Mech.pdf

ISO 9001:2008
O&M/CCE/EOT CRANE/REV01,dated:‐10.06.2012
Oldversiondated:‐10.06.2008
Page 1
CENTURY
SERVICE MANUAL
FOR
OPERATION AND MAINTENANCE
OF
ELECTRIC OVERHEAD CRANE
Page No.
A. Introduction 1
B. System Description 4
C. Operating Instructions 9
D. Maintenance Instructions 14
E. Trouble Shooting 20
F. Safety Instructions 23
G. Periodic Inspection Chart 28
H. DO’S & DONOT’S 29
UNIT-I
CENTURY CRANE ENGINEERS PVT.LTD.
16/6,MATHURA ROAD, FARIDABAD – 121 002
Phone : ( 0129 ) 4048863,4046661,4085663,64
Fax : ( 0129 ) 4048862
E-mail : century@centurycranes.com
UNIT-II
CENTURY CRANE ENGINEERS PVT.LTD.
Prithla Dhudhola Road
Prithla,Palwal
Faridabad,(Haryana)
PH:01275-262093,94
Fax:01275-262092
E-mail:ccecranes.plant2@gmail.com
Website : www.centurycranes.com
ISO 9001:2008
Page 2
A. Introduction
CENTURY CRANES have been evolved through of years of invloved experience in material
handling
and continuous up gradations. Century equipment is a highly versatile material handling device that
can be used to lift and move loads within its rated capacity. The appearance of the crane along with
its
main dimensions and clearances shown in the General Arrangement Drawing

The Crane moves on the gantry rails fixed on gantry girders. All cranes have three motions namely
the
Hoisting, Cross travelling and Long travelling. Following are the crane terminology / definitions you
would come across in this manual.
(a) CRAB : An assembly unit incorporating one or more lifting unit that traverses on the bridge
of the crane.
.
(b) SAFE WORKING LOAD :- Specified load which under is permitted to be safely handled by
the Crane under specified conditions.
(c) CYCLE DURATION FACTOR : - The ration between the period of loading including starting
and electric braking and the duration of the duty-cycle-expressed as percentage .
(d) HOISTING : The motion of lifting and lowering of the load in vertical direction. When
auxiliary arrangement is required for lifting & lowering of the load in vertical direction then it
is known as Auxiliary Hoisting. Generally the auxiliary arrangement is required in cranes of
heavier capacity.
(e) CROSS TRAVEL : - Motion of crab (s) along the bridge.
(f) LONG TRAVEL : - Motion of the whole crane along tracks on gantry girder.
(g) LIFT : - Maximum vertical Distance which can be traveled by Hook of the Crane.
TYPE OF CRANES : - There are various type of cranes used in Industrial application. Some of them
are defined as below : -
1. OVER HEAD TRAVELLING CRANE : - The Crane comprising of a bridge, supported by
end carriages capable of travelling along gantry rails fixed on gantry girders. Depending upon
the number of girders the over head travelling cranes can be termed as “Double Girder Crane”,
“Single Girder Crane”.
2. UNDER SLUNG CRANE : - An overhead Travelling Crane supported for its long travel
motion, from the bottom flanges of the tracks on which it travels.
ISO 9001:2008
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3. JIB CRANE : - A Crane comprising of cross traveling, hoisting and swiveling of arm
on which hoisting arrangement has been done. The arm of Jib Crane is fixed on column /
pillar as a cantilever. It can rotate about its axis through any required angle.
4. GOLIATH CRANE : - A Crane comprising of bridge supported by a legs and capable of
travelling on tracks at ground level.
5. SEMI GOLIATH CRANE : - A Crane comprising of a bridge supported on one end by a leg
and at the other end by carriages (s) capable to travelling along tracks, one at ground level
and elevated level.
SYSTEM OPERATION : -
Generally the Crane girder is of box type construction with necessary vertical diaphragm. The ends
of
girder are notched to receive the end carriages. The end carriage is connected to the Girders either by
welding or through bolts . The end carriage is of welded construction with plates/rolled sections.
The crane platform is laid with anti skid plates/checkered – plate protective handrails and toe guards.
In case of single Girder Crane the girders are made from fabrication/rolled sections. The ends of
girder
have end carriage welded/bolted. The girder flanges have cross travelling wheels of the hoist. The
whole girder with end carriage moves on gantry rail. The hoist performs the lifting/lowering, cross
travelling with load loads.

The Main Hoist drive is through motor & reduction gearbox. The motor is coupled to input shaft of
gear box through flexible geared coupling. The drum is connected with output shaft through flexible
geared coupling. The other end is supported on anti friction bearings. A creep gearbox is introduced
to
attain micro speed while hoisting/ lowering. A creep gearbox assembly consists of creep gearbox,
creep motor, brake drum etc. The similar functions of hoisting would be incorporated in auxiliary
hoist.
For both the hoist the Wire Rope is fastened on to the drum by Wire Rope clamps and the other end
is
wound round pulley and Bottom Blocks sheaves.
The cross travel motion has four wheels, two of them being driven on one axle. One of the wheels is
directly connected to output shaft of gearbox through coupling. The input shaft of gearbox is
connected to the motor through coupling. Similarly for long travel motion four wheels are there, two
of them being driven.
Bottom Block assembly houses the lifting hook and Rope sheaves. The hook swivels freely in the
Bottom Block assembly. Depending upon the capacity of crane Hook capacity, thrust bearing, sheave
diameter will be selected.
Limit switches are emergency stopping devices. Its functional performance should be checked to
ensure the perfectness of limit switches drive motion slowly through limits and check the motion to
be
stopped. Limit switches can be set at required distances to stop at limiting position.
ISO 9001:2008
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Power feeding arrangement required to give the supply to various operating parts of Cranes like
hoisting motor, long travelling motor, cross traversing motor, supply to control panel etc. There are
many type of power feeding arrangement, out of these some can be classified as : -
1. Taut wire type 3. Shrouded Bus Bar
2. Angle Iron type 4. Cable Reeling Drum
In Taut wire type power feeding arrangement a wire has been taught between tow ends on which
power
is to be transmitted. The freely moving trollies provided on taut wire carriers the power supplying
cable, hence, power is fed to required destination.
In Angle iron type power feeding arrangement-required length of angle irons have been fixed
between
tow ends. The quantity of angle iron depends on the input supply, and length of travel in our case
input
is three-phase supply, hence number of angle iron is four. On these angles one current collector
assembly is provided which takes current from angle iron and supplies the power through cables to
required destination.
B. SYSTEM DESCRIPTION
A) Brake
B) Limit Switches
C) Rotary Gear Type Limit Switch
D) Two Way Lever Type Limit Switch
E) Pendant
F) Flexible Gear Couplings
G) Creep Gear Box

H) Buffers
ISO 9001:2008
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I) Reduction Gear Box
J) Resistance Box
BRAKES :-
Brakes are very important equipment used in material handling equipment it holds the motion when
it
is required. In material handling equipment’s Brakes are various types some of them are classified
according to the type of supply, Shape of lining, Operating mechanism and are listed below :-
01. ELECTRO MAGNETIC SHOE BRAKE
02. ELECTRO MAGNETIC DISC BRAKE
03. ELECTOR HYDRAULIC THRUSTER BRAKES
These Electro magnetic brake may work on AC or DC supply these brake works on solon principal.
When the solenoid is energised an armature, which is linked with the shoe layer apart from brake
drum
to release the brake. When supply is cut off the mechanism comes to its original position under
spring
action and brake is applied.
Hence the brake is spring applied and it is released by electro magnetic these solenoid brakes
electrically released and spring braking is fail-safe device. Depending upon the shape of lining used
the brake may be named as Electro magnetic shoe brake (EM-SHOE) Electro magnetic disc brake
(EM-DISC). In Electro
Magnetic brakes the braking is usually applied to the extended shaft motor. The braking torque of
this
type brake is easily adjustable.
In Electro Hydraulic Thruster (EHT) braking movement given to the brake shoes by hydraulic
mechanism. In EHT brakes braking is done by lifting the thruster upward and thereby releasing shoe
/
brakes against spring force, hence braking is fail safe type. Thruster of EHT brakes are designed for
the load required in braking, at required torque.
The braking pressure on the shoes is transmitted from the springs by means of an extremely rigid and
simple lever tie rod mechanism. Braking is smooth and positive. Release of the brake shoes is
effected
by energizing the 3 phase thruster which overcomes the spring force and the shoes are moved clear of
the drum by the lever/arm linkage system.
ISO 9001:2008
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Owing to the extremely rigid leverage/linkage system there is no dead zone and the shoes open as
soon
as the thruster operates the lever. These type of linkage/lever makes adjustment very simple and
assembly of these brakes also much faster.
MAINTENANCE / SETTING :
i) The improved design of the leverage system and the linkage makes it possible to utilise only a
portion (70-75%) of the thruster stroke initially i.e. the time of commissioning of the brake
when the brake lining is new.

ii) The angle of the brake shoe being 70 degrees makes the replacement and maintenance of the
brake shoes at site easy.
iii) The springs are vertically mounted and the setting has been so adjusted that even an appreciable
wear of the lining does not have a marked effect on the braking torque. If the lining wear is
excessive the braking torque under goes a slight reduction and it can be compensated by
resetting the spring to original value, by means of the adjustment nut which is readily accessible.
The thruster motor is totally enclosed suitable for 3 phase 440 volt. C.50 cycles supply system. The
top bearing of the motor is grease lubricated and the bottom bearing splash lubricated from oil in the
tank.
LIMIT SWITCHES :-
Limit Switches are emergency stopping devices or these devices are used generally to stop the
Cranes/Hoist at its extreme ends. For example : When hoisting limit switches comes into action
hoisting will stop at ground level which will stop further hoisting downward and vice versa.
Similarly
is cross traversing & long travelling.
Contact & all mechanisms of limit switches should be free from dust and dirt one should inspect the
limit switches for its cleanliness. If required, limit switches can be set for intermittent positions also.
ROTARY GEAR TYPE LIMIT SWITCH :-
Rotary Geared type Limit Switches shown in the sketch are used on control and power circuits of
reversing drives to limit their rotation/movement within predetermined operating range.
It basically consists of heavy duty worm gear drive with a ration of 48:1. This worm gear unit is built
in a sturdy cast housing, which is bolted to the main body of Limit Switch which is also cast iron.
The
operating shaft of the limit switch, the contacts are shields etc. are housed in a dust tight, gasket sheet
steel enclosure. The Body of the contact is made of high grade melaine which is specially suitable for
heavy duty.
In all cranes this type of the limit switch is normally used to limit motion, if properly installed, this
unit
doesn’t require special attention afterwards.
ISO 9001:2008
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TWO WAY LEVER TYPE LIMIT SWITCH :-
Two/one way limit switch prevents over travel and over traverse. This type of limit switch normally
remains closed and cuts off power supply to stop the motors of the crane. This limit switch operates
when it reaches predetermined position, when the lever is moved over a projecting member fixed on
girder. The limit switch contacts automatically reset when it return to zero position due to spring
action.
The housing is of strong reinforced sheet steel of heavy gauge, the camshaft mounted on moulded
bushes of synthetic material. These bush bearing do not require any lubrication. The cams are also
moulded from synthetic material.
PENDANT :-
The pendant push button is a suspended frame which move along with the hoist. Pendant contains
push buttons, indicating light or some other optional items like emergency switch, key switch etc. the
number of functions used in pendant can be defined as number of ways of that pendant.
The push buttons have different functions depending upon the type of use, for example push buttons
may be used for hoisting up and hoisting down, cross traversing right & left, long travelling forward
and backward, rotation clockwise and anti-clockwise (in case of jib cranes). The push button pendant

may be of suspended type or may be of fixed type. Depending upon the site condition pendant would
be used. An emergency stop push button is provided to stop the crane/hoist in emergency.
FLEXIBLE GEAR COUPLING :-
Flexible gear coupling is used to join tow load acting or power transmitting members. In our case
flexible gear coupling is used to join output shaft of gear coupling one hub having interval teeth is
mounted on one member and on other member bush having external teeth is mounted, then
bush/splines meshes the hub to form the flexible coupling. Depending upon the power to be
transmitted conjuration of coupling would be designed. Generally coupling is mounted in motor to
input shaft coupling is mounted inside the brake drum.
CREEP GEAR BOX :-
To attain the specified speed reduction gearbox is designed. While for attaining micro speeds, a creep
gearbox is designed. Creep gearbox have sun & planet type gear arrangement. As in sun-planet gear
type arrangement have more reduction ratio hence it is used to attain micro speed. Generally for
creep
gearbox a separate motor is used to give input.
BUFFERS :-
Buffers are the devices to absorb shocks while impact. Buffers are of various constructions, but in
our
case buffers are of rubber type or spring action type. Generally in ling travelling arrangement spring
ISO 9001:2008
Page 8
type buffers are used and in cross traversing arrangement rubber type buffers are used. To attain good
efficiency of buffers end stoppers are provided.
REDUCTION GEAR BOX :-
The gear box is provided to attain specified speed. The reduction in speed from motor to output shaft
through reduction gearbox is done in various stages. Depending upon the reduction gearbox has been
designed. Number of stages of reduction shall be decided as per reduction ratio.
Reduction gearbox has all helical/spur gears. These gearboxes are filled with lubricant up to one third
of the total capacity of gearbox.
The lubricant used in reduction gearbox is Castrol Alpha SP-220 gear oil or any other equivalent.
Besides this an inspection cover is provided on the top of gearbox to visualise the condition of gear.
and gearing, an oil level indicator is also provided to change the lubricant after certain interval. In
reduction gearbox a breather plug is provided to escape all entrapped gasses/air from the box when it
is
in motion.
RESISTANCE BOX :-
It consists of corrosion resistant stainless steel in the form of grids. Suitable sizes of wires are used to
give range of current ratings. The resistor consist of a continuous resistance wire of uniform section
formed into required number of loops and bent so as to from typical grids. These are than mounted
on
mica insulated steel rods with mica washers between steel spares acting as grid separators.
MAINTENANCE OF RESISTANCE BOX :-
i) The resistors should be cleaned monthly at the insulators inserted between grids and earth.
ii) The terminal bolts and insulated spindles should be checked monthly.
iii) The resistor racks should be checked monthly.
C. OPERATING INSTRUCTION
A) Inspection before Operation (during commissioning)

B) Preparation for Operation (during commissioning)
C) Trial Operation
D) Procedure for Operating the Crane
ISO 9001:2008
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INSPECTION & PREPARATION BEFORE OPERATION (DURING
COMMISSIONING)
“ CENTURY “ Material Handling Equipments are tested under specified load and adjusted for
proper
operation before leaving the factory, it is supplied in assembled/semi assembled condition and should
be unpacked at the place where it is going to be used. Before the unit is placed in service, there are
several items that must be checked to ensure correct application and avoid service trouble.
1. Check the power supply from specification/G.A. drawing of the equipment. Check the voltage,
frequency and phase. The voltage supplied to the equipment must be same as indicated from
specification, otherwise over heating of the motor will reduce the lifting capacity and result in
improper functioning of all electrical components. Although all individual motors are protected
by HRC fuses, solid-state/thermal overload relay, single phasing and sequence preventers.
2. Check the tightness of all Nuts & Bolts and Screws.
3. Check condition of the Wire Rope making sure it is neither kinked nor twisted, since damage of
this kind renders the rope unserviceable. Also check the rope clamps.
4. Check that the Hook Block is not damaged and that all screws & nuts are secure. Check that
hook rotates freely.
5. Check that the rope sheaves rotate freely.
6. Check that the push button station is not mechanically damaged. Check the fixing of the cable
and supporting chain. Test the operation of emergency stop.
7. It is very important when applying power to the hoisting motor or the first time after
installation, that correct direction of rotation is obtained from the motor.
8. LIFTING END-SWITCHES
Checking that the end switch selector stops the hook course on the high and low extreme
positions. If this does not occur, then regulation of the end switch must take place, following
the instructions in the Installation, Operation and Maintenance Manual.
9. CROSS TRAVEL END-SWITCHES
Manually check the correct operation of the end switch. The end switch buffer will be
subsequently placed in order to limit the cross travel to the desired length.
10. BRAKES
Check that the brakes are operating correctly on load and without load.
ISO 9001:2008
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11. OIL LEVEL
Check the oil level
12. INSULATION RESISTANCE
This simplest method of checking the condition of motor insulation is to measure its resistance.
That of a dry and clean motor is high. Dampness or dirt normally causes a low resistance. If
the insulation resistance is not in accordance with the following instructions, the motor unit
must be dried out. In low voltage motors, the resistance should normally be at least 5 M Ohm

when cold and 1 M Ohm when warm.
13. END STOPS
Check the end and runway stops.
14. BUILDING
Check that there are no strange noises or vibrations in the different movements of the hoist
Mechanisms.
15. The overload device is normally adjusted to ensure that the hoisting motor is switched off when
the rated load is exceeded by 10 percent. Check the cut out load by using a 10 percent
overload, otherwise it will have to be regulated following the instructions indicated in the point
7 of the Installation, Operation and Maintenance Manual.
TRIAL OPERATION :-
01. Before operating the equipment, the operator should thoroughly accustom himself to the
working of the various motions. The brakes, limit switches & performance of controls should
be invariably checked up and perfectness ensured.
02. The above tests should be carried out with no load on the equipment. Operations must never
use the limit switches as a normal means of stopping the motion, limit switches are emergency
devices only. The operator should check the working and setting of hoist limit switchers after
all hoist rope changes and repairs likely to alter their correct position.
03. Before hoisting a load, the operator should ensure that the load has been reliably secured on the
hook. Before commencing the operation, he should give a warning signal for all worker to
withdraw themselves from the load to safe distances. The hoisting operation should be stopped
when the load is clear of the floor by a reasonable distance say 250 mm for the rigger to ensure
that latching of the load is perfect. Do not lift the load unless you are sure that it is properly
suspended from the hook or has been cleared by the slinger.
04. The load should be hoisted and conveyed in exact conformity with the signals given by
Authorised rigger, signaler or supervisors. Only one person should render the signals to avoid
confusion to the operation.
ISO 9001:2008
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05. Locate the emergency stop push button. The operator should obey the “STOP” signal,
irrespective of by whom it has been given. In the event of emergency or if the hoist should get
out of your control, immediately trip the circuit breaker/main contractor by means of this
emergency stop push-button.
11
06. It is desired to AVOID following practices wherever possible :
(a) Leaving a load suspended from the hoist.
(b) Hoisting and dragging a load on the cross travel at the same time.
(c) Carrying loads over heads of men working on the shop floor.
07. A load whose weight is near about the rated load should be hoisted in two stages. First lift is
about 200-300 mm clear of the floor, check the rigging and reliability of the brake. Then after
ensuring the correctness of rigging and efficient performance of the brake the hoisting operation
be continued.
08. While the load is being hoisted, conveyed and lowered no one should pull off the load by hand
for turning it, level out the load suing his own weight or release the holding ropes or slings
entrapped in the load falling zone.
09. The hoist should be positioned in such a manner that load is lifted perfectly vertical from the
start. It should not be positioned to drag the load with the hoisting rope inclined.

10. While the load is being hoisted, conveyed and lowered no one should pull off the load by hand
for turning it, level out the load using his own weight or release the holding ropes or slings
entrapped in the load. No one should move in front of the moving load or in the load falling
zone.
11. Never exceed the safe working load and also never run the hoist more than safe working period
as indicated by class of duty, hoist, which is indented while ordering the hoist.
12. Further the operator should be alert for :
(a) Changes in sound, which may indicate a developing, mechanical or electrical fault.
(b) Mechanical faults, such as loose key, couplings, bolts and the like. These faults may be
noticed whilst checking and carrying out the lubrication of hoist.
(c) Excessive side play during runway of hoist on the I-Beam.
REPORT ANY IRREGULARITIES TO THE APPROPRIATE DEPARTMENT WITHOUT
DELAY
13. Do the GO (General Overhauling) of hoist as per the schedule “ GO “ contains periodic
inspection. Lubrication and minor repairing.
ISO 9001:2008
Page 12
14. When leaving the hoist make sure that all the contractors are in the “ OFF “ position.
PROCEDURE FOR OPERATING CRANE :-
GENERAL : When an Operator resumes duty the very first thing he has to do is to carry out the daily
inspection procedure. Never use the hoist if it is not in perfect working condition, but report the
matter
to the concerned supervisory staff member or executive.
DURING OPERATION :-
01. Ensure that the load is vertically below the hoist in case of fixed hoist. If the hoist is provided
with the trolley bring the trolley just above the load. If the load is much away from the center
line of the monorail push it manually towards the center line until it is placed exactly below the
hoist. Dragging of the load on floor by hoist is to be avoided.
02. Ensure that the load securely slung on the hook, and it should be free i.e. it is not anchored on
the ground or stayed to any other object or to building structure,
03. Lift the load just above the floor to ensure that it is well balanced. If it is not well balanced,
lower it and adjust it for the balance. RAISE it again about a few centimeters above the floor
and check the hoist brake to ensure its perfectness.
04. If the brake is provided with the trolley, then traverse the load both ways and test the
performance of the trolley brake. If this brake has ensured its perfectness then the hoist is ready
for use. While raising further, checkup the spoiling of the rope on the drum and its smoothness.
05. Avoid impact loading caused by sudden lifting or lowering. Raise the load slowly to tension the
rope gradually and avoid swinging of the load. Inching the control before subjecting the hoist
to Normal/Maximum speed can do this. Sudden hoisting or lowering may cause breakage of
wire rope.
06. Do protect Wire Rope, hook fro weld spatter.
07. AVOID running of hoist more than safe working period.
08. DO NOT lift the load with excess sling rope hanging loose.
09. DO NOT allow any one to ride on a load being handled.
10. ABIDE all signals given by rigger or Signalman. (Refer standard hand signals for overhead
cranes and hoist).
AFTER COMPLETING THE HANDLING OF LOAD :- When the hoist is idle or when the operator

leaves the hoist, has to :-
ISO 9001:2008
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(a) Lower off all loads.
(b) Raise the hook to its highest position.
(c) Place all controls in off position.
(d) Place main switches off, if any and lock the switch box.
D. MAINTENANCE INSTRUCTIONS
(A) General precautions
(B) Maintenance – Electrical Parts
(C) Maintenance – Mechanical Parts
(D) Trouble shooting chart
GENERAL PRECAUTIONS :-
Maintenance and inspection are not only important for safe operation but also govern the efficiency
and services life of the crane.
In general precautions there are many points requiring attention for maintenance of the cranes but the
most important points are classified as following.
i) Lubrication
ii) Inspection for loosened parts
iii) Inspection of Electrical parts.
LUBRICATION :
Is the most important maintenance tool. Apply proper amount of oil or grease as specified in the next
chapter.
Worn or deformed and broken parts should have very much attention in maintenance. If the wear or
deformation found more than the specified limit as specified below, the part should be changed.
ISO 9001:2008
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LOOSENED PARTS :
Inspect all the fastened parts (nuts, bolts etc.) with special care. The maximum tightening torque
values for bolts are :
M 08 50 Kg Cm
M 10 100 Kg Cm
M 12 180 Kg Cm
M 20 800 Kg Cm
MAINTENANCE OF ELECTRICAL PARTS
Motors :
The feet of the motors should be free from dirt and surface on which motor is to be mounted should
be
properly cleaned and leveled. Motor and driven machinery must be aligned for avoiding stresses on
motor bearing and noisy operation. Checks free running of the motor by rotation the shaft.
Electric motors should be protected against water, oil etc. Terminal hooks should be carefully
inspected and cleaned. Before inspection the motor terminal box should be cleared or all dirt and
dust.
Bearing of motors should be checked and washed with petrol and lubricants should be added every
three months. It should be noted that the lubricant fill is not more than the level indicated.
CONTROL PANEL :

i) All the power and control terminal should be inspected at least once in a month. Every terminal
and connection at switch gears must be fully tight.
ii) Panel must be cleaned with compressed air to avoid accumulation of conductive dust.
iii) Insulation resistance between terminals and earth points should be checked on monthly basis
and any reading less than 0.5 Mega Ohm shall be disregarded.
iv) All fixing bolts of switch gears and mounting plate should be checked for their tightness.
INSTALLATION :
The contractors can be mounted on 35 mm Din Rail or directly. For direct mounting as below.
i) Drill Holes for mounting.
ISO 9001:2008
Page 15
ii) Check the current rating & operating coil voltage.
iii) Check operation of moving mechanism manually.
iv) Mount the contractor on the panel by using two M4 Screws.
PROCEDURE FOR CHANGING COILS
i) Disconnect cables/wires.
ii) Open side clamps.
iii) Separate top housing and base.
iv) Remove defective coils and replace new coil.
v) Assemble base and housing.
vi) Close side clamps.
vii) Connect cables/wires.
PROCEDURE FOR CHANGING CONTACTS : (Sizes D to F only)
i) Disconnect all cables/wire.
ii) Remove contractor forms its mounting.
iii) Open side clamps.
iv) Separate top housing & base.
v) Pull out the fixed contacts.
vi) Separate contact carrier assy.
vii) Take out contact springs by compressing.
viii) Insert new contacts carrier & springs.
ix) Assemble contact carrier & housing.
x) Push in new fixed contacts.
xi) Assemble top housing & bases close the clamps.
ISO 9001:2008
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LUBRICATION OF THE GEARS :
01. It is of great importance to maintain the required level of the lubricant, not only to prevent the
wear but also to maintain, silence in operation. The level of lubricant should therefore, be
periodically examined.
02. There is filler plug in every gearbox. There is also an oil level indicator in the form of
tapered screw plug or dipstick indication situated within 1/3 to1/2 the casting height from its
bottom. A Dipstick may in some case be provided on the side of the gearbox, for ascertaining
the level of lubricant in the case. The oil should be up to the mark indicated on the dipstick.
03. Every time, before opening the gearbox, it should be wiped off thoroughly with a clean brush
in order to prevent any foreign matter such as dirt or grit, getting into the gear box when the

lid is being opened for examination.
04. Replenishing the gear oil should be done with specified lubricant, however in cold seasons the
fluid might be slightly thicker. It is best to use a funnel for the purpose.
05. Before replenishing the lubricant, drain out the gear case completely, wash the gear teeth and
shafts with clean fresh brush, replace the drain plug. Pour some paraffin in the hoist. This will
thoroughly clean the gear and at the same time dislodge any small particles of metal or dirt
causing them to sink to the bottom and to flow out with paraffin when drained off. The gears
and shafts are to be re-examined for cleanliness. If required, repeat the cleaning process with
fresh paraffin. It is better now to repack the ball/roller bearing with fairly thick acid proof
grease to protect the bearings from abrasive action of the particles of metal which often come
out of the gears.
06. Never fill the gear box with excess of oil. Too much oil will result in definite loss of power
due to churning action and increase the frictional resistance. No thick oil should be used.
The golden rule is to use the recommended gear oil to use as thin oil as possible under the
circumstances and replenish after maintaining the required level always.
EXAMINATIONS AND REPLACING OF GEARS :
01. When the gear box is emptied and thoroughly cleaned with paraffin for replenishing the
lubricating oil, examine the gears thoroughly.
02. The sides of the gear tooth should be inspected for wear or burring. Any appreciable wear is
evident if two faces of any tooth is not symmetrical.
03. If the teeth have not been meshing properly there will be lack of parallelism on the crowns of
the teeth. The worn potions of the teeth surfaces will be indicated by a high polish while on
the unworn parts the original grinding or machining marks will be visible.
ISO 9001:2008
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WIRE ROPE MAINTENANCE :
i) The proper inspection and maintenance of wire ropes are most essential subject in crane
maintenance programme from the view point of “SAFETY”. The wire ropes and their related
components should be thoroughly inspected and maintained regularly on schedule
ii) As major inspection points, special care should be taken of securing rope anchors and clips,
finding out any defect on ropes at socket outlets and equalizers sheaves if used and performance
of ropes to measure were and damages of wires, deformation of ropes and their strands.
iii) The Wire Ropes should be lubricated through out periodically, taking care not to miss at socket
outlets and equalizer sheaves if used.
iv) When replacing wire ropes the unwinding of new ropes from reels should be carried out very
carefully to avoid harmful kinks.
WHEN TO DISCARD THE WIRE ROPE :
Steel wire rope deteriorates during storage as well as in service. The deterioration and the life of the
rope depends on factors such as storage handling operation service conditions maintenance etc. A
busy
rope will deteriorate faster. Generally accepted criteria for discarding wire rope in electric wire rope
hoists/cranes are appended below: -
01. When the outer wire have become difference in diameters of the portion of the rope subjected to
abrasion e.g. drum lead anchor lead, etc. are to be determined by measurement. The reduction in
the two diameters should be exceeding six percent of the original wire rope diameter.
02. When the rope has been subjected to severe over load or shock load at any stage.
03. When total number of visible broken wires exceed 10% of the total number of wires in the rope

at any portion in a length equal to eight times the diameter of the rope.
04. When there is evidence of severe corrosion like pitting. Fatigue in conjunction with corrosion
may affect the safety of the rope even at relatively early stages of corrosion.
05. When the rope has been subjected to localized distortion damage or kink which disturbs the
balance between the various strands of the rope and various wires in any strand.
06. When the diameter of the rope has suddenly decreased at any portion, of when the length of the
lay has suddenly increased.
07. When the core of the rope is collapsed. When the core has collapsed the strands will tend to
flatten out and deformation may the localized.
08. When one/more strands are found broken.
ISO 9001:2008
Page 18
09. When a bird cage is formed anywhere in the length of the rope.
Wire ropes must always be kept lubricated to protect them from rust and abrasion. Before applying a
fresh lubricant, the strands must be cleaned by a brush without opening. The rope should not be
cleaned by any grease solvent. When the rope is clean and dry apply the recommended lubricant by
an
ordinary paintbrush or a soft wire brush.
ROPE INSPECTION :
For machines in service all running rope should be visually inspected each working day for
distortion,
kinking crushing unstringing bird caging main strand displacement, core protection, loss of rope dia
in
a short length narrowing of rope at any portion of its length of unevenness of strands general
corrosion
broken wire or strands core failure etc. On the rope only surface layers are needed to be examined.
No
attempt is to be made to open the rope. End connections of the rope should be examined for damage
of
corrosion. The inspections are for evaluating whether more detailed inspection of the rope of
discarding of the rope is needed.
SHEAVES AND DRUMS :
The sound profile of grooves in sheaves and drum is essential for reasonable rope life the grooves
should be inspected periodically and the necessary counter – measure should be taken if they show
unusual signs e.g. excessive wear, scoring by wire rope etc.
The correct and orderly winding of rope on the drum is also essential to prevent the early failure of
wire ropes, therefore any of disordered winding of rope should be eliminated.
WHEEL AND WHEEL ASSEMBLY
Generally all wheels are closed die forged from medium carbon steels. The wheel dimensions have
been designed according to the type of loading, rail size, etc.
As normally wheel treads and flanges were of very slow degrees, if excessive wear is detected in a
short period, check the alignment of wheel and set the distance from wheel and ‘I’ beam to ensure
proper clearance between wheels & beam.
The Wheels treads and should be free from oil, which may cause the wheel to slips. The wheels are
shrink fit to the axles and the driving wheel is coupled to output shaft of gearbox or to motor pinion
directly as required.
TROUBLE SHOOTING CHART

S.No. DEFECTS POSSIBLE REMEDY
CONSEQUENCE
01. HOOK
ISO 9001:2008
Page 19
1.1 Crack in the hook Hook failure Replace hook
1.2 Excessive wear and Hook failure Replace hook crane operation
damage to working until procurement of hook.
area of hook (wear
over 5% on height)
02. PULLEYS
2.1 Uneven wear of rope Rapid wear of rope If non-uniformity of wear is over
2mm wise correct surface by
re-machining.
2.2 Rope & Sheaves do Damage to rope and axle Check bearing
not rotate uniformly.
03. DRUM
3.1 Damage on working Eventual failure of the Replace drum
surfaces of drum drum
3.2 Wear out of the drum May lead to breakage of Replace drum
surface over 10% of
wall thickness.
04. WIRE ROPE
4.1 Breakage of wire in Failure of rope Replace rope if the breakage is
strands. Beyond the 10% of total wire.
4.2 Twisting of rope Eventual damage to rope Eliminate reason for twist.
05. BRAKES
5.1 Wear out of brake lining Inefficient breaking and Replace lining if rivet of part of
damage o drum. shoe touches the drum.
5.2 Excessive wear of hing Improper operation Enlarge holes and put over size
pins. Pins.
5.3 Heating of drum Damage to lining Check brakes release and set `
properly.
5.4 Inefficient braking Excessive load slip Correct Spring tension.
ISO 9001:2008
Page 20
of brake coil.
5.5 Frequent burning of Brake failure to open Check for excessive spring tension
and correct magnet gap.
6.0 GEAR BOX
6.1 Breaking of tooth Jerky operation and Replace gear or repair if
further damages to gear breakage is small.
6.2 Wear of teeth Excessive backlash and Replace if wear is more than
jerky start and stop 0.5 mm.
6.3 Crack in body Final failure Replace gear.
6.4 Gear box getting Gear deterioration Replace oil

over heated
6.5 Oil leakage Gears running dry Apply shellac to joints. Replace
damaged oil seals tighten bolts &
fill oil.
6.6 Vibration in gearbox Breaking of shaft or Tighten bolts. Check alignment
couplings.
07 COUPLINGS
7.1 Loosing of bolts Damage to bolt & coupling Tighten bolt. Use lock washer.
7.2 Hole wear out Jerky start and frequent Enlarge holes & use oversize bolts
loosening of bolts
7.3 Surface Cracks Ultimate failure Replace couplings
7.4 Key damage Shearing of key and Replace key and repair keyway
damage to shaft if damage
08 BEARING
8.1 Heating of bearing Premature failure Replace bearing
8.2 Jerky running Failure of Bearing Replace bearing
8.3 Holding bolts going loose Damage to bearing Tighten bolts
ISO 9001:2008
Page 21
09. WHEEL
9.1 Non-uniform wears Jerky running and further Turn wheel to uniform size
of tread damage to wheel and surface.
9.2 Excessive flange wear Damage of bearing Check well and rail alignment
10. ELECTRICAL
10.1 Main switch (contractor) Line discontinuity Check voltage in all three lines
in operation Check whether main switch is on
Main fuse burnt Check all the fuses and replace
Burnt fuse.
11. DEFECTS
11.1 Wear out Control switch defective Check control switches & replace
if defective.
11.2 Mechanism operates One of the limit switch Check and repair the limit switch
in one direction only. contacts not closing
11.3 Motor fails to start Single phasing Check fuses and replace if one fuse
burnt out. Check voltage in all
phases. Check protective devices.
Defective stator winding Check whether there is discontinuity.
Rectify if it exists.
11.4 Motor runs in wrong Supply phase interchanged Reverse phase and recheck limit
direction switch operation
11.5 Motor does not develop Brake not opening Check brake setting. Adjust brake
sufficient torque properly clearances and spring tension.
11.6 Motor heating up Short circuit in winding Check phases and correct short
circuit.
Overloading Check line current and if excessive
find out reason and rectify. Avoid
excessive jogging.

Low voltage Check voltage and do not operate
it below 360 V.
11.7 Heating of motor Improper lubrication Clean bearing and re-lubricate
ISO 9001:2008
Page 22
11.8 Brake lifting noisy Low voltage Check voltage
F. SAFETY INSTRUCTIONS
A. Weekly checks
B. Monthly / Yearly checks
C. Periodical inspection Chart
SAFETY RULES
As we know that a check for faults which can be seen or heard is called INSPECTION and a more
through inspection which may or may not involve dismounting or use of testing equipment is called
follow the safety rules one should follow the regular inspection.
Regular inspection and periodical inspection are particularly important as they are the only means of
detecting potential hazards which could lead to accidents. The following are the routine inspections/
examinations to be carried out on crane.
01. Weekly Inspections : By the Operator when he resumes daily duty every day / shift.
02. Monthly Inspection : By the service Mechanic or Supervisor.
03. Yearly / Annual Inspection : By the Senior Authorised Executive within the organization
or from outside for testing.
WEEKLY INSPECTION
01. CHECK UP that the equipment is quite clean otherwise get it cleaned. The tackles and
attachment to be used are also likewise to be treated.
02. CHECK UP that the wire rope is not dry and is not damaged. Lubricate if dry.
03. CHECK UP the lubrication oil level in the gear box fill up to indicated level, if required.
ISO 9001:2008
Page 23
04. CHECK UP freedom of operation or the hook swivel, sheaves, etc.
05. CHECK UP all functional operation mechanism without load such as brakes, limit switches,
Sheaves, drums, wire rope spooling, hooks, etc.
06. CHECK UP that all guards like rope guard are in position.
07. ENSURE that grease and oil are removed from all walking surface.
08. When load is first lifted, check up the hoisting and trolley brakes, the load is raised only
by a few centimeters above floor.
09. Never operate the hoist if any mechanism does not function. Report to concerned executive
for getting the effect removed.
MONTHLY INSPECTION
(MAY BE THREE MONTHS INSPECTION IF THE UNIT IS LESS USED)
01. Carry out all daily inspections specified above.
02. INSPECTION the entire unit for structural damage such as distortion crack, dents, bend
corrosion, etc. carefully inspect all welded connection for cracks, paints flaking and cracking
may indicate potential damage.
03. INSPECT sheaves drum, etc. for any crack or damage.
04. INSPECT pins ,bearings, shafts, gears, looking devices, hook blocks, etc. for any damage.

05. CHECK UP the wear of brake disks or shoe linings. Change the part if the wear is excessive.
06. CHECK UP for loose bolts or studs. DO NOT Tighten loose bolt but renew the part with fresh
one.
07. CHECK all control mechanisms for excessive wear of components for contamination by
lubricants of other foreign matters.
08. CHECK UP that all exposed moving parts are well guarded.
ISO 9001:2008
Page 24
YEARLY EXAMINATION
(THIS LOAD TON BE CARRIED OUT ALSO TO HOISTS SUBJECT TO SUDDEN OR
UNUSUAL SHOCK LOADS OR TO MAJOR REPAIRS)
01 The load hook should be thoroughly examined for swivel and also for any distortion elongation
cracks, etc. If in the opinion of the examiner the hook is to be discarded it should be scrapped
and replaced. Even if fresh hook is not readily available the hook should be discarded and the
hoist idled until replacement of hook.
02 The entire mechanism attachments chains ropes sheaves drum, etc. should be thoroughly
examined for any crack or damage. If some defects found, have it replaced with a new one.
03 SUCH Examination should be carried out for slings and tackles customarily used with the hoist
under inspection.
04 The gear box should be opened, oil drained out, all gears pinion shafts, etc. thoroughly cleaned
and then FULL UP the gear case with fresh oil as per instructions given under the heading
GEAR BOX MAINTENANCE Broken or distorted parts if any should be replaced, bearings
should be thoroughly examined. In case of play between shafts and bearing, replace the
appropriate part or bearing or both.
05 Brakes should be examined to wear and slackness. Any lining or part required to be renewed
should be replaced.
06 CHECK UP all rectifications / replacement records for such rectification or replacement done
after the previous annual inspection to ensure that such rectification/replacement need not be
carried out again.
07 IN CASE any rope of hook, etc. had been replaced after the previous annual inspection, the
certificates pertaining to those parts should be verified.
08 CHECK UP the proper function of all oil holes, oil ways, grease nipples/cups, oil level
indicators etc.
09 CHECK UP grease packed housing of ball/roller bearings.
10 CHECK UP if wire rope is fairly lubricated. It it is dry, get it lubricated.
11 CHECK the equipment for operational test with rated load or with maximum load generally
handled. Test the function of brake limit switches, control panel, etc. thoroughly.
ISO 9001:2008
Page 25
LUBRICATION
The correct lubrication of component is one of the most essential parts of hoist maintenance.
Bearings,
Gears, Gear Couplings, Wire Ropes, pins should be lubricated regularly with correct lubrication chart
POINT OF
LUBRICATION
ACTIVITY FREQUENCY OF

LUBRICATION
RECOMMEND
1. Gear Box
2. Motor
3. Wire Ropes
4. Geared Coupling
5. Bearing Housing
6. Equalizing Pulley
7. Hook Bearing
8. Thruster
9. Plummer Blocks
Changing Oil
Greasing through
grease Nipple
Greasing by hand
Greasing by hand
Greasing through
grease Nipple
Greasing through
grease Nipple
Greasing through
grease Nipple
Oil Can
Greasing through
grease Nipple
Once in a fortnight
a) 400 hrs. for new
Gears Pinions Pairs
Once in six month
Once in a Fortnight
Once in 3 months
Once in a week
Once in a week
Once in a Month
2000 hrs.
Once in a Week
EP-90
Servo 2 or 3 Grease
MP
Servo Coat 140
Servo Mesh 40
Servo Coat 140
Servo gem EP 2
Servo gem 3
Transformer Oil
(Castrol make)
Servo gem 3
EQUIVALENT LUBRICANTS
INDIAN OIL BHARAT REFINERIES HINDUSTAN

PETROLEUM
Servo Gem 2 or 3
Servo Grease MP
Shess Multi Purpose Grease 3
--
HP Multi Purpose Grease H
--
ISO 9001:2008
Page 26
Servo Coat MP
Servo Coat 140
Servo Mesh 40
--
Cardium Compound
Macoma Oil H
--
Hytak F 30
Gervil EP 3
PERIODIC INSPECTION CHART
DESCRIPTION WEEKLY MONTHLY QUARTERLY ANNUALLY
Fastening bolts of Motors,
Brakes, Gear Box, Rope
Drums, Sheaves, etc.
* * * *
Bridge Grinder & End
Carriage Joints
(bolted/Welded).
* * * *
Brakes Lining * * * *
Brake Solenoid gap * * * *
Braking Performance * * *
Gear Box Noise level,
leakage’s
* * *
Lubrication of various Parts * * *
Motor – terminal
Connections
* *
Hook-free rotation/swiveling * *
Alignments of Motor * *
Contractor’s tip * *
Limit Switches Operation * *
End buffers for CT & LT *
All structural joints & welds
Wear off
*
Wear of Wheel flanges *

Replacement *
Gear/Pinion Wear *
Pitting & Wearing of Hook *
Hook nut & it locking
Rope Grooves on drum *
ISO 9001:2008
Page 27
Condition of pendent
Push button, circuit breaker,
Cable, etc.
*
DO’s and DONOT’s
Crane must be operated by a regular trained operator.
1. Read START OF CRANE
2. Neverleave the Crane without switching‘OFF’main Contactor
3. Always operate Crane with care and safety
MUST
READ
ISO 9001:2008
Page 28
DO’ S & DON’ TS
DO NOT DO
X Do not lift load more than rated capacity
SWL of the crane.
X Do not operate with twisted,kniked,or
damaged wire rope.
X Do not operate ifthe Rope is not seated
in the groove ofsheaves.
X Do not lift unless sling is properly
Centered on the Hook.
X Do not lift the load in inclined position ofrope
X Do not operate micro motion for a longer period
of time, instead use main motor.
X Do not operate ifany ofthe limit
switches is not functioning.
X Do not lowerthe hookbelowthe point
where less than two soundsofrope
remain on drum.
X Do not leave crane unattended with load
suspended on theHook.
X Do not permit load to contactobstacles.
X Do not exceed recommended dutycycle
Of the crane.
X Do not use Hoist rope assling.
X Do not divert driverattention where he
Is operating the crane
.
X Do not use travelmotion to pull/push
load across thefloor
X Do not use the crane outdoorsunless
weatherproofed
X Do Not carry out operations ifthe

clearance betweenHoist body and bottom
has reached 150mm.
Test all limit before the start ofeach
shift.
Blow sound warningsignalbefore the
travelmotion begins
Balance the load on the sling before
lifting it more than 10inches.
Test brakes before lifting nearrated load.
Lift the load for few inches and test the
brakes before lifting to actualheight
Knowstandardhandsignals
Use manufacturers operating instructions
Check lubricants at properintervals
checkfor propervoltage balanceand phasing
of electricalsupply.
Tight dog clamps at regularintervals
29

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