Monel seizing wire for mooring shackles

jools
quite, i dont know why they rabbit on, the name is very descriptive, "seizing wire" says it all really doesnt it?
had a sh*t of a weekend. peed down! company was good at the club tho, brian the polisher, was 60, party went on quite late!!
stu
 
Lakesailor has the 2nd best option and one of very few choices.

The best option (by a very long way) is a welder.

Quote:
A combination of cable ties, seizing wire and peening the threads seems pretty good.

Don't know if I like her zinc plated shackles though :-)
 
Surely welding will change the metallurgy in the shackle, potentially reducing its strength. Insurance implications?

The conventional screw type shackle was banned for lifting operations offshore because they could undo. Bolt type anchor shackles were used throughout because they couldn't undo providing the split pin was used. I don't have a mooring, but if I did, that is what I would use.
 
I doubt whether the carbon content of most shackles is high enough for welding to have a severe effect on the metallurgy. Welding the pin to the eye on the outer end would seem to be an acceptable method of preventing the pin from coming out. Of course, it's no longer a shackle when you've done that! The professional moorings people on the Menai Strait weld everything up but don't use shackles, they bend rebar into a paper-clip shape and weld the long edges together.
 
vyv
all the rebar that i came across was strange in that when it was welded it became quite brittle, hi carbon content perhaps? it was always said in the oilfield that it was "crap" material. i know you are the metallurgist, what do you know about the content?
stu
 
[ QUOTE ]
Surely welding will change the metallurgy in the shackle, potentially reducing its strength. Insurance implications?

[/ QUOTE ]

It may do, I don't know. I'm just basing my comments on over 15 years experiance looking after 7000 moorings. Any shackles we find not welded get chucked or we weld them up. As mentioned above we also prefer (and do) use 'welded links' i.e 16, 20 or 24mm round bar bent like a chain link but with an overlap which we weld up. These are far superior, stronger and safer than shackles, not that shackles are bad.

Insureance implications - never had to find out, never lost a boat due to these connections. We can very easily prove welding and welded links are better so it should be no issue.

NOTE: If you do weld, do each end of the pin on the inside of the shackle body. Does not need to be right around just a big lump so when the thread goes the pin just can't slide out. Very simple and effective.

Obviously you can't reuse the shackle again but they are usually buggered after a couple of years and they are cheap anyway.

The last type of shackle we would use are 'bolt and split pinned' type. They are usually all high tensile and that's the last material you want in a mooring system beside stainless steel. Fizzs like a coin in coke.... spooky.
 
You must log in or register to reply here.

Share this page

Top