Cracks Propagation Has Been Observed in FRP Flange 2

[Amir35]

After applying hydro static test on FRP piping,crack propagation has been observed on one of flange's body.it should be shaved(grinded)for depth estimation.we have no acceptance criteria for crack size on FRP flanges.I even have no idea about employing fiber glass polyester flanges with cracks.
Has anyone been experiencing same issue?I appreciate any advice

 

[LittleInch]

Seems to depend where on the body of the flange.

Cracks at the hub neck are not good, elsewhere might be acceptable.

Careful grinding to see if the crack has impacted on the glass fibres seems to be the key. If it has, throw it away and complain to the vendor.

https://www.dynaflow.com/wp-content/uploads/2015/04/Lecture-10-03-2011-Flanges-by-Dynaflow.pdf

has it both ways - hub cracks are bad, but then says a lot of flanges have cracks and it's all Ok!

when is a crack a superficial crack seems to be issue.

a sidelook at the Miami bridge disaster shows what happens when there is disagreement about cracks in a structure.



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

 

[LittleInch]

Was this gas piping which was loaded up with water for the hydro?

GRe flanges really don't like additional forces or being "pulled up" to make them fit

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

 

[SJones]

ISO 14692-4. The acceptance criteria for imperfections therein are, more or less, those of this document:

https://www.norskoljeoggass.no/cont...nes-for-ndt-of-grp-pipe-systems-and-tanks.pdf

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/in/drstevejones

All answers are personal opinions only and are in no way connected with any employer.

 

[Amir35]

Mr littlelnch;
All of your comments and posts are so useful and I always get valuable points from your suggestions. ...I am showing my respect to you (the person who not trying to sell everything he can sell). It is great that people like you are sharing their knowledge and not trying to sell it.stay strong
Thanks

 

[LittleInch]

Steve. A great post and excellent link.

Amir. Thanks for the kind words. I almost blushed.

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