Deep water salvage techniques

mojosavage · Feb 1, 2009

Hello all!

I am doing some research and wanted to tap into the expertise of this excellent forum.

I am interested in learning all I can about deep water salvage techniques that are currently employed as they relate to modern sunken vessels. I have found some sketchy info here and there on the web but was hoping that someone could point me to some better resources such as books, websites, or other materials on the subject. Your learned opinions are also welcome as to the most cost effective way to raise cargo from ships.

My focus would be on modern steel wrecks relatively intact with cargo in their holds in depths ranging from 500 - 3000 meters. I appreciate your time and help with this.

ms

coin_diver · Feb 2, 2009

Welcome to the site MS,
Well you are venturing into deep water and hence, deep pockets. The only way you'll be doing this is remotely and it is expensive. My current setup is only good to 300m and I can tell you the systems complexity and cost are prohibitive unless there is a distinct plan for recovery and comp.
Once you start looking at 500m you'll need a ROV ($500k up), tender (another $500k up) systems, staff, software, etc. Even to 1000fsw you'll choke up lunch.

Steel hulled vessels pose a problem in that you need to cut into them, find the cargo and extract. You'd almost be better off with a 1 atm suit if money is no problem.

Good luck

Darren in NC · Feb 2, 2009

Good advice, Mike.

Mo - plan on 12k-100k (US dollars) per day in a floating salvage plant. Sorima and Risdon Beasley were the old time pros at salvage. They used clam shell "grabs" to rip the ship apart later by layer, usually with a person in a submerged witness chamber to guide the boys up top. This technique (clam shell, not witness chamber) was used even as recently with the John Barry.This technique is not looked at as favorably anymore due to public demand for respect for the dead, so do your homework and find out how many lives were lost on the wreck.

At the depth you're speaking of, utilizing DP vessels (dynamic positioning), cranes and ROVs capable of this depth and work will definitely run the costs up quickly. You could safely estimate a 1500m project at 7-10 million. Do a search on David Mearns and email him about his costs. It's not cheap.

Best to you,
Darren

ScubaDude · Feb 2, 2009

I've yet to see an ROV that can burn metal underwater. I doubt it's a good idea to get a multi million dollar ROV anywhere near the vicinity of explosive hydrogen gas, pure oxygen, salt water, 10000 degree heat, and electricity.

You'd still need to have some means of delivering large quantities of Oxygen at depth, at 3000 meters good luck.

Let me know how that works out for you......

ropesfish · Feb 2, 2009

Hi there MS,
There is a pretty good article by Robert Marx in Wreck Diving- Issue 17-page 37 by Robert Marx entitled "Deep Sea Treasure Hunting" that gives a good historical overview of the subject with a bit of present day technology included.
I cannot offer specifics on the initial detection methods for such deep water other than sidescan sonar, etc. but the actual salvage will be much like ROV operations supporting offshore deepwater drilling. Operations at such depths are, as already mentioned, extremely expensive. Many of the work ROVs weigh several thousand pounds and require a sizable support vessel to launch and recover the vehicle.
Some of the companies that are active in this area of offshore operations are Perry Slingsby http://www.perryslingsbysystems.com/, Oceaneering http://www.oceaneering.com/index.asp, Deep Ocean Engineering http://www.deepocean.com/index.htmland others.
If you want/need to learn more about ROV's, their capabilities, etc. take a look at Ron's ROV Links http://www.ronsrovlinks.nl/modules/wflinks/. It is probably the best place to get started.
If you can get to New Orleans on March 3-5 there is the 2009 Underwater Intervention conference http://www.underwaterintervention.com/ which will have all the toys you could ever want/need/dream of in one place. A great place to gather information/network/etc....I'm an engineering student (at 53 yo) and am going to be there just to learn.
I hope this is of some help.

Bill Black
Roseland, FL

mojosavage · Feb 2, 2009

Thanks for the great information. I read about several companies that utilize a hydraulic grab system coupled with a dynamic positioning vessel that can operate in 3000 m water (or deeper). Are these systems built by a particular company or are they custom engineered and built as unique systems? If anyone knows about these particular systems or companies that make them that would be great.

I have also read about a company that has chain cut a vessel into sections and actually lifted those but I doubt that this was done in any deep water.

Salvor6 · Feb 3, 2009

Smit Salvage (no, thats not me) was the company that sawed the Russian sub "Kursk" in half and raised a portion. Click on "Our Work" and "Projects." Its at the bottom of the list: http://www.smit.com/.

Pete Smitt (no relation)

FISHEYE · Feb 3, 2009

The Hughes Glomar Explorer recovered part of a russian sub in 1974 in hawaii from a depth of over 16,000 feet.I was living in hawaii at the time and saw all the news reports that the ship was looking to mine for underwater manganese nodules.They say the sub was recovered 1200 miles from hawaii.But the ship spent most of its time in the molokai channel,which has depths down to 20,000 feet.The molokai channel is like the worst channel in the world.Any givin day the swells are well over 30 foot.I know cause i windsurfed from oahu to molokai during the summer of 1974,i sailed right past the glomar explorer.They blew thier horn at me and i heard something garbled like stay away.I was haveing too much fun in the giant swells to bother with them.it took me 9 hours to cross the channel.It would have been a world record at the time had i told anyone i was going.It took me 30 something hours to go back and something like 3000 tacks heading upwind.I slept for 3 days after that ride and sore as hell for a week.

rssharpetx · Feb 13, 2009

mojo,

We make one. Typically work in 1500m water. Support vessel approx 9k/day we do not need DP vessel. ROV swims out of a cage/battery pack. The only umbilical is fiber optic to ship. We use a weight and floats in lower section and catenary curve of cable to give us a big watch circle for ship. This eliminates high dollar support vessel with DP (poor mans dynamic positioning).

rssharpetx · Feb 13, 2009

Totally off subject but I just got back from testing ROV and used this pressure tank (huge) 90 in dia 20 ft deep 4500psi
Had to share. This was the largest chamber I have seen! also a great cup crusher