IP Library › Granted Patent US 5,111,885
Granted Patent Utility
US 5,111,885 · App. 07/598,932

Decentralized casing hole puncher

Inventor: Donald V. Umphries
Patented Case View Patent ↗
Granted: May 12, 1992 Filed: Oct 17, 1990
Inventor
Donald V. Umphries
Assignee (at issue)
Directional Wireline Services, Inc.

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Quick Facts
Patent No.
US 5,111,885
App. No.
07/598,932
Filed
1990-10-17
Granted
1992-05-12
Kind
A