Abstract: The improved electrofusion joint and header for supplying hot water that perform satisfactorily at elevated temperatures as evidenced by high heat resistance, that exhibit good sealing property and that can be handled efficiently in mounting and various other operations have a crosslinked thermoplastic resin layer and at least one joining portion which comprises a non-crosslinked thermoplastic resin layer that is formed a as an integral part of said crosslinked thermoplastic resin layer in the area where it contacts a tubular member to be joined, and a heating electric wire provided either within or on the outer or inner surface of said non-crosslinked thermoplastic resin layer. Such electrofusion joint and header are applicable to any part of a piping system for supplying hot water and they will withstand use for a prolonged period.

Abstract: The improved electrofusion joint and header for supplying hot water that perform satisfactorily at elevated temperatures as evidenced by high heat resistance, that exhibit good sealing property and that can be handled efficiently in mounting and various other operations have a crosslinked thermoplastic resin layer and at least one joining portion which comprises a non-crosslinked thermoplastic resin layer that is formed a as an integral part of the crosslinked thermoplastic resin layer in the area where it contacts a tubular member to be joined, and a heating electric wire provided either within or on the outer or inner surface of the non-crosslinked thermoplastic resin layer. Such electrofusion joint and header are applicable to any part of a piping system for supplying hot water and they will withstand use for a prolonged period.

Abstract: The improved electrofusion joint and header for supplying hot water that perform satisfactorily at elevated temperatures as evidenced by high heat resistance, that exhibit good sealing property and that can be handled efficiently in mounting and various other operations have a crosslinked thermoplastic resin layer and at least one joining portion which comprises a non-crosslinked thermoplastic resin layer that is formed a as an integral part of said crosslinked thermoplastic resin layer in the area where it contacts a tubular member to be joined, and a heating electric wire provided either within or on the outer or inner surface of said non-crosslinked thermoplastic resin layer. Such electrofusion joint and header are applicable to any part of a piping system for supplying hot water and they will withstand use for a prolonged period.

Abstract: There is disclosed a device for driving four wheels of a car at all times. In this device, a differential is provided between the left front wheel shaft and right rear wheel shaft and likewise a differential is also provided between the right front wheel shaft and left rear wheel shaft so that said two differentials can be driven by the same driving source.

Abstract: A pipe element for a heat exchanger which comprises at least one bent portion and at least two linear portions connected to the bent portion wherein an angle formed by the adjacent two linear portion is in a range of from about 30' to 3.degree..

Abstract: The invention provides flat, thin and hollow heat exchanger units of synthetic resin make, each operating to have a cooling water fed thereto and air flowed horizontally in an air passage therebetween, thus realizing an indirect contact heat exchange between the air and the cooling water through both wall plates. The invention further relates to a crossflow cooling tower incorporating a wet heat exchanger or packing material and an indirect contact type heat exchanger operating on the afore-mentioned heat exchanger units.

Abstract: The heat exchanger has a zig-zagged liquid-flowing passage and an overflowed-liquid escaping conduit. When an excessive amount of cooling water is supplied to the heat exchanger, a part of cooling water flows into the overflowed-liquid escaping conduit through a dam formed between the liquid-flowing passage and the escaping conduit. The heat exchanger is formed by assembling a plurality of heat exchanging partition plates formed by molding. The heat exchanging partition plates have the same shape and the same dimensions, and they are easily engageable with and detachable from each other.

Abstract: A counter-flow square type cooling tower is provided with a sprinkler. The sprinkler has four horizontally extending sprinkler pipes. A plurality of water spraying openings are formed along the axial direction of each of the sprinkler pipes to spray cooling water downwardly, and at least one spraying opening is formed at the free end of each of the sprinkler pipes to spray the cooling water outwardly.

Abstract: A heat exchanger comprises a plurality of coil units to form a substantially rectangular prism. Each of the coil units is supported by a pair of supporting frame members through a pair of electrically insulating spacers without direct contact with the supporting frame members.