Sekisui Chemical Co., Ltd.

Kouzou Makino

Hiroaki Kondou

Ayaka Kitagawa

Yoshihiro Inui

Amiko Sakamoto

Shintarou Umeyama

Tsuyoshi Katou

An electrofusion joint includes a tubular main body, a stopper portion, a first heat generation section, and a second heat generation section. The tubular main body includes a joint receiving portion. The stopper portion projects inwardly on an inner surface of the tubular main body. The first heat generation section includes a first heater wire wound and arranged at the joint receiving portion. The second heat generation section includes a second heater wire wound so that wound parts of the second heater wire are adjacent to each other and the second heater wire is in the stopper portion. The first heat generation section includes at least one heat generation portion in which the first heater wire is wound so that wound parts of the first heater wire are adjacent to each other.

Electrofusion joint and fusion method

An electrofusion joint includes a main body and a heating wire. The main body is configured to be connected to a resin pipe containing a thermoplastic resin. The heating wire is in the main body. The heating wire includes a conducting wire and an insulating cover film that is around the conducting wire. The insulating cover film has a melting point of at least 230 degrees.

Electrofusion joint

A multilayer tube is provided which suppresses the amount of calcium and organic component leaching to a low level and which can be realized as a tube that has mechanical properties at 60&#xb0; C. This multilayer tube includes a first polyolefin resin layer configuring the innermost layer, and a second polyolefin resin layer arranged outside of the first polyolefin resin layer; the amount of calcium leaching, measured in accordance with SEMI F-57, of the material of the first polyolefin resin layer is less than 30 &#x3bc;g/m2; the ratio of the thickness of the first polyolefin resin layer to the total thickness of the first polyolefin resin layer and the second polyolefin resin layer is 0.011-0.17. By means of this configuration, it is possible to suppress the amount of leaching of calcium and organic substances to a low level, and to realize a pipe having a strength that takes into account a 60&#xb0; C. use environment.

Growing community of inventors

Kyoto, Japan

Kouzou Makino