Ten thousand pound lost anchor retrieval methods at 600 ft

I am currently on a project that involves Extensive underwater operations. Coming from the tow wire hauling , dredging , and Workboat industry, my experience has not included anchor handling. The method I seek s special though. What do you do when you lose a valuable anchor at 600 ft. There is about twenty five feet of 2 inch chain on it. I have used the Orville Hook for retrieving lost tows but not something like this. Can anyone help with suggestions? Thanks…

[QUOTE=Dougan;113605] What do you do when you lose a valuable anchor at 600 ft. There is about twenty five feet of 2 inch chain on it. [/QUOTE]

What do I do? Write a statement of facts, get witness statements, write a non-conformance and try to keep a low profile for the next couple years. How to get it back? 600 feet is a lot of water and 25 feet isn’t much chain. Anyway I’m 0 for 3 so I can’t help, and that’s in a lot less water.

Gotten the anchor fouled on the bottom a couple times, used divers, but 600 feet? How much is the anchor worth?

An ROV and an Anchor Handler.

how bout a really big magnet?

seriously, in that depth without an ROV I’d say you’re wasting money and effort trying to grapple for it

[QUOTE=Dougan;113605]I am currently on a project that involves Extensive underwater operations. Coming from the tow wire hauling , dredging , and Workboat industry, my experience has not included anchor handling. The method I seek s special though. What do you do when you lose a valuable anchor at 600 ft. There is about twenty five feet of 2 inch chain on it. I have used the Orville Hook for retrieving lost tows but not something like this. Can anyone help with suggestions? Thanks…[/QUOTE]

That’s only 4.5 tons at 180- meter deep, not very specially heavy comparing to Ocean Freighter’s.
Got to deal with chains, use grappling hook, send diver down, or ROV, and find & hook the end of chain with the wire rope…
and that’s almost done. Use windlass or floating buoys to life it up…

I have an ROV with a limited manipulator. What type of hook is needed as pinning a shackle is out of the question.

You have not answered the question “What’s the anchor worth?”.

If it’s worth $10k, but will cost more to mobilize an ROV and have a vessel & crew to retrieve & resecure - best to forget it and move on.

I have the crew, fuel, and time. The anchor is not worth anything special but I want it back.

[QUOTE=Dougan;113636]I have the crew, fuel, and time. The anchor is not worth anything special but I want it back.[/QUOTE]

Engineers should be able to fabricate a grapple hook. Get it on the bottom and drag it over the chain. You might get it hooked into one of the links.

I was thinking the chain is plied on top of the anchor but if you can get it laid out along the bottom it will be a bigger target to hook

I’m o for 3 so take that for what it’s worth.

Thanks KC. We tried that. Thinking an Orville Hook might be best though it was designed to float while it hooks. What is your workboat experience?

[QUOTE=Dougan;113639]Thanks KC. We tried that. Thinking an Orville Hook might be best though it was designed to float while it hooks. What is your workboat experience?[/QUOTE]

What’s a workboat?

Doubtful you will get it with a Orville hook @ 600’ your best bet is a grapel hook with Orville type ends on it seen one before while on a cable lay job. The straight Orville hook would be tough to guess that it’s laying right on the bottom and dragging correctly.

what are we talking about here…jigging to snag the effing thing? this is simply nonsense unless you have a DP vessel on the surface with the ability to lower a grapple right on top of the anchor steered by an ROV but if the ROV cannot manipulate the grapple then the anchor is lost. No way in hell can you do this without an ROV that can manipulate the hook and connect it to the anchor!

You don’t think you could run a grid line of courses and snag it?

[QUOTE=rshrew;113652]You don’t think you could run a grid line of courses and snag it?[/QUOTE]

no, I don’t

I know you shrew. Western? Thanks for the opinions. The DP necessity suggestion is doubtful. Remember when somewhat precision jobs were done without whiz bang DP?

No big deal. Grapnel at 1.2 WD and make a few passes till you get it. Done that before DP and ROV’s were in the picture. The wire will tell you what you need to know. 25 year ago most all rigs were in that depth, and all were anchored…damn near normal operating procedure.

http://www.intermoor.com/services-5/mooring-6/mooring-equipment-13/grapnels-and-chasers-154

[QUOTE=anchorman;113666]No big deal. Grapnel at 1.2 WD and make a few passes till you get it. Done that before DP and ROV’s were in the picture. The wire will tell you what you need to know. 25 year ago most all rigs were in that depth, and all were anchored…damn near normal operating procedure.[/QUOTE]

sure piece of cake with hundreds of feet of chain attached and all laid out nice and straight but not with only 25’ of chain…that’s the difference. 25’ is nothing and might even be under the anchor

That is the proper reply. Thanks anchorman, I will look into a fitting grapel and hook it.

[QUOTE=Dougan;113670]That is the proper reply. Thanks anchorman, I will look into a fitting grapel and hook it.[/QUOTE]

So you say you have a small ROV available…have you seen the anchor at all? How is that 25’ of chain leading? What is the bottom like? All pretty important I’d venture to say.