| 摘要 |
557,280. Making steel bottles &c. GORDON, S. H. Sept. 10, 1942, No. 12796. [Classes 83 (ii) and 83 (iv)] A hollow metal article of spherical form, such as a steel bottle for containing compressed gases, is made by forming two hemispherical shells with a rim b of thickness greater than the rest of the shell and extending at c beyond the medium plane of the finished article, and welding the two shells by electric resistance flash welding, the portions extending beyond the medium plane being burned away during the welding operation. The excess thickness may be produced by upsetting or turning internally as shown, or externally or both, a blank of initial thickness at all points the same as the desired thickness of the rim. |
