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Centrifugal Fans maintenance manual

www.dcs.fi

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Contents 1 Safety ............................................................................................................................................ 4

1.1 Explanations .......................................................................................................................... 4

1.2 Basic safety rules ................................................................................................................... 4

1.3 Noise level ............................................................................................................................. 5

2 General .......................................................................................................................................... 6

2.1 Fan types................................................................................................................................ 6

2.1.1 Use types ........................................................................................................................ 6

2.1.2 Wing types ..................................................................................................................... 7

2.2 Accessories ............................................................................................................................ 7

2.2.1 Sensors ........................................................................................................................... 8

2.3 The marking of the fan .......................................................................................................... 8

2.4 Installation ............................................................................................................................. 9

2.4.1 Dimensions, weight and lifting instructions .................................................................. 9

2.4.2 The beam frame ............................................................................................................. 9

2.4.3 Concrete base ............................................................................................................... 10

2.5 Operating conditions ........................................................................................................... 10

2.6 Storage ................................................................................................................................. 10

3 The introduction of the fan ......................................................................................................... 11

3.1 Introduction ......................................................................................................................... 11

3.2 Start-up ................................................................................................................................ 11

3.3 Monitoring during the operation ......................................................................................... 11

3.3.1 Vibration ...................................................................................................................... 11

3.3.2 Noise ............................................................................................................................ 12

3.3.3 Bearing sound .............................................................................................................. 13

3.3.4 Vibration dampers ........................................................................................................ 13

3.3.5 Drive belt...................................................................................................................... 13

3.3.6 Flexible connectors ...................................................................................................... 13

3.3.7 Hub seal........................................................................................................................ 13

4 Maintenance ................................................................................................................................ 13

4.1 Impeller ............................................................................................................................... 14

4.1.1 General ......................................................................................................................... 14

4.1.2 Impeller installation ..................................................................................................... 14

4.1.3 Removing the impeller ................................................................................................. 18

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4.2 Bearings ............................................................................................................................... 19

4.2.1 General ......................................................................................................................... 19

4.2.2 Lubrication ................................................................................................................... 20

4.2.3 Lubrication intervals and amount of grease ................................................................. 22

4.3 Electric motors .................................................................................................................... 22

4.4 Electrical connections.......................................................................................................... 23

4.5 Hub seal ............................................................................................................................... 23

4.6 Switch .................................................................................................................................. 23

4.7 V-belts ................................................................................................................................. 23

5 Troubleshooting .......................................................................................................................... 24

6 Maintenance intervals ................................................................................................................. 25

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1 Safety

1.1 Explanations

The manual contains warnings. They indicate hazards that can cause

injury and the likelihood of their occurrence. The warnings are divided

according to the severity: DANGER! Warning! and Important!

DANGER! Means the accident, which in case of non-compliance with

the instructions will result in serious injury

Warning! Means that an accident may occur, resulting in serious

personal injury if the instructions are not followed

Important! Means that an accident may occur, which results in personal

injury or property damage

Note! Means operational interference or damage due to improper use

1.2 Basic safety rules

The use of the machine correctly and in the right circumstances

guarantees the safe operation of the fan. The fan should be used only for

the purposes for which it is made and the user must follow the general

safety precautions. The fan should also be installed in accordance with

the instructions. The fan is manufactured in compliance with safety

standards, marked with the CE mark and is supplied with a declaration

of conformity.

Improper use may result in accidents and/or cause damage to the device.

o the fan may only be used in its intended conditions

o safety devices of the fan must not be removed under any

circumstances and do not reach behind the protective covers

o precaution of moving parts

o the fan may only be maintained by the professional specialized to

provide service

o the fan must not be used for moving another kind of air or gas

than what it is made to move

o after maintenance, always check the structures and all the

protective covers

o the user must have the appropriate protective equipment

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o after service all bolts and nuts should be checked, as well as their

tension

o Do not exceed the maximum speed specified for the fan

1.3 Noise level

EU Machinery Directive 89/392/EEC requires a one-meter distance from

the measured sound pressure and sound power level. Maximum sound

pressure is measured at the front of the suction side.

The sound power level is defined as the measurement methods BS 848

and VDI 2081.

Sound pressure and power levels are indicated on the base of the fan

case.

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2 General This document contains the most common maintenance procedures of

the product, instructions for proper use and safety instructions. These

instructions are designed to ensure an efficient, correct and safe

operation of the fan. Proper maintenance and operation extend the life

cycle of the fan.

NOTE! Maintenance and repair staff must be qualified. Following these

maintenance manuals requires good basic skills at maintenance and

experience in similar maintenance tasks. Maintenance and repairs must

be done by this manual, as well as instructions that supplier of parts and

components offers. Also applicable safety regulations must be followed.

Service documentation must be kept with the product, or in its vicinity,

so that it will be easy to find.

2.1 Fan types

The fans are classified according to the operating and the impeller type

as well as the rotation and air flow direction of the fan.

2.1.1 Use types

The impeller is mounted on the motor shaft (use Type-S), which is

sometimes also called a direct-driven fan.

In the belt driven fan (the use of type-H), engine power is transmitted to

the impeller shaft using a V-belt. The motor is attached by the

adjustment rails to the stand.

In a switch operated fan, (use type-K) the power transmission is

performed by the switch connecting the motor and impeller shafts and

with the impeller shaft with separate bearings.

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Rotational and blow directions

When determining the blowing direction, the fan is considered from its

operating side. The direction is shown in accordance with the drawings

with letters indicating the direction of rotation (RD impeller rotates

clockwise or LG impeller rotates counter-clockwise) and with numbers

that indicate the angle between the air flow direction and the vertical

direction in degrees.

If the main directions indicated in the figure cannot be used, the fan may

be produced to set any intermediate direction.

2.1.2 Wing types

The direction and the shape of the impeller blades influence the different

characteristics of the fan. These characteristics are the yield of pressure

and volume, the efficiency and the volume flow rate. The choice of the

wing type also affects the particles moving with the gas entrained.

2.2 Accessories

The instructions and documents of the accessories such as sensors,

dampers, guide vane controls, vacuum boxes and engine accessories are

submitted on a case by case basis.

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2.2.1 Sensors

The validity of the fan warranty requires the connection of the condition

monitoring sensors supplied as the accessories of the fan and

introduction of surveillance.

The "standard" surveillance packet offered for fans as an option,

contains at least one rotation monitor, one vibration monitor, two

temperature sensors + converters and four 5 m extension cables. Upon

the request of the customer, condition monitoring may be larger.

Condition monitoring sensors as standard equipment are for the fans

with oil lubricated bearings or the engine power of 250 kW and

upwards.

Oil lubricated bearings are always equipped at least in the impeller end

bearing with vibration measurement and both bearings with temperature

measurement (oil lubrication sensor packet includes VKV021, two

TS229, two TP3237 and three EVC005).

Fans equipped with motors of 250 kW and above include as standard

accessories in addition to bearings monitoring (vibration and

temperature monitoring in both bearings), also vibration and temperature

monitor on D-end of the motor.

Temperature sensor TS2229

Measurement signal converter TP3237

Vibration guard VKV021

Plug connector/cable 5m EVC005

Rotation monitor

The speed monitor is DI6001 [M18] (if necessary, the DI5003 [M30]

can also be used).

In case of separate bearings (vertical bearing housings) the sensor is

most commonly mounted between the bearings and the output gauge is

attached to the shaft with a compression fitting. The sensor bracket is

bolted to the base and the sensor is mounted so that the clearance

between the output gauge is 6 mm (DI5003 5 mm).

2.3 The marking of the fan

In each fan is a shield, which is marked with the required information

about the fan. The fan has an alphanumeric code that indicates the type

of fan. The shield also indicates the year of manufacture, the serial

number and the fan performance values. The shield also bears the CE

marking.

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For example, DCKE-40/2-j-k RD90

DC Affix which is not relevant (Dust Control)

KE K = marking of the series on the fan (M, D, E, H, B, C or D)

, E =wing type (E, T, S or L)

-40 Nominal size of the fan

/ 2 Narrowing, if you have a narrowed impeller (/2 or /3)

-j Included, if the fan has a cooling disc

-k Type of use (-k = switch,-s = impeller on the shaft of

The motor, -h = belt (not marked in the name))

RD Rotation direction (RD or LG)

90 Blow direction (0-359 °, 0 is up)

W In belt drive motor position (W or Z)

2.4 Installation

2.4.1 Dimensions, weight and lifting instructions

Fan-specific assembly drawing includes dimensions, weight data and

lifting instructions. Permitted lifting points are marked on the fan.

2.4.2 The beam frame

The centrifugal fans are mounted horizontally on vibration dampers.

Dampers should be installed only when the fan is at the level of the

installation, in order to prevent damage to the dampers in the context of

the drop, the Dampers should be able to flex freely. The sag is

determined according to the damper type, for example, LV 10/200 will

sag under load 7.5 - 9 mm (75 - 90% of 10 mm), and deflection should

be the same + / - 1 mm between all the dampers.

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2.4.3 Concrete base

If the fan is mounted on a concrete base, it needs case bushings and a

levelling partition if the base is not smooth enough. When the

installation is clear, the concrete mixture is cast under the mounting

flange. When the concrete mixture has dried, the bolts are tightened.

2.5 Operating conditions

Operating conditions of a fan are largely determined by the choice of

manufacturing material, surface treatment, outfitting and structure of the

fan. As a result, the fan may only be used for the specified

application/conditions. The fan is to be placed in a warm and dry

internal space (5 ... 40 ° C), which is free from condensing, unless

otherwise agreed with the fan manufacturer.

Corrosives, high temperature, solids and external constraints such as air

humidity can weaken the parts of the fan. If the operating conditions are

different from normal, the fan has to be originally designed for use in

these abnormal circumstances.

2.6 Storage

Fan and motor must be protected from moisture and dust. Large

temperature changes should be avoided. Otherwise, damage can occur to

the electric motors, plastic fittings and bearings, painted surfaces or

seals. All materials are not weather resistant. Suction and discharge

openings must be closed during storage.

Prolonged standstill may affect the lubrication properties of grease or

oil. Corrosion may also affect the bearings. Certain components, such as

bearing seals and V-belts in belt-driven fans can become brittle over

time. The fan should be used at least about 10 min monthly. If this is not

possible, it is recommended to rotate the impeller by hand. This

maintains the operational condition of the bearings.

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3 The introduction of the fan

3.1 Introduction

1. Check the fan and motor mounts to the frame, anti-vibration

mounting to the base, the suction and discharge opening connections

to the duct and check the tightness of the bolts.

2. Check the belt guard or the connection guard mounting and

clearance (at least 10 mm) in relation to the moving parts.

3. Check that the direction of rotation of the fan (motor) and the

direction of the gas flows are in the direction of the arrows on the

casing by switching on the fan for a while.

4. Check the fan bearings. If there is reason to suspect that

condensation of water has entered the bearings e.g., during storage,

the bearing is to be opened, cleaned and re-greased.

5. Check all guards and protective covers.

6. Check that there is nothing inside the fan.

3.2 Start-up

When starting cold a fan which carries hot gas, its power consumption is

considerably greater than the operating conditions. If power

consumption is determined in accordance with the operating conditions,

the fan is to be started against the closed damper or regulator. The

damper or regulator is gradually opened to the run position along with

the increase of the gas temperature.

In order to avoid the switch and motor load and overheating it is

recommended up to four starting times per hour, unless otherwise

specified in the documentation. Between start-up times should be at least

ten minutes of cooling time. Excess vibration or noise are the signs of a

faulty operation, in which case the operation of the fan is not allowed to

continue until the fault is cleared and repaired.

3.3 Monitoring during the operation

3.3.1 Vibration

Vibration is a significant factor in terms of performance and life-cycle of

the fan, which is why vibration control is very important. Vibration can

cause cracks, bearing failures, bolts loosening and noise. Periodic

vibration measuring is recommended. Vibration is a great gauge of

condition monitoring. The machine's operations can extensively be

interpreted on its basis. For critical needs, tough conditions or larger

than 50kW fans we recommend continuous vibration monitoring

equipment.

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Vibration can be caused by wear of the impeller, dirt accumulated in the

impeller, contact of moving parts with other parts or an imbalance

caused by the alignment of the fan. Good tools for vibration

measurement are, for instance, the SPM Leonova Infinity or SPM

Bearing Checker.

Dust Control Systems Oy manufactured impellers are balanced

dynamically according to ISO 1940 class Q 6.3.

In operating conditions the fan vibration stress value must stay below the

value of alarm limit. Once the value of alarm limit is exceeded, the

impeller cleaning and bearing checking must be carried out as quickly as

possible. If these measures do not help, the impeller must be re-balanced

or other vibration removing repair must be performed.

It is advisable to discontinue the use of the fan and to contact the

manufacturer of the fan if, on use, the vibration stress values exceeds the

value of trigger limit. If the reason for vibration is not recognized with

certainty and are determined to be harmful, the fan cannot be used when

the trigger limit is exceeded.

Measurements are performed according to ISO 10816 standard, within

the fan operation rotation frequency.

The following table applies to fans that are equipped with vibration

dampers (flexible platform). Specific instructions are presented in

separate annex Sensor limits, or in separately defined fan-specific

instructions.

Assessment of fan vibration stress values (v r ms ) according to standard ISO 10816.

Coupling

operated/

Impeller mounted

on the motor

shaft

Belt operated

Trigger limit 7,10 11,2

Alarm limit 4,5 7,1

3.3.2 Noise

The fan causes noise while operating. Noise levels and the frequency

depend largely on the size and structure of the fan. The noise does not

always reflect a defect in itself. If excessive fan noise becomes apparent

during operation or some extra sound occurs, it may be a sign of a

malfunction. In certain circumstances, the clearance between bearings

may cause a rattling sound if the bearing temperature rises.

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Bearing operating temperature is affected by the speed and

environmental conditions. The maximum permissible operating

temperature depends on the bearing structure, the used lubricant and the

length of lubrication intervals.

Normally, the greased bearing temperature must not exceed 65°C,

measured from bearings housing, and never 110°C, measured from

bearing.

The rise of temperature may be due to a faulty bearing, lack of

lubrication, or too generous amount of lubricant.

3.3.3 Bearing sound

The bearings sound can be heard and measured with devices separately

manufactured for this purpose. Vibration level measurement and

measurement with bearings test devices are the right way to distinguish

between the sound caused by the failure of the structure.

3.3.4 Vibration dampers

Check that the dampers are in good, working order and evenly loaded. In

addition, the dampers must be able to flex freely.

3.3.5 Drive belt

Check the amount and tension of belts. Typically, stretched and worn

belts vibrate and make a noise.

3.3.6 Flexible connectors

Installation instructions and tolerances for the connectors are in the

annex.

3.3.7 Hub seal

The fan may be provided with a hub seal used for sealing of the impeller

hub and the fan casing bushing/joint. If discharged gas leaks from the

joint inside the fan, it is advisable to check the sealing operation.

4 Maintenance Service date and the length of the maintenance periods are determined

by the maintenance and repair needs. Sufficient spare parts must be

available. The attached table of the most common service and

maintenance work periods.

NOTE! One must keep maintenance dairy that shows performer of the

maintenance, date and what substances and parts have been used. Used

substances and parts must be specified by manufacturer.

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4.1 Impeller

4.1.1 General

If the fan operates with exhaust gas or in dust containing air, or if in the

impeller has been formed a deposit or unusual wear, it may cause a

balance disorder. This can result in damage to the bearing or impeller

failure.

Impeller cleaning is carried out with a wire brush or scraper. The loose

dirt should be removed from the fan housing before the fan is restarted.

For inspection and cleaning of the impeller, in the fan casing is usually

an inspection hatch.

A worn impeller must be replaced or repaired by welding. After

welding, the repair of the impeller is to be balanced again.

Measure the vibration level from the frame of the motor and from each

of the bearing housing, from three different directions.

4.1.2 Impeller installation

Follow the instructions concerning the coupling and belt operated fans.

If the fan has a V-grooved hub, its fitting is carried out by tightening

against the shaft shoulder and preventing opening of the screws of the

locking plate, for example, by welding the screw into the locking plate.

1. Remove cover and clean the impeller and shaft contact surfaces

thoroughly. Detailed instructions are in the Annex labelled

installing the clamping sleeve (EX- and SKF SHT- sleeve).

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2. Set the friction joint sleeve in place so that the bolt positions do

not exceed the front edge of the hub.

3. Place the impeller into the shaft. Make sure that the friction joint

sleeve is still in place in the depth direction. It is recommended

to install impeller with fan-specific impeller lift tool (available as

accessory, with additional assembly drawing in fan-specific

documentation).

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4. Fit the inlet cone and check whether it fits into the place. Tighten

the bolts of the friction joint sleeve according to the tightening

instructions. The friction joint sleeve tightening instructions are

attached.

To achieve the right connection, tightening is to be carried out on all the

bolts several times by gradually tightening each bolt in turn, until

tightening the last bolt no longer loosens the first tightened bolt and the

torque prescribed by instructions has been reached.

5. On the inner surface of the outer rim of the front panel of the fan

are adjustment screws for the inlet cone position.

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6. Attach the inlet cone bolts and tighten them to the desired torque.

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7. Place heat-resistant silicone (e.g., Super RTV silicone, red 60 ...

315 ° C) between the surfaces of the impeller hub plate and the

impeller hub and attach the hub plate evenly by tightening the

torque.

4.1.3 Removing the impeller

EX-41

Remove the screws and screw them into the pull-out threads of the outer

ring so that the inner ring is released and the sleeve comes off. Remove

the screws from the pull-out threads only when the sleeve is removed

from the hub.

EX-60

Method 1: Remove the screws and screw them into the outer ring pull-

out threads and release the ring.

Method 2: Remove the screws to the pull-out threads of the central

flange and release the rear inner ring

SKF SHT

Detachment instructions in separate annex.

V-grooved hub

Remove the locking plate and pull the impeller off with a wheel puller.

Sometimes, the impeller is so rugged that the damage of the shaft cannot

be avoided. A damaged shaft must be replaced.

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4.2 Bearings

4.2.1 General

The bearing types used in the fans produced by Dust Control Systems

Oy are generally spherical ball or roller bearings and toroid bearings.

They are attached to the shaft with a clamping sleeve. There are two

bearings, one of which receives the compression load. This bearing

locked to the axial direction must be marked when both bearings are

replaced at the same time.

In the fans are used mainly two vertical bearing housings (separate

bearings), which are SKF manufactured SNL or SONL-bearing housings

or ConCentra bearing units. SNL and ConCentra bearing housings are

lubricated with grease and SONL bearing housings are lubricated with

oil.

ConCentra units are designed to facilitate installation and maintenance.

ConCentra bearing units are assembled, greased and pre-sealed.

ConCentra advantages include easy installation, longer service life,

greater reliability and easy maintenance. In DCS fans are used

ConCentra SYNT bearing units. ConCentra bearing units are used in

small and medium-sized fans.

DCS fan bearings are always determined in fan case bases taking into

condition the design input data and the fan operating conditions to

achieve optimal serviceability and reliability.

The bearings must be handled with care and must be protected from dust

and moisture. The bearings are therefore kept in the original packaging,

which should be opened only upon installation. The rust-preventive

agent in the new bearings does not need to be removed, if the bearing

has not been contaminated. For cleaning of bearings use a white spirit or

a similar detergent. After washing, the bearings are lubricated with oil

immediately.

The shaft pins, bearing housings, etc., must be thoroughly cleaned and

soaked in oil prior to installation. Taper bushing surfaces must be only

lightly lubricated. Achieving a suitable interference fit may otherwise be

impaired.

After installation, oil must also be entered into the bearings, in order to

avoid dry running at start-up. After lubrication and the installation of the

bearings, a test run is carried out, during which is monitored the

temperature rise and operating noise of the bearings.

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The condition of the bearings is recommended to be monitored by

measuring devices and methods of condition monitoring. It should be

noticed when analysing measured values that the bearing condition and

load of the bearing are different due to the requirements set by the

structures.

NOTE! Bearing loads are very low and the load direction can vary

depending on the operating situation. The interpretation of measurement

values, as well as a sound assessment, requires understanding of these

issues. Fault requiring repair of the bearing requires the identification

and understanding of the fan unit. The interpretation of the symptom as a

fault which requires the repair, requires special professional skill and

experience. Detecting a symptom does not mean a need for repair. The

need of a symptom based repair is set by the manufacturer of the fan

during the warranty period.

General installation instructions of the separate bearings are in the annex

Installing and removing separate bearings. Temperature guard limits are

presented in annex Sensor limits.

Detailed installation instructions for different bearing and housing types

can be found on the manufacturer's website www.skf.com.

Dust Control Systems Oy will assist in the acquisition of more detailed

instructions.

4.2.2 Lubrication

Before maintenance and repair measures, stop the fan from the

maintenance switch and make sure e.g., by written notice or with a

switch lock that the fan is not started accidentally during maintenance.

Ball and roller bearings are usually greased (SNL bearing housings). Oil

lubrication is used in special cases, such as when the speed is too high

for greasing or if the bearings need cooling (SONL-bearing housings).

Grease-lubricated bearing housings are equipped with grease nipples,

from which grease is pressed in by a grease gun.

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If the bearing housings have to be replaced, make sure that the grease

nipple place is positioned so that the grease can migrate into the bearing.

For the first lubrication of fan-axis grease-bearings, grease type and

amount is shown in the main assembly drawing. If the fan is not used for

a long period of time, add grease and check the condition of seals

visually from time to time.

In lubricated bearings there is an external level gauge, from which can

be checked the oil level and visually also pollution. In the oil

compartment is the so-called quit, which also splash lubricates the upper

part of the bearing. The addition of oil is done through the hole in the

cover of the bearing housing. At the bottom of the bearing housing has a

plug from which the oil is retrieved if necessary.

Clean the bearing housing and grease nipples before lubrication, so that

no dirt reaches the bearing with grease.

Too large amount of grease in the bearing housing can cause a sharp rise

in temperature and bearing damage.

Different types of oils should not be mixed with each other!

Operating conditions are significantly associated with the choice of oil

type. The user should pay particular attention to the final selection of the

oil suitable for the purpose! On inquiry, the manufacturer will provide

detailed instructions on the matter.

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4.2.3 Lubrication intervals and amount of grease

Lubrication interval depends on the rotational speed (n), the bearing

structure and the size (d = bearing bore diameter). With grease-lubricated

bearings, re-greasing interval is shown at the type shield (located at the

fan base), and in bearing assembly drawing.

With oil-lubricated bearings, Fuchs Renolin B15 (ISO VG 46) oil is

normally used as first-fill oil. First-fill oil is recommended to be

exchanged for the first time already after a few hours of operation, so

that the potential impurities in the oil compartment can be removed.

Fuchs Renolin B20 (ISO VG 68) or B15 (ISO VG 46) oil is normally

used after first-fill oil. However, all fans and working conditions are

individuals, so oil-types and oil-change intervals must be examined

individually. Contact manufacturer for more info.

In the selection of oil, the foaming, rust, as well as antioxidant properties

should be taken into account. Mineral-based oils are more suitable for use

in nitrile rubber sealing rings. When using synthetic oil the suitability is to

be checked individually.

More about lubrication of bearings and lubrication intervals can be

found in the manufacturer's website (www.skf.fi).

4.3 Electric motors

Start-up and maintenance is done in accordance with the instructions

prepared by the manufacturer of the motor.

In the protection of the motor, the frequency converter enabled

protections such as overload, over-current and stall protection, pump and

fan applications, as well as the squared load must be taken into account.

For more detailed maintenance and lubrication instructions, see the

engine manufacturer's maintenance instructions. Instructions comes

along the motor, and can also be found in the web site of the

manufacturer of the motor. For the electric motor’s re-lubricated

bearings, first-lubrication must be performed during commissioning.

First-lubrication must be performed according to motor manufacturers

instructions.

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4.4 Electrical connections

Electrical work must only be performed by qualified personnel on

machines when switched off, the power supply off and restart disabled.

Electrical wiring to the motor must be flexibility so that any moisture

does not enter the switch box. In addition, the fan should be equipped

with the so-called maintenance switch.

In the switching, installation and cable selection must be taken into

account the frequency converter manufacturer's and the motor

manufacturer's instructions for the approved implementation, which will

prevent possible bearing damage.

4.5 Hub seal

Normally a Teflon produced booklet type sheet ring seal which is

compressed into the rear wall of the casing is used as a hub seal.

In more demanding applications a tape box seal can be used wherein the

sealing is achieved by graphite tape squeezed into the packing. Over

time, the tape box may need to be tightened so that the graphite tape

remains sufficiently tight. Clamping nuts should not be tightened all the

way, because then the tape will tighten too tightly and create too much

heat. The cover part of the box is tightened and at the same time the

shaft is rotated by hand until resistance is felt on the shaft. Tightening

nuts are locked with the lock thread, so that they do not open during

operation.

In the Purso air box, gas is conducted into the box to prevent the gas

leaking from the inside of the casing from coming out. Different types of

slip-ring seals are also possible to use.

If the hub seal will have to be adjusted, the cooling disc guard as well as

the cooling disc must be removed, so you can access the hub seal.

Sealing type is presented in fan-specific main assembly drawing.

4.6 Switch

Detailed instructions for installing the switch are attached.

4.7 V-belts

Detailed instructions for installing V-belts are attached.

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5 Troubleshooting Problem Cause Solution

Rattle Wear of propeller blade Check/Change

Smudging of the propeller blade Clean with the steel brush

Loose/Worn bearnings Check/Change

Loose parts Check the mounting of the parts

Contact of moving parts Check the mounting of the parts

Alignement errors Realignement

Worn rattle dampers Check/replace

Instable installation location Check/replace

Twisted shaft Check/replace

Environment caused rattle Check instllation/installation

location

Improperly installed flexible

connector Check installation

Noise Abrasive parts Check the mounting of the parts

Loose parts Check the mounting of the parts

Improperly installed bearing Check installation

Excessive/improper lubrication Check/remove the excessive

lubricant

Improperly installed flexible

connector Check installation

Improper performance Wrong rotation direction Check

Damaged flexible connector Check/repair

Improperly installed flexible

connector Check installation

Worn propeller blade Check/replace

Wrong rotation speed Check/adjust

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6 Maintenance intervals

Short explanation of maintenance works. Weekly visual check of all the appropriate parts.

Also we recommend check coupling, belt parts and belt tightness, bolt tightness, impeller condition

and cleaniness, bearing and motor bearing lubrication in 3 month intervalls.

Recommended service intervals are part of the preventive maintenance program, the purpose of

which is to prevent the breaking down and to predict failures. Compliance with maintenance

intervals gives the customer valuable information about fan service, which can be used as part of

the company's own maintenance.

Check the condition of the guards

Check the condition of the flexible connections

Check the condition of the accessories

Check the condition of vibration absorbers

In case of oil lubrication, check the oli level

Make sure that the rattle of the fans has not increased

Make sure that the fan does not emit abnormal noises