Non-return valve for fluids - is fitted with welded seals around bearing pins for valve plate so that fluid cannot leak out at this point

摘要

The valve has a cast iron housing with bearings holding bearing pins supporting the valve seat for pivotal movement. The bearing is sealed by welding together two concentric rings projecting in near the mouth of the housing bore. The outlying ring is formed in the housing and the other ring is formed in a cover for the bore. The welded rings do not project so far as to abut flange spanning bolts of the two pipe flanges between which the valve is arranged.