bloody wirelock!!!

[Savante]

ok, just spent the last 4-5 hours with pilot tech bashing hell out of a main lift umbilical to get it out of a bullet using the rough end of a 25mm diam bolt and the biggest bloody mallet we could find. we’ve had to chisel out wire lock to try and get it to shatter.

Has anyone got a good method of clearing a bullet of a mainlift umbilical. we got it out in the end, but I would really like to know if there is a "granny knows best" solution out there>?

[thinsub]

I have found either building a press that can be used to fit a hydraulic Jack or screwed down with some large nuts on some heavy thread bar usually works.

Usually means a different press to fit different types of bullet but does work pretty well.

Thinsub

[Savante]

cheers- we couldn’t get a hold of one but I think I’m going to try and get one for next time we’re alongside….

[thinsub]

Why don’t you make a press?

[wmb97]

if you can get away with heating the piss out of the main lift where it enters the wirelock…sometimes that helps. Some co’s complain as they’re worried about affecting the metallurgy of the bullet…..BS! Otherwise i’ve welded up a temporary ‘strongback’ arrangement and jacked it out with an enerpac…anyway you do it its a right bastard!

[Savante]

thinsub – I think we’ll definately have a bash at that – I was tempted to go for the thermal cycling approach but was really worried we’d deform the inside of the bullet – good to know someone else has tried that successfully.

Last night was a complete bastard. We had to take out the jb from the tms. Some swine had rounded off the bolts and filled the waterblock cable gland with heaps of scotchcast. We had to remove the whole thing – broke a left-handed tap, blunted two drills and then finally drilled the head off.

Oh yeah, it rained too!

[Ray Shields]

Sounds like fun 😀 Last resort is a burning torch to melt it out. Does the job but hellof a mess/smell!

A lesson to all to make sure the inside of your bullit is squeaky clean and smooth before pouring your Wirelock, as you may be the poor barsteward who has to take it back out later on!

[Stewie_G]

If you can throw the bullet in an oven for a few hours at around 400 degrees F (200 C) it should press out easier, assuming you have a big oven and press. The torch is the second best answer, just be careful where you put the heat and avoid the legs of the bullet that go down to the pivot pins. The bullets we made were 17-4 heat treated to H900. You can mess up the heat treat and also carburize the surface which leads to corrosion and possible failure. The DNV requirements for a new bullets is at least 4.5 times safety factor which includes the TMS, ROV and ROV thru frame lift capacity.

[Savante]

cheers stewie, we’re trunning tms, tether, sensor loadout and vehicle, combined mass of approx 950-1000kgs. I was going to do a static load test for 2 tonnes and leave a water bag hanging over the dockside for half an hour – 45mins and see if we have any movement on the bullet.

[Savante]

sorry – 4.5 tonnes…

[thinsub]

Warning !!

When using heat you have to be very careful as you can get some trapped pockets of gas which can explode in the wirelock, I have seen this happen and it can be very dangerous i.e. wirelock flying across deck. I think IMCA advise against it. That is why it is a always good to use a press.

[Savante]

thinsub- i’m sold – I’ll build the press!! 😆

[Anonymous]

hi
spray with silicone inside bullet before using wire lock.

[Stewie_G]

You don’t want to test the termination at 4.5 times the load, 2 times is more than sufficient. The 4.5 – 6 times will be near tensile failure for the machined parts. What ever you do, DONT SPRAY WITH SILICONE OR ANY OTHER MOLD RELEASE!!! The wirelock needs to stick to the metal or the forces created by sliding action into the taper can destroy the wirelock at less than the rated load. Also make sure you remove all the grease from the cable strands and clean them thoroughly.

Reterming the umbilical isn’t as bad as explaining why the entire system is sitting on the bottom.

[Savante]

4.5t = lloyds of london,

4.8t= dnv reccommended for this vehicle. phoned the manufacturer to double check.

the thing looks sweet, just waiting for the new wire-lock cast to harden.

Hell of a day to give up smoking…..

[Author]

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