• Steam and Mining Industries

Check Valves, Cast Steel

Steam & Mining Industries offers check valves in cast steel designed to close automatically by back pressure of the flow in order to maintain the flow in one direction, and to prevent flow reversal. There are two kinds of valves: swing type and lift type. The lift type is mostly used for smaller pipelines, and the disc is normally of 'piston' type and occasionally 'ball' type. Both are designed for the forged steel valves. Swing check valves are so constructed that one end of the disc is fixed to the body with the hinge pin, permitting it to open freely in one direc-tion. As opposed to the lift type, the swing type check valve is widely installed both horizontally and vertically. When the swing check valves are equipped in vertical pipelines, special atten-tion should be paid so as to secure a force to lift up the disc. Swing check valves are normally of cast steel and mostly in large sizes. The body-cover connection is usually of bolted cover type, but of pressure seal type for higher pressure service. Seats are of flat type, joint with the body being screwed, welded or integral. The eye-bolt is particularly designed to the cover of the larger sizes to facilitate carriage. The following special designs for check valves are available: counter weight fixed to the rotating pin of disc to control the disc movement, shock-absorbed, forced closings swing type reverse current check, tilting disc type-swing check valves for higher pressure service.