| 摘要 |
<p>913,279. Shaft couplings. REYNOLDS METALS CO., and REED ROLLER BIT CO. April 14, 1961 [May 16, 1960], No. 13596/61. Class 80 (2). [Also in Groups XXII and XXVIII] A drill pipe coupling comprises a non-ferrous metal or alloy pipe 4 having a screwthreaded, thickened end portion and a work-hardened land 8, and a steel tool joint member 2 screwed and shrunk on to the pipe, that member having an internal land 7 complemental to the land 8 which has a diameter slightly greater than that of the land 7 when the pipe and member are both at the same temperature. As shown, the screw-threads 5, 6 of the member and pipe are tapered, and the smooth-finished end 15 of the pipe forms a seal with a radial shoulder 13 of the member.</p> |
