Material recommendation for lifting applications subsea

[SiggiN]

Hi!

I'm looking for some suggestions for material for lifting applications subsea (max. 6 month submerged)

WLL = 1000tonns

I was thinking mooring chain steel qualities (R3, R3S, R4, R4S and R5), but would like to hear alternatives

Thank you!

Regards
Siggi

 

[TugboatEng]

What other materials would you consider? 300 series stainless is subject to stress corrosion cracking. Everything else is too dang expensive.

 

[EdStainless]

steel, lots of steel.
As TBE says, it is the only viable option.
Use good corrosion allowances and safety margins.

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P.E. Metallurgy, consulting work welcomed

 

[BenMacier]

Some alternatives would be to consider composites (e.g. carbon reinforced fibres) but the lack of understanding from offshore design engineers has resulted in very few utilisations in this industry compared to others with as much risk and expensive consequences.
So due to lack of track records, you won't get the authorities to sign in to your proposed alternative I am afraid.

* Finding a solution is great * Knowing how to implement it is fantastic * Believing it is the only one and best is naive ?

 

[Guest102023]

Crowdsourcing is not an appropriate approach to designing subsea structures and equipment.
There are established industry practices and codes that apply; I suggest you start by familiarizing yourself with those.

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

 

[WKTaylor]

Your lifting scenario is far-too skimpy on configuration/size, designated lifting points, accessibility, sea depth, currents, genera sea water conditions [tropical, arctic, etc], expected marine-life attachments... etc...

Regards, Wil Taylor
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