Crack on FRP piping

[ssreekylm]

Hi..
Since I dont have much experience in FRP/GRP, Is any one can share the inspection requirements for the same?

Last day we had found one discontinuity on the FRP flange looks likes minor crack..So how can I ensure the integrity or what the repair method?

Is it possible to apply lamination on flanges?

Please help me to solve this...

 

[LittleInch]

Something like this perhaps attached?

or this

https://www.google.co.uk/url?sa=t&r...t4P378IvPAhXoDMAKHcT0ADUQFggqMAI&url=https://

http://www.norskoljeoggass.no/Globa...6keNTSeduu09qQ&bvm=bv.132653024,d.ZGg&cad=rjt

or this

http://www.maverickappliedscience.com/blog/264-why-inspections-are-key-in-maintenance-planning

You really need to get in some experienced inspectors with GRP otherwise you're just guessing.

Then work out why this bit seems to have cracked - looks like uneven forces on the flange?

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

 

[europipe]

Looks like the bolttorque was too high.
That's very nasty, I think You got to order the part again.

 

[ssreekylm]

But how can i ensure that its a surface crack or having more depth? I checked the internal surface and its perfect,there is no sign of damage.

What type of inspection is used in FRP to found the surface defect.(same that of NDT in steel)

 

[LittleInch]

Try reading the references provided, especially the first web link ( Norwegian oil and gas guidelines), section A3

It provides a number of photos which look exactly like your crack A14 to A17

You can actually X ray it, but the only way to make sure or get some real data is to grind off the resin layer and see how deep it goes and which layers it affects.

If it's started to break the fibres, or is more than 30% deep then you're in trouble.

Just because it isn't a through wall crack doesn't mean it's Ok. It's clearly been stressed beyond what it should have been or hasn't been made correctly

Either way FRP ISN'T STEEL, so don't look to that as a way to examine / fix this stuff. It needs proper examination by someone who knows what he or she is looking at and has seen similar things before.

This looks like the bottom flange of a vessel? Not easy to get in there to grind off some of the resin, but that's what you'll have to do.


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

 

[MaverickAppliedScien]

This would appear to be edge peeling of the overlay laminates which are attaching the flange to the other equipment. This may not be a flange issue, as much as it is an attachment overlay bond issue. There are very few reliable / accurate ways to determine the depth of the peel using NDE. The safest way to determine the depth of the damage is through grinding the surface laminates to find the end of the delaminated material.

Tom Haber
Maverick Applied Science

 

[r6155]

Try with liquid penetrant. See ASME X

Regards
r6155

 

[LittleInch]

All liquid pen does is tell you have a crack. Once you grind the crack out them it will tell you if you've got to the bottom of the crack.

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

 

[ssreekylm]

k,lets check with grinding and inspect thoroughly....

Thank you very much for your quick response and support....

 

[LittleInch]

Let us know what transpires and a few photos in return...

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

 

[chicopee]

It appears that the crack started at one of the stiffeners and propagated toward the bolt holes. Cause may have been due to some bending action. I would not take a chance with repair and determine cause before replacement with a new flange. Also contact the manufacturer for their opinion. To determine the depth, I would grind the surface.

 

[GenB]

UT. a certified experienced UT tech will tell you the depth of the crack.

 

[chicopee]

UT on a FRP body, is that possible GenB?

 

[GenB]

I think is the only option. A lot of articles are available on the subject of ndt testing of RRP. Here is one of them.

http://www.qualitymag.com/articles/...ng-of-fiberglass-and-carbon-fiber-composites.

GenBlr

 

[r6155]

chicopee
See ASME V AND X

Regards
r6155