PIPE PROPULSION METHOD AND PIPE PROPULSION UNIT

PROBLEM TO BE SOLVED: To remarkably reduce the construction cost for an underground pipe by reducing the size of a starting shaft. SOLUTION: According to this pipe propulsion method, an underground pipe 5 is sequentially connected to the rear end of an outer cylinder 1 of a leading pipe 3, a connecting screw casing 6 is sequentially connected to the rear end of the screw casing 2 of the leading pipe 3, and the leading pipe 3 is propelled under the ground through the underground pipe 5 and the connecting casing 6 to sequentially bury the underground pipe 5. In this case, the leading pipe 3 is propelled under the ground in such a manner that the rear end surface of the underground pipe 5 is substantially flush with the rear end surface of the connecting screw casing 6 built in the underground pipe 5.