David H. Graef

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Spring Grove, IL, US

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Patents Grantslast 30 patents

Information Patent Grant
Plug valve assembly
- Patent number 11,732,814
- Issue date Aug 22, 2023
- SPM Oil & Gas Inc.
- James D. McPhail
- F16 - ENGINEERING ELEMENTS AND UNITS GENERAL MEASURES FOR PRODUCING AND MAINT...

Patents Applicationslast 30 patents

Information Patent Application
Plug Valve Assembly
- Publication number 20230119815
- Publication date Apr 20, 2023
- SPM OIL & GAS INC.
- James D. McPhail
- E21 - EARTH DRILLING MINING