Patent ID: 6269889
Filing Date: 2001-08-07
Classification: E21B

Abstract:
A ground piercing tool comprising:a tool body including a bursting head having a front, forward tapered end and a rear end, the tool body further including a plastic tubular member having a front end portion thereof attached to the rear end of the bursting head and extending rearwardly thereof, the bursting head having a rearwardly opening recess into which the front end portion of the plastic tubular member is inserted, and having one or more holes which penetrate from an external surface of the bursting head to the rearwardly opening recess;a striker disposed for reciprocation within an internal chamber of the tool body, the striker impacting the bursting head from behind and driving the tool through the ground;a reciprocation mechanism disposed in the tool body for reciprocating the striker;one or more fasteners inserted through the holes into the front end portion of the plastic tubular member to mechanically secure the plastic tubular member to the bursting head; anda plastic replacement pipe bonded coaxially to a rear end of the plastic tubular member.