Centrifugal Fans maintenance manual€¦ · 2.1 Fan types The fans are classified according to the...
Transcript of Centrifugal Fans maintenance manual€¦ · 2.1 Fan types The fans are classified according to the...
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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