... :35 CrMo 4, to locking the valves in mud pump mould API Valve cover for mud pumpLocking cover belongs to cylinder parts ... City Qili Petroleum Mechanical Equipment Co., Ltd,specializing in mud pump,fluid end.Our products mainly include valve seat and body ... , valve assy, liners, piston, piston rod and others mud pump parts.Our products have already gained ISO9001 quality management ...