Abstract: The electrofusion joint includes a tubular main body, a stopper portion, a first heat generating section, and a second heat generating section. The tubular main body includes a joint receiving portion. The stopper portion projects inward on the inner surface of the main body. The first heat generating section includes a heating wire wound and arranged at the joint receiving portion. The second heat generating section includes a heating wire wound so that wound parts are adjacent to each other and the heating wire is disposed in the stopper portion. The first heat generating section includes at least one heat generating portion in which the heating wire is wound so that the wound parts are adjacent to each other.

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

Abstract: Provided is piping for ultra-pure water from which the amount of calcium leaching can be suppressed to an extent that satisfies the quality required for ultra-pure water, and which can be produced so as to be provided with mechanical properties. [Solution] This piping for ultra-pure water is used for conveying ultra-pure water and includes a first polyolefin-based resin layer constituting the innermost layer, and a second polyolefin-based resin layer disposed on the outer side of the first polyolefin-based resin layer, wherein the calcium concentration within the first polyolefin-based resin layer is 10 ppm or lower, and the calcium concentration within the second polyolefin-based resin layer is between 20 ppm and 200 ppm inclusive. With this constitution, the amount of calcium leaching can be suppressed to an extent that satisfies the quality required for ultra-pure water, and the piping can be produced so as to be provided with mechanical properties.

Abstract: Provided is a leakage detector which is capable of exhibiting high sensitivity to vibration-sounds caused by water leakage from a synthetic resin pipe and thus setting an installation span longer to thereby make it possible to more efficiently perform a water leakage inspection for a synthetic resin pipe. The leakage detector (6) comprises a base (21), a piezoelectric element (9) supported by the base (21) and configured to convert vibration-sounds to an electric signal, and a weight member (28) loaded against the piezoelectric element (9). The piezoelectric element (9) is made of a polymeric piezoelectric material. One end of the piezoelectric element (9) is supported by an upper end of a support post (27), and the weight member (28) is loaded against the other end of the piezoelectric element (9).

Abstract: Provided is a leakage detector which is capable of exhibiting high sensitivity to vibration-sounds caused by water leakage from a synthetic resin pipe and thus setting an installation span longer to thereby make it possible to more efficiently perform a water leakage inspection for a synthetic resin pipe. The leakage detector (6) comprises a base (21), a piezoelectric element (9) supported by the base (21) and configured to convert vibration-sounds to an electric signal, and a weight member (28) loaded against the piezoelectric element (9). The piezoelectric element (9) is made of a polymeric piezoelectric material. One end of the piezoelectric element (9) is supported by an upper end of a support post (27), and the weight member (28) is loaded against the other end of the piezoelectric element (9).

Abstract: An improved armature construction in which a coil winding wiring board and cooperating insulator around which the coils are wound at least in part wherein the insulator and wiring board are interconnected by an attachment arrangement that automatically positions and retained components in the desired circumferential, axial and radial positions.

Abstract: An improved armature construction in which a coil winding wiring board and cooperating insulator around which the coils are wound at least in part wherein the insulator and wiring board are interconnected by an attachment arrangement that automatically positions and retained components in the desired circumferential, axial and radial positions.