Ground piercing tool with plastic body

Abstract

A ground piercing tool of the invention includes an elongated tubular housing having front and rear openings, a head including an anvil secured in the front opening of the housing, a striker disposed for reciprocation within an internal chamber of the housing to impart impacts to a rear impact surface of the anvil for driving the tool through the ground, a reciprocation mechanism for reciprocating the striker, and a tail assembly mounted in a rear end opening of the housing that secures the striker and reciprocation mechanism in the housing. A plastic tube forms the body of the housing, and the plastic tube is secured to the head. The reciprocation mechanism is preferably an air distributing mechanism that uses compressed air to reciprocate the striker. Such a tool can be used to install an underground pipe by welding a front end of the replacement pipe coaxially to a rear end of the plastic tube, operating the tool over a run to pull the pipe into the ground, and when the tool has reached the end of the run, disconnecting the tool from the replacement pipe.

Dependencies are inferred from the claim text.