| 摘要 |
A method of manufacturing a corrugated metallic pipe, including inserting into a smooth cylindrical metallic pipe a first mandrel having an axially extending corrugation having a predetermined shape and height, and radially expanding the first mandrel against cheek means, which surrounds the pipe and has a corrugation at least approximately corresponding to the corrugation of the first mandrel, to provide a first preformed corrugation on the metallic pipe, thereafter, inserting into the pipe with the first preformed corrugation, a second mandrel having an outer diameter corresponding to an inner diameter of the first corrugation, thereafter, radially displacing into corrugation hollows disc-shaped, axially spaced from each other, jaws which surround the pipe with the first preformed corrugation, and axially displacing the jaws toward each other, effecting folding up of the first preformed corrugation to obtain a final predetermined corrugation of the pipe.
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