Good day everyone.

Have anyone here previously analyzed steel piping directly connected to FRP tanks? This is client requirements in our project. Being an FRP tanks, it has a significantly low nozzle load allowable which makes it very challenging to pass the loadings. In most cases, I resorted to increase the allowable loads which is still under verification by vendor. But my biggest concern is the 10" nozzle connected to pump suction nozzle. I can pass the nozzle loads but I'm thinking the minute vibration caused by pumps may create damage in shell/nozzle interface of FRP tank in the long term.

In addition, pump and motor assembly will utilize stilt mounting. You can check the link for one of the vendors.

http://www.basetek.com/products/stilt_mounting/

In this case Pump-motor assembly is not bolted on foundation but just resting on it. Pipe routing also is made very tight considering that pump can slide a bit to compensate the expansion and still pass the nozzle loads. That makes me more concern about the longterm serviceability of the FRP tanks.

Normally the FRP tank manufacturers ask for flexible connection between nozzle and pipe.

Regards,

I agree with Danb ... use an expansion joint. FRP does not usually suffer from fatigue damage and certainly not from the vibrations tht emanate from a centrifugal pump.

There are other issues to consider ... the tank wall is probably very flexible and that may be to your advantage. But also, it may flex when filled / emptied, afftecting your pump.

You may find that a simple filled arch rubber (neoprene) EXJ is adaquate without need for tie rods. Discuss with the EXJ vendor.