Methods and apparatus for producing corrugated metal tubes
Abstract
Abstract THE PRESENT INVENTION RELATES TO METHODS AND APPARATUS FOR PRODUCING CORRUGATIONS IN METALLIC TUBES AND IS CHARACTERIZED BY THE FACT THAT IT IS POSSIBLE TO PRODUCE CORRUGATIONS OF VARIOUS SHAPES BY UTILIZING AT LEAST TWO CORRUGATING RINGS OR TWO SETS OF CORRUGATING ROLLS. IN PARTICULAR THE INVENTION RELATES TO METHODS AND APPARATUS CAPABLE OF PRODUCING EASILY CORRUGATIONS OF GREATER DEPTH AS COMPARED WITH PITCH, CORRUGATIONS OF A SMALL PITCH WHOSE TROUGH IS WIDER THAN THE CREST (TUBES WITH SUCH CORRUGATIONS HAVE GOOD BENDING CHARACTERISTICS AND OTHER MECHANICAL PROPERTIES AND PERMIT A CABLE TO BE PULLED INTO THEM MORE EASILY), AND FURTHERMORE CORRUGATIONS CONFORMABLE TO THE SHAPES OF APEXES OF CORRUGATING RINGS OR ROLLS, WITHOUT EMPLOYING ANY CORE (CORRUGATING TOOL TO BE APPLIED INSIDE THE TUBE) AS IN THE CONVENTIONAL APPARATUS.
Inventors
- 👤 Susumu Tobita
Bibliographic Details
Claims Analysis
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| 3.5 Years (Year 4) | 1974-03-08 | 1974-09-07 | 1975-03-09 | $2000.00 | Window Closed / Lapsed |
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