Wafer check valves

Dear Members,

Recently we were involved in an argument, with a contractor, over the correct orientation of a wafer Duo-check valve in horizontal pipe work. It has always been our instruction to have the double door hinge pins on the valve installed in the vertical axis and not the horizontal, as was done by the contractor. Our reasoning with this is that should a leg of the return spring break it is possible for the top door of the valve to remain open, when the hinge pins are installed horizontally, after the system is shut down. This condition, of the door remaining open due to a broken spring, is less likely to occur when the pins are installed vertically . The installation of the above was in a cold, clean water, pump discharge.

I would be interested in hearing of reasons for, or against the above.

Thankyou in anticipation.

Cheers,

Robin

[Non-text portions of this message have been removed] Received on Tue Oct 26 01:28:00 2004