Bypass Plunger

摘要

A minimum parts bypass plunger includes a main shaft or pushrod extending through a hollow plunger body that incorporates flow passages formed in the adjacent surfaces of the pushrod or the internal bore of the plunger body. The pushrod is retained within the plunger body by respective head and tail pieces or caps that are locked to the plunger body by 360 degree crimps around the head and tail pieces. A one piece clutch is supported in the head piece. The pushrod, has an integral valve head that closes the flow passages when seated against a seat in the plunger body.

主权项

1. A bypass plunger, comprising:
a hollow cylindrical body having a longitudinal bore therethrough and external threads at first and second opposite ends for respectively receiving a head piece and a tail piece; a one piece pushrod configured as a shaft having a first end stem, a second end stem,a mid-section between the first and second end stems, and an enlarged valve head disposed between the mid-section and the second end stem, wherein the pushrod is slidably disposed within the longitudinal bore of the hollow cylindrical body between an open state and a closed state of the valve head against an internal valve seat at the second opposite end of the hollow cylindrical body; the head piece having a longitudinal bore therethrough for receiving the first end stem of the pushrod and internal threads at a lower end skirt thereof for attachment to the external threads of the first end of the hollow cylindrical body; and the tail piece having a longitudinal bore therethrough for receiving the second end stem of the pushrod and internal threads at an upper end skirt thereof for attachment to the external threads of the second end of the hollow cylindrical body; wherein the head and tail pieces are secured to the hollow cylindrical body by a 360 degree crimp that deforms the skirts of the head and tail pieces into a first preformed recess in the external threads of the hollow cylindrical body; and wherein the valve head of the pushrod is retained within the tail piece.