Well casing perforator
US4106561A · kind A · utility
Inventors
Key dates
| Filing date | May 12, 1977 |
| Grant date | Aug 15, 1978 |
| Priority date | — |
| Expiry date | May 12, 1997 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B29/00
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A well casing perforator adapted to be used with pneumatically powered rotary drilling equipment. It includes an upright elongated body which is inserted within the casing. The body is attached to the lower end of a drill rod which imparts vertical or angular movement to the elongated body while within the casing. The body is guided axially within the casing by rollers which engage the interior casing wall. A rotatable wheel has teeth capable of penetrating the casing wall as the wheel rolls in engagement with the casing. The wheel is mounted at the outer end of a carrier pivoted to the elongated body about a horizontal axis. The carrier in turn is controlled by a piston assembly subject to pneumatic pressure within the drill rod. The piston assembly is pivotally connected to the carrier to move it from a first position at which the wheel is retracted from engagement with the casing to a second position at which the wheel engages the interior wall of the casing. Upon subsequent downward movement of the body, the wheel and carrier are moved to a third position at which the wheel teeth penetrate the casing as the wheel rolls with its teeth in engagement through the casing. Upward mov…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.