Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5931232 | Mechanical connection between base pipe and screen and method for use of the same | Ralph H. Echols, James D. Hendrickson | 1999-08-03 |
| 5842522 | Mechanical connection between base pipe and screen and method for use of the same | Ralph H. Echols, James D. Hendrickson | 1998-12-01 |
| 5803179 | Screened well drainage pipe structure with sealed, variable length labyrinth inlet flow control apparatus | Ralph H. Echols, Syed Hamid, David Fish, Timothy Edward Harms | 1998-09-08 |