Buried pipeline cleaning or boring-out system for restoration of old pipeline without cutting trench has chain drive for boring body with chain tensioning pulley in shaft

摘要

There is a shaft at each end of the pipeline (16) being bored out. An elongated body (4) with a boring head (5,6) at its front end is pulled through the pipeline toward the second shaft by a chain drive mechanism (1). The mechanism incorporates a vertically-reciprocating rod (18) with a pulley (2) with a locking device (9) on its lower end. The drive chain (3) passes over the pulley and two runs of the chain pass downward to two guide pulleys (10,11) side-by-side. The pulleys have locking devices (12,13). The first run of the chain is attached to the tip of the boring head and the second run passes through the elongated body and may be clamped (8) and the rear end of it.