Single Spring Pusher Seals consists of a very simple and compact design. A rugged conical spring is used to transmit the drive torque. The open single spring won't clog easily in viscous, polymerizing, crystallizing fluids and liquids with fibrous suspensions. In a single spring pusher seal, the shaft gasket move in relationship to the shaft. Pusher type seals can begin to leak when normal product leakage combined with face wear builds up to cause the shaft gasket to hang up.