Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5794699 | Metal-to-metal sliding side door for wells | Robert C. Hammett, William R. Welch, Ronald K. Churchman | 1998-08-18 |
| 4624310 | Well apparatus | Ralph H. Echols, James B. Renfroe, Jr. | 1986-11-25 |