GRP/FRP watermain thrust restraint

[alsly]

If using GRP/FRP pipe for trunk watermains in questionable soils, I would want to restrain all bends using the manufacturer's joint restraint system. Flowtite has a restrained joint design which requires a nylon shear rod to be inserted into slots machined into the joint coupling and pipe.

1. Has anyone used this system? Does it provide strong and dependable thrust transfer?
2. Is it easy to install, considering the rod must fit into machined slots?
3. Have these joints failed for anyone?
Thanks,
Alex

 

[BarryEng]

This system was originally produced for the development of axial thrust in AC pipelines. The collar had a hole from the outside of the collar & went around the circumference of the pipe on the outside of the RRJ (& inside of the collar).

This system has also been used for FRP bore casings. I have seen these used for bore casings up to 500 mm diameter & (I think) several hundred m deep - so the principle (I assume?) is OK. The cable (again - I think) was a plastic coated SS wire.

Ask Flotite for examples of its use (you can ring the installers for independent info) &, also, test results.