The plunger is assembled with a hollow plunger sleeve, a center connecting rod, an upper connector and a lower drop to seal against the bottom of the sleeve on each upstroke of the pump. The drop and sleeve are inlaid with a hard Stellite lining that resists wear and corrosion.

    The Loc-No® Plunger has two influences that help it open on the downstroke without relying on pump compression. The movement of the plunger rod is pushing the drop away from the plunger sleeve and the friction between the plunger sleeve and the inside of the barrel tube causes the plunger sleeve to resist downward movement. When the drop moves away from the plunger sleeve the fluid/gas mixture is free to flow up through the plunger as it falls through the fluid gas mixture. On the upstroke, the sleeve seals against the drop and lifts the fluid/gas toward the surface.

    The Harbison-Fischer Loc-No® Plunger is a proven product that is an inexpensive replacement for the plunger, plunger coupling, traveling valve and seat plug in a standard pump.