IP Library Granted Patent US 4,916,281
Granted Patent Utility
US 4,916,281 · App. 07/313,824

Gas back-purging during welding of pipe

Inventors: Lee M. Flasche, Gregory L. Hoback, James L. Meyers
Patented Case View Patent ↗
Granted: Apr 10, 1990 Filed: Feb 23, 1989
Inventors
Lee M. Flasche
Gregory L. Hoback
James L. Meyers
Assignee (at issue)
Haynes International, Inc.

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Quick Facts
Patent No.
US 4,916,281
App. No.
07/313,824
Filed
1989-02-23
Granted
1990-04-10
Kind
A