Sekisui Chemical Co., Ltd.

Junichi Nagatsuka

Hiroshi Sugahara

Tatsurou Baba

Masahiro Yamasaki

Yoshirou Sugiyama

A spiral pipe () is formed by joining edges of adjacent turns of a strip member () while helically winding the strip member using a pipe-making apparatus. A propulsive reaction force for moving in a winding direction of the strip member is imparted to a following strip portion () or a preceding spiral pipe portion () of the strip member by a propulsive reaction force imparting portion of the pipe-making apparatus. The following strip portion follows a preceding spiral pipe portion that has already been made into a pipe. A resisting force in a direction opposite to the propulsive reaction force is imparted to the strip member along the winding direction by a friction between a resisting force imparting portion and the strip member generated while the strip member is moved forward. In this arrangement, a diameter limiting frame can be omitted, and thereby, the pipe-making apparatus can be downsized.

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Shiga, Japan

Junichi Nagatsuka