I am dealing with a GRP piping system based on BS7159. the design temperature in 65 and pressure is 6 barg. it astonishes me everytime I check the outpout of operating case (W+P+T) since my piping system shrinks. could anyone confirm if it is because of pipes inflating due to internal pressure?

regards

Please contact manufacturer to request the material GRP properties (Sh, Elastic Modulus, Bending type and etc. and then input into the material data base. I think the incorrect data base should be caused of this failure. Because 6 barg is not too high to make the GRP failure.

I have found problem as you facing. I solve by input the correct data from Manufacturer.

whatare all the factors you fed into the system? Kindly get it
from the vendor. Whats the size of the pipe. Also, check the support span...

I used these data from Ameron Product. You can request from Vendor or Supplier if you use Ameron product. If you need from me in advance, please send me a email.