7 6 7 13 6

I 35 50 61 82 95 112 160 VALVITALIA

CODE 4ATR

015210H1 4ATR

015220H1 4ATR

015230H1 4ATR

015240H1 4ATR

015250H1 4ATR

015260H1 4ATR

015270H1

Tab. 1 – Seat Removal Wrench, dimensions



Fig. 7 – Seat Removal Wrench

3.2 LTG1-QC LTG1-HP / LTG1-HP2S

3.2.1 Remove the valve from the pipeline as described in the “Valve Removal From Pipeline” section. 3.2.2 Remove the actuator from the valve as described in the Actuator Instructions. 3.2.3 Remove all bonnet screws (4 – 5 ) with a suitable hex driver and remove bonnet assembly with stem and plug. If the valve is equipped with a bellow operation 3.3 is replaced by the followings (see fig.6): 3.2.3.1 - Remove all bonnet nuts and screws (A – B) with a suitable hex driver and remove the bonnet assembly. Remove the gasket interposed between the bonnet and the bellow’s flange. 3.2.3.2 - Remove all body nuts and screws (4 – 5) with a suitable hex driver and remove the bellow’s yoke. 3.2.3.3 - Unscrew the screw (C) and remove the plug, the stem (the bellow is integral with the stem) and the gasket interposed between the flange of the bellow and the yoke.

3.2.4 Before removing the packing assembly from the bonnet, please read “Packing Replacement” section.

3.2.5 Remove the gasket from the body. If problems occur and the seat ring is damaged, it must be replaced with VALVITALIA original spares. 3.2.6 On the upper surface of the cage there are some threaded holes: use these holes to keep out the cage from the body 3.2.7 Remove the seat by using the suitable threaded holes 3.2.8 Remove the seat gasket



4. STEM and PLUG REPLACEMENT There three different designs:

A. integral stem and plug for small ports, fig. 8 B. stem and plug two different pieces coupled with a screwed part and a pin, fig.9 C. stem and plug two different pieces coupled with a screwed part and a anti-

rotation device (screw (C)), fig.6

Fig. 8 – LTG1 Integral stem

Fig. 9 – LTG1 Screwed stem In case of design according to point A, it is necessary just to change the piece, in case of B and C design, the following instructions shall be followed

4.B.1 Remove the pin by pushing it out with a punch. 4.B.2 It is recommended to use an original new stem (not drilled). The plug may be

used again. 4.B.3 Screw the new stem into the plug paying attention to not damage machined

surfaces. 4.B.4 Drill the stem driving the tool in the existing hole in the plug. 4.B.5 Remove drill burrs. 4.B.6 Put some grease on a new pin and slip it into the hole. 4.B.7 Check stem and plug alignment on a lathe. If necessary straighten them with

a plastic rubber hammer

PAY ATTENTION: If soft seat is damaged (fig. 10) ask for the whole soft plug spare part. It is not recommended to change only the soft seat ring Fig. 10 – LTG1 Soft seat

Pin hole

Soft seat ring



5. VALVE ASSEMBLY 5.1 LTG1

5.1.1 Use original spares only 5.1.2 Carefully clean and grease the threaded surface of the seat 5.1.3 Screw seat into the body. 5.1.4 Slide plug and stem assembly into the guide already inserted in the bonnet 5.1.5 Place the body gasket in its seat 5.1.6 Screw studs in the body threaded holes then put the bonnet on the top of the valve body by fastening relevant nuts. 5.1.7 Follows packing replacement and actuator mounting instructions to complete valve assembly.

5.2 LTG1-QC LTG1-HP / LTG1-HP2S

5.2.1 Use original spares only 5.2.2 Carefully clean the seat surfaces of the static gaskets (6) (11) 5.2.3 Insert gasket and seat ring. 5.2.4 Insert seat into the body. 5.2.5 Insert the cage into the seat. Check the two pieces for alignment by rotating one on the other. Be sure that the gap between upper surface of the cage and sealing surface of the body is included between 0,3 and 0,7 mm 5.2.6 Slide plug and stem assembly into the cage till plug and seat surfaces touch each other 5.2.7 Screw studs in the body threaded holes then put the bonnet on the top of the valve body by fastening relevant nuts. 5.2.8 Follows packing replacement and actuator mounting instructions to complete valve assembly.

6. PACKING ADJUSTMENT

6.1 If leakage through the packing occurs, tighten the packing nuts just enough to stop the leakage.

Over-tightening will cause excessive operating force, high friction and premature packing wear.

6.2 If packing leakage cannot be stopped by tightnening the packing nuts, the

packing must be replaced. Read the relevant section on this manual to replace packing.



7. PACKING REPLACEMENT

7.1 Close the valve and relieve pipeline pressure.

7.2 If the actuator is powered, disconnect and lock out the pneumatic, hydraulic, or electrical power to prevent accidental operation of the actuator.

7.3 Remove the actuator from the valve following related instructions. 7.4 Remove the actuator adaptor from the top of the valve. 7.5 Take out screws that hold the packing gland and slide gland off the valve shaft. 7.6 Packing replacement :

7.6.1 Remove all the old packing rings from packing chamber with a hooked tool. 7.6.2 Apply a light film of grease to the inside and outside diameters of the new

packing, then install the packing one right at a time. 7.6.3 Push the packing firmly in place (don’t use sharp or pointed tools).

7.7 Slide the packing gland (7) down the shaft until it just contacts the packing. 7.8 Screw the packing gland screws into the body. 7.9 Fasten the actuator mounting bracket to the top of the valve. 7.10 Install the actuator on the valve following related instructions. 7.11 If the actuator is powered, reconnect the pneumatic, hydraulic or electrical power. 7.12 After the valve is pressurized, check for packing leaks. 7.13 If packing leaks, tighten the packing gland screws just until the leak stops. 7.14 Caution: Do not overtighten packing nuts .

WARNING! Removing packing while the pipeline is under pressu re can cause personal injury or equipment damage. Relieve pipeli ne pressure before removing the valve packing.



ATTACHMENT A. INSTRUCTIONS REGARDING THE EMPLOYMENT IN POTENTIALLY EXPLOSIVE ATMOSPHERES

A.1 Marking The valve shall be marked as shown in fig.11, in compliance with Directive 94/9/EC on equipment and protective systems intended for use in potentially explosive atmospheres. Here below the explanation of the marking:

Fig. 11 –CE marking according to 94/9/CE

TX – see the following instructions IIC – explosion group c – protection type. c = constructional safety protection type GD – ignition source. In this case only gas (symbol “G”) shall be consider as hypothetical ignition source. 2 – safety level. Safety level 2 includes the equipment designed and constructed to prevent ignition sources even in the event of frequently occurring disturbances or faults, which have to be taken into account. II – group of equipment. Group of equipment II applies to equipment not intended for use in underground parts of mines, and to those parts of surface installations of such mines Ex – specific marking of explosion protection

If the control valve is actuated by a pneumatic diaphragm actuator PDA type, CE marking will be unique because the valve and actuator must be considered an assembly composed of a combination of these two devices keep together to form a single functional unit. If the valve is assembled with another kind of actuator, the actuator must be already in compliance with the Directive 94/9/EC. In this last case the above CE marking will be related to the control valve only.

A.2 Principles During the normal working and the expected malfunctions of the equipment no potential ignition source must be consider if the below rules will be applied: A.2.1 – the equipment work in his working range (defined on product data sheet) A.2.2 – Use of ATEX certified accessories suitable for the employment zone A.2.3 – the application of all the measures that this Maintenance and Use Manual describes and foresees A.2.4 – Do not modify the equipment; for any problem contact Valvitalia Technical Office

ATTENTION! These instructions are integral part of this Mainte nance and Use Manual. The violation of the instructions of this c hapter can involve serious injury or damage to people or thing s.



A.3 Consequence of foreign body inlet or impact Building materials are suitable to withstand to a foreign body impact of 40J without any predictable ignition. Final user have to check that this above mentioned value is not overtaken. Foreign bodies inlet into spring’s chamber does not involve any risk, since they cannot be consider as ignition sources.

A.4 Temperature class The surface temperature of valve body depends on process fluid temperature. Make sure that the maximum temperature of the fluid does not exceed the maximum allowed temperature in the area of employment. The equipment has been designed take into consideration the design pressure indicated on the valve datasheet and it is designed to work at the relevant operating pressures. Avoid the occurrence of adiabatic compression and protect the upstream and downstream line from any shock wave. exothermic reactions between fluids must be avoid. For all these reasons, the marking necessary for compliance with UNI EN 13463-1 shall include the symbol TX. Employment in presence of gas: the maximum surface temperature is defined in UNI EN 13463-1 and listed in the below table: ATTENTION: Solar radiation or thermal radiation generated by any hot body could increase the surface temperature of the actuator. Dust accumulation can increase this temperature too (insulating behavior). Dust deposits greater than 5mm must be removed.

Temperature class Max surface temp. [°C] T1 450 T2 300 T3 200 T4 135 T5 100 T6 85

Tab.2 – Max surface temp.

A.5 Electrical conductivity

The equipment is designed so that the electrical conductivity is guaranteed. The end user must guarantee the electrical continuity between the valve and the piping and the appropriate connections to ground as by law enabled. In case of protective coatings of electrical equipment, they should be consistent with EN13463-1 and TR50404. The risk of ignition by electrostatic charges is minimized by using of conductive materials, connected in equipotential way, and the absence of non-conductive coatings. Any coatings should comply with the requirements of EN 13463-1 and TR 50404 for explosion group IIC.

A.6 Installation The end user must guarantee the absence of explosive atmosphere during the installation of the equipment. This is especially important when welding operations are required, since: - flames or electric arcs are not allowed - welding operations would exceed the minimum ignition temperature of most gases and vapors normally used in the plant.

A.7 Maintenance Maintenance should be carried out by highly trained technician and in compliance with this Maintenance and Use Manual. Maintenance tool should comply to UNI EN 1127-1, Appendix A. Zone 1: only steel tools that could cause single sparks produced by impact or friction are admitted (screwdriver , monkey wrench, ecc.). Tools which produce continuous sparks (for example, grinder) are allowed if it’s possible guarantee the absence of explosive atmosphere during the maintenance operations. It is strictly forbidden the use of any steel tool in zone 1 if there is an explosion risk due to chemical substances of group IIC (acetylene, carbon disulfide, hydrogen). Moreover it is strictly forbidden the use of any steel tool in zone 1 if there is an explosion risk due to the following chemical substances: hydrogen sulfide, ethylene oxide, carbon monoxide. Use of work tools in zone 1 and 21 shall be subject to a “work authorization”. Always use a safety-approved clothing, suitable for potentially explosive atmospheres.



In presence of gas, vapor or gas and vapors leaks, it is useful to use portable gas detector.

A.8 Disassembling The end user must guarantee the absence of explosive atmosphere during the disassembling of the equipment. This is especially important if cutting operations involving flames or sparks are involved. For example grinding sparks are able to ignite an explosive atmosphere.

ATTACHMENT B. ADDITIONAL SAFETY REQUIREMENTS RELATED TO MACHINERY DIRECTIVE 2006/42/EC

B.1 Machinery Valve is a machinery, according to what stated in article 2(a) of Machinery Directive 2006/42/EC:

An assembly, fitted with or intended to be fitted with a drive system other than directly applied human or animal effort, consisting of linked parts or components, at least one of which moves, and which are joined together for a specific application. Or an assembly referred to in the [above] indents, ready to be installed and able to function as it stands only if mounted on a means of transport, or installed in a building or a structure, For this reason, valve could became a source of risks. These can be kept under control by following the safety requirements contained in the previous sections of this Instruction Manual and the followings. Valve maintenance is not intended for use by consumers. Only trained personnel is allowed to work on valve, actuator and its accessories

B.2 Assembly Machinery must be intended as valve, actuator and all its accessory in the fully assembled design. However VLT valves intended to be fitted with a drive system but supplied without it may also be considered as machinery. In this case the technical documentation approved during the order must be taken into account for assembly purposes. - Stem MAST - valve torques or thrusts - top mounting design, and all others technical characteristic shall be communicated to customer. The same shall be applied to parts disassembled for storage or transport purposes, i.e. blow out / blow through kits.

B.3 Moving parts Must be paid attention to rising stem. Valve and actuator stem shall be accessible for maintenance purposes. Accessibility shall be guarantee in order to perform all the needed linkages too (positioner, box switch shall be connected to valve’s stem in order to close the control loop). The movement of the stem could became a source of risk. Special care has been paid in the analysis of overall dimensions, so to prevent the risk of crushing, but residual hazards such as entanglement could happen. In most cases, velocity of rising stem is limited to 2 ÷ 10 mm/sec. but special application require faster responses.

ATTENTION! These instructions are integral part of this Mainte nance and Use Manual. The violation of the instructions of this c hapter can involve serious injury or damage to people or thing s.



Maintenance on valve stem, actuator stem and stem connector shall be performed only when the stem is not moving. Personnel on the plant has to be properly trained about the design of the pneumatic scheme installed on the valve

B.4 Blockage Even if a blockage does not itself create a dangerous situation, the occurrence of blockages often requires operators to intervene quickly in order to avoid damage and loss of production, thereby increasing the likelihood of dangerous intervention. In case of undesired blockage: - if the blockage is due to a limit stop not properly settled or actuator’s handwheel not in its neutral position - it is enough to set again these equipment - if the blockage is due to a mechanical problem occurred (i.e.: stem break-up, stem deformation, seizure between plug and cage), no further action can be done to solve the problem. Valve disassembly is needed in this case. Valve’s damage able to create irremediable effects are mainly two - Blockage of plug due to seizure between the plug itself and the cage (guide) - Blockage of plug due to stem damage

If one of the above facts happen, the valve will not be able to control or reach its safe position. In order to avoid seizure: - Blowing of the line must be done during the start up of the plant, dirty or solid particles able to create seizure between plug and cage (guide) must be avoided

In order to avoid stem damage: - Do not change actuator preload - Do not exit the range of air set setting

B.5 Reasonably foreseeable misuse

A reasonably foreseeable misuse could occur all those time when a setting is changed. Here below the main points to be focused - air set setting: a supply pressure greater than the maximum allowable could damage the diaphragm or valve’s stem or the stem of the actuator; a supply pressure lower than the minimum allowable don’t allow the control Minimum and maximum allowable air supply are clearly stated in valve datasheet. - actuator preload: factory actuator preload must not be changed - positioner setting: during FAT positioner is calibrated. Any changes to initial setting must be done by trained personnel.

B.6 Risk of explosion The risk of explosion posed by or within the machinery itself or by gases, liquids, vapours or other substances produced or used by the machinery are covered by the MD. Valve is designed in order to limit this risk, in accordance to customer requirements and precepts of applicable project specifications. Personnel shall be aware of process fluids and residual risks related to explosion.

B.7 Leakage of hazardous fluids Valve is designed in order to limit this risk, in accordance to customer requirements and precepts of applicable project specifications. Leakage from body gasket should not happen. In case of leakage an inspection shall be performed Leakage from packing should not happen too. In case of leakage an inspection shall be performed, packing can be tightened or replaced as per instructions of sect.6 and 7

B.8 Maintenance Must be taken into account that valve’s components aren’t subjected to specific wear that can lead to valve’s break VLT recommendation is to visual check the valve once a year. Only soft parts shall be replaced every time that the valve is disassembled Reference is made to specific IOM for each accessory



B.9 Electricity and static electricity The electric conductivity in the valve is guarantee by a proper design. All the accessories have been designed with ground connections. These must always be properly connected.

B.10 Handling and lifting

Valve shall be handled and lifted as per Fig.12

Fig. 12

B.11 Stability Valve is generally equipped with a pedestal. This pedestal doesn’t guarantee anyway the stability of the valve. Do not leave the valve (neither in the bare stem configuration nor in the fully equipped configuration) upright, supported by the pedestal. It must be used for machining purposes only. Valve must be always supported by chains or ropes as per fig.12.

B.12 Operating conditions Valve is generally equipped with a pedestal. This pedestal doesn’t guarantee anyway the stability of the valve. Do not leave the valve (neither in the bare stem configuration nor in the fully equipped configuration) upright, supported by the pedestal. It must be used for machining purposes only. Valve must be always supported by chains or ropes as per fig.12.

B.13 Noise Valve’s trim is designed in order to limit the noise level, if this should exceed the maximum allowable level. In case of operating conditions not reasonably foreseeable or different from those communicated, noise level could exceed the above limits. Use of noise insulation equipment can be taken into account.

B.14 Radiation Valve is not influenced by external radiation. The valve does not emit radiations. Electric accessories must be in compliance with all the required standard for electromagnetic compatibility

Documents

CONTROL VALVES · 2017. 6. 13. · MANLTG01E rev.55 Page 2 Rev.5 May 2014 LTG1 – Control Valve Applicability This instruction manual is applicable for - LTG1 globe valves with standard