Method and apparatus for driving pipe
US4232752A · kind A · utility
14Cited by
11References
29Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 20, 1978 |
| Grant date | Nov 11, 1980 |
| Priority date | — |
| Expiry date | Mar 20, 1998 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B6/00
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A casing hammer for driving casing while drilling a water well comprises a housing having an annular pneumatic chamber with a relatively lightweight, short-stroke annular piston. The piston is reciprocably driven at a high rate to provide a large number of light blows of controllable energy upon an annular anvil that seals one end of the chamber. Percussive blows upon the anvil are transmitted through a drive head and adapter to the upper end of the pipe to be driven. The hammer is suspended from a rotary drive head that operates a hollow drill string extending downwardly through the hammer and through the casing driven thereby.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.