Suction inlet box for reciprocating pump - has sieve scraper ring attached to inlet non return valve

摘要

The inlet has a casing (1) bolted to the suction connection of the pump. The casing contains guide ribs (6) which position a non return valve (2) and limit its upward movement. The valve seats on a lip formed by the bottom of the casing. The bottom half of the casing has an annular opening below the valve seat. This is covered by a filter sieve (3) which provides an inlet filter for the pump. The non return valve has a stem projecting below it which carries a spider (5) with a scraping ring (4) on its circumference. Every time the valve rises the scraping ring scrapes the inside of the sieve and thus keeps it permanently cleaned, and also helps to reduce corrosion.