... :single stage Summary Based on the similar imported equipment, YL series activated sludge pump is a kind of horizontal single ... 1Cr18Ni9Ti, 304,316L, Duplex Stainless Steel. Model significationStructural drawing of YL series activated sludge pump 1.pump body 2 .impeller nut ... mechanical seal 7.static seal 8.mechanical seal spring9.bracket 10.crease nipple 11.sleeve 12.spring seat 13.cooling water ...