RENEWAL OF CRANE WIRE :
Disclaimer :
Explanation given here are general in nature. The wire changing procedure will differ case to case basis. Always refer to own ship's crane Manual as provided by yard/ Maker.
Remember " SAFETY FIRST AND SAFETY ALWAYS"
The following Crane wire renewal procedure is divided into following parts:
A Things required prior starting the work
B Procedure.
C After renewal.
A. BEFORE.
0. Check the Crane wire ( Luffing or Hoisting) running hours.
1. Refer to company SMS and or manual regarding this. And or ask company sup'td about the same.
2. Famous Deck crane on bulk carrier:
IHI, McGregor, MHI( Mitsuibishi) , Liebherr
3. Check last entry in Chain Register on-board.
4. Check Crane wire ( Luffing or Hoisting) certificate and make sure the same in engraved on new wire kept in store.
Main things to check is : Type and dimensions of thimble end, Diameter of rope, other end, type of rope and compare that with certificate.
eg: dead eye thimble 32 thimble 36......near the spliced end you can find the certificate number .
( P&I club matter)
5. Considering wire rope is ready now, Electrician must remove the limit switch. ( Care must be taken that prior any operation it must be done)
6. Things required are : Gantline rope coil, crowbar, woodem wedge, belt sling, chain block, spike, screw driver, plier, spanner set , plier, hammer, americal spanner, rags, burlap, ....etc...
7. Lay-up new wire on deck. Some prefer to take directly from drum ( if stand is provided ) It may cause frequent twisting during operation. So preferably lay up on deck the entire length of wire rope.
B. OPERATION ( Runner wire)
1. Hang the falling block with help of belt sling.
2. Now operate the crane and loose the wire drum keeping only 3-4 turn remaining on drum.
(As runner wire is very heavy so even 4-5 turn is better)
3. ( Plan how you want to take out old wire) ( Check crane maker provided you with small window on back of crane from where old wire can be easily taken out)
Note the small hole covered with flange with rubber packing. Also roller as seen in picture need to remove and put on floor or else shifting the wire is not possible, while operating the drum. ( For Runner wire in this** type crane .....other make and model may differ)
4. Remove the other end of wire inside machinery space.
Some maker have other method of ending this wire at machinery space.
WARNING: prior removing this end of wire ....take wire stopper on wire at suitable position inside machinery space.
Wire in vertical position is coming from top and horizontal wire is going outwards.
5. Now reach the top of crane with required tools ( Use heaving line ) and care must be taken regarding personnel safety. Personnel protective equipment must be worn.
You will find thimble end on top of runner wire (Picture shown fore representative purpose only)
Remove cotter pin and Nut . Tie rope knot with gantline rope which you have picked up by using heaving line. Attach that with wire rope.
6. Wire top thimble end has reached the hatch cover top &
wire in machinery space end has taken out.
Arrange Fitter ( welder ) lay up welding equipment ( As per maker joining new and old wire they recommend hemp rope.) But in most cases welding is considered. Prior to that
a. Remove thimble by cutting
b. Bring the plain end of new wire rope and join both together
before cutting
after welding
Seizing is done for both wire ends. and nut is placed in between in horizontal position.
WARNING : Take adequate care for any hot work carried on board. HOT-WORK PERMIT is must.
7. Heave the wire slowly. At the same time greasing can done manually by hand and or by viper machine. ( If stopper in place remove that inside machinery space)
www.lelubricants.com/viper-wire-rope-lubricator.html
8. Keep two person to wound the old wire on top of grating.
Old wire on top of grating ( for representative purpose only)
9. In drum part wire rope ( three turns or 4 turns as taken) will be moving from one end to other till the end of drum.
like this:
PICTURE X
8. Now when the wire rope reach the "x" end , stop heaving. Put stopper again and slacken the wire rope and bring it back to its original position by hand /scrapper(need to move three turns of wire rope by two person on either side of drum in machinery space) ........this step is to be repeated for about 4 times till you get the end of new wire rope. The operator must care and keep an eye on all around operation.
( about 4-5 times for Runner wire 260 mtrs long and about 2-3 times for luffing wire 108 mtrs long)
Precaution: keep eye on new wire rope
Keep eye on greasing part.
Keep eye on joint of both wire ropes.
Keep eye on floating block also.
When thimble of new wire is visible operate slowly as this end has to reach on top.
( REMEMBER THE GANTLINE USED TO LOWER THE THIMBLE OF OLD WIRE ROPE .......KEEP THAT IN MIND .....THAT NEED TO BE IN SAME POSITION .....AS THAT WILL USED TO PICK THE NEW THIMBLE.)
At time wire rope may run fast, loop may come , sudden speed may increase.WHEN EVER IT CROSS SHEAVES...( this must be instructed to person engaged in greasing as he may loose his cool thinking this is done by operator mistake)
SO WHO EVER OPERATING THE LEVER MUST BE PATIENTLY HANDLE THIS.
SEE PICTURE X AGAIN AND NOTICE THE OUTGOING WIRE( Horizontal) DIRECTION AND SIDE . Or else the outgoing wire will be act as obstruction.
keep burlap on floor to keep area clean
All hand signal to be discussed in tool box meeting itself,....as operator need to keep its operator cabin door open and machinery space sound will be too high.
9. Now the welded part has reached the machinery space....Take that out of hole. Stop heaving. Put wire stopper , if needed use two stopper as during adjustment wire may slip.
Cut the weld using electric cutter.
Old wire is now fully out on grating.
Pull the new wire-end inside by hand and put it in the socket ( nut bolt end ) and tightened.
( THIS PART OF WORK IS LITTLE TRICKY NEED ADJUSTMENT OF DRUM ALSO)
WHILE INSERTING NEW WIRE INSIDE LIKE THIS ......LIKE IN PHOTO ABOVE .....MARK IT AND DONT INSERT TOO MUCH .....OR ELSE WHILE DURING OPERATION IT MAY TOUCH THE FLOOR.
Also these nut bolt are mostly stud type.....so insert and tightened with lock nut properly.
Don't worry about the other two turns........ once the end is tightened by moving drum.......... the other two turns can be set in correct Groove.
Now two person needed to reach the top of crane with safety belt.
( REMEMBER THE GANTLINE USED TO LOWER THE THIMBLE OF OLD WIRE ROPE .......KEEP THAT IN MIND .....THAT NEED TO BE IN SAME POSITION .....AS THAT WILL USED TO PICK THE NEW THIMBLE.)
while tying the gantline with new thimble end of wire rope ...........give some space about 50 cm aft of thimble.......for following reason
1. It wont hang too much.......need to cross the jib and operator cabin glass clearly with any damage.
2. Person on top need some space to tie chain block to wire rope if required.
Use the gantline with mooring winch .....and communicate properly using walkie talkie and start heaving the thimble end of new wire rope.
As it reaches the top put the greased bolt/pin.......nut .....and tightened.
Remove gantline, stopper, chain block if any.....................and then adjust and heave........pick up floating block and remove that sling used for hanging the floating block.
Park the crane in parking position and put back the limit switch.
Close the hole with flange provided in machinery space and put back roller guide behind wire drum.
Note: If in doubt with length of new wire rope .....better measure that physically and also take measurement of new thimble. .....especially Diameter......and breadth..........some cases the thimble body may not fit the end point of crane.
Below is the thimble drawing .....dimension.
Clean the entire area and clear the soiled rags.
Remember : safety first and always.
K.Kaushik
very confusing
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