ZHEDONG Valves are available in three bonnet designs.The first design is the Bolted Bonnet,with male-female joint,spiral wound gasket,made in F304L/grapthite.Ring joint gasket are also available on request.The second design is the welded bonnet,with a threaded and seal welded joint.On request a full penetration strength welded joint is available,The third design is the pressure seal bonnet,with a threaded and pressure seal bonnet joint.The check valves are also available in three design configurations.These are piston check,ball check,or swing check designs.

Construction is as follows

1.Full port or conventional port;
2.Lift type check valves;
3.Ball type check valves;
4.Swing type check valves;
5.Acceding to requirement equip inside spring;
6.Bolted bonnet with sprial-wound gasket,threaded and seal welded bonnet or threaded and pressure seal bonnet;
7.Socket weld ends to ASME B16.11
8.Screwed ends(NPT)to ANSI/ASME B1.20.1.
9.Disc can change for throttle type,needle type,ball type and check type

Main structural features:
1.This product has logical structure,reliable seal,excellent performance and nice design.
2.The seal surface is build-up welding with Co hard alloy,which is attrition-resistant,corrosion-resistant,has good friction resistant and long life.
3.The stem quenched and tempered,and its surface is treated by nitriding treatment,thus it has good corrosion resistant and friction resistant.
4.It has double seal capability,thus is more reliable.
5.The stem may show the position of lift,thus it is clearer.
6.The part material,flange and butt weld end dimension may be selected according to current operating condition and users'requi-rement,so that meeting the requirements of various engineering.