Patent ID: 8083505

Claim:
A barrel for use in a downhole pump, comprising: a) an elongated body made of a first material having a first hardness; b) a passage extending along the length of the barrel; c) at least portions of the body having a body inside diameter around the passage that is structured and arranged to receive a plunger, the body inside diameter having first and second ends; d) rings located at the first and second ends, the rings made of a second material having a second hardness, the second hardness being greater than the first hardness, the rings having an inside diameter, the ring inside diameter sized so as to produce a clearance with the plunger, the clearance providing a fluid seal; e) wherein the body inside diameter is smaller than the ring inside diameter, the body inside diameter being made of the same material as the barrel body, and the body inside diameter being structured and arranged to wear to the ring inside diameter.