| 摘要 |
<p>1,042,275. Welding by pressure; making heat exchangers. ASSOCIATED ELECTRICAL INDUSTRIES Ltd. April 20, 1964 [July 19, 1963], No. 28735/63. Headings B3A and B3R. [Also in Divisions B5 and F2] In friction welding first and second members a third member is inserted therebetween and rotated relative thereto to heat the mating surfaces of the three members to welding temperature, the rotation is stopped and increased force is applied to complete two welds. A tubular stub 3, Fig. 1 (not shown), is formed on a heat exchanger tube plate 1, a cylindrical member 11 having an annular flange is inserted into the stub and a splined mandrel 15 is engaged with grooves in the member 11. The mandrel is rotated by an electric motor and a tube 7 and stub 3 are pressed towards each other to frictionally engage the member 11 and when welding temperature is reached the mandrel is stopped and the force pressing the tube is increased to effect two welds. The cylindrical part of the member 11 may be removed by reaming, may be left in position or may be omitted. The member 11 may be a tube long enough to be rotated from the outside. Metals, plastics or ceramics may be welded and hydraulic or pneumatic rams may provide the welding forces.</p> |
