Randy Johnston

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Spring, TX, US

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Patents Grantslast 30 patents

Information Patent Grant
Composite seal for rotary cone rock bits
- Patent number RE36452
- Issue date Dec 21, 1999
- Smith International, Inc.
- Robert G. Upton
- 277 - Seal for a joint or juncture
Information Patent Grant
Composite seal for rotary cone rock bits
- Patent number 5,362,073
- Issue date Nov 8, 1994
- Smith International, Inc.
- Robert G. Upton
- E21 - EARTH DRILLING MINING