Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4842074 | Gas storage well safety system and method | Michael J. Bednarz, Ronald K. Churchman | 1989-06-27 |
| 4834183 | Surface controlled subsurface safety valve | Michael B. Vinzant, Rennie L. Dickson, Robert C. Hammett | 1989-05-30 |