×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Subsea Repair Clamp for Leaking Valve

Subsea Repair Clamp for Leaking Valve

Subsea Repair Clamp for Leaking Valve

(OP)
Does anyone have any experience of installing a clamp or similar onto a leaking valve? We have a several leaking valves and there are concerns regarding integrity (obviously) and we have been advised that preferred solution is to not operate valve or access gearbox etc due to concerns of making things worse and creating further leak paths (dodgy seals). I've been looking online but can only find examples of repair clamps installed on pipelines and tubulars, something similar would work but I have been unable to find an example. Any other ideas welcome...
Thanks

RE: Subsea Repair Clamp for Leaking Valve

Valves usually leak from the stem packings. Add sealent.
There are no clamps for valves that I know of.

RE: Subsea Repair Clamp for Leaking Valve

BI, how would one apply sealant to leaking valve packing under water, and presumably with the subsea line under pressure? Based on the question, it seems that the leaks are occurring at the valve connections.

RE: Subsea Repair Clamp for Leaking Valve

Sounds like the leak is through the stem packing out into the seawater ?

RE: Subsea Repair Clamp for Leaking Valve

With a weld-end valve, connections should remain relatively secure. Do you think they used flanged valves offshore? Not the best idea.

Sealant would have to be applied by divers or ROV using pressured grease gun.
Grease can be applied through lube fittings, even if line is under internal pressure. Hopefully the valve was ordered with lube fittings, right?

http://www.wegman.nl/downloads/WM%20-%20Installati...
Although that says not to inject into stem fittings

RE: Subsea Repair Clamp for Leaking Valve

(OP)
Thanks for responses. There are no injection ports provided on this valve, and I can't see us getting approval to drill one.

Why wouldn't you use flanged valves? 95% of subsea structures I've seen have flanged valves(North Sea), replacing a welded valve is a lot more expensive?

RE: Subsea Repair Clamp for Leaking Valve

Good welded valves from reputable manufacturers if they ever leak at all, will usually only leak a relatively small amount through the stem. Best is to order only highly qualified welded valves for offshore service. Ones that won't ever leak. You don't build offshore subsea pipeline systems with the intention to repair easily. Design with intent to never fail is by far the cheapest solution for long term offshore service. Sometimes at subsea tie-ins, flanged valves are the only practical solution, but if you don't have to use flanged valves, then don't.

RE: Subsea Repair Clamp for Leaking Valve

" We have a several leaking valves "

Where are the leaks?
Stem?
Body?
Body flange?
end flange?
Internal seal?

If stem what is seal arrangement? Can you post a cross section?
If internal seal what are seats made of?
Pressure?
Actuators / manual / ROV?

If you could find such a clamp, this would mean your valve would probably become inoperable. Is this acceptable?

what is access like?

Is it inside a structure?

Give us a bit of a clue here and you might get some more targeted responses.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources