PIPE OR PIPE FITTING AND METHOD FOR MANUFACTURING THE SAM

摘要

1499390 Pipes; pipe fittings MITSUI MINING & SMELTING CO Ltd and MITSUI KINZOKU ENG SERVICE CO Ltd 30 Sept 1975 [4 Oct 1974 (2)] 39997/75 Headings F2P and F2G A pipe or pipe fitting comprises a sintered hollow cylindrical core member made of a ceramic material, and an outer sheath mounted on the core member and made of an easily machinable material having a high mechanical strength. The core 24 of Fig. 1 is obtained by shaping in a viscous state a ceramic material including a silicon carbide refractory material with a bonding agent such as silicon nitride or silicate, followed by sintering. Outer sheath 26 is a thermoplastic synthetic resin such as polyvinyl chloride, polyethylene and other reinforced plastics materials which have a greater coefficient of thermal expansion than metal. The outer sheath has an inner diameter smaller than the outer diameter of the core diameter. It is placed over the core after first being heated. The embodiment of Fig. 5 has a metallic sheath 126 of cast iron and comprises a pair of sheath halves 127. The halves may be bolted together or welded together along the seams between the halves. There is an elastic layer 38 between the sheath and the core. The same arrangements can be applied to a straight pipe.