Angle seat valve is closed (open) with spring force. When the piston is actuated by compressed air, the valve is open(closed) For the double acting type, the valve is open and closed by compressed air.
Y type shape enlarged the flowing section, which could raise the flux by 30% and make flow more smooth.
The valve stem is AISI 316 with strong anti-corrosive ability. The PTFE seals are in wedge shape, which help and lubricate itself automatically.
The cylinder material is stainless steel. lubricates automatically, and rolls freely 360°.