Drill pipe assemblies
US4997048A · kind A · utility
Inventor
Key dates
| Filing date | May 7, 1990 |
| Grant date | Mar 5, 1991 |
| Priority date | — |
| Expiry date | May 7, 2010 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B17/22
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An improved drill pipe assembly that is formed as a concentric walled pipe having both an axial and an annular space therethrough, and the pipe section includes means for selectively communicating the adjoining annular spaces through the series of respective box end/pin end joints whereby equipment compartmentation, conductor traverse, ballast containment, gas pressurization and weight addition can be effectively utilized in controlled manner. The pipe is assembled by threaded engagement of the pin end joint to each of an outer pipe and an inner pipe, and subsequent threaded joinder of the concentric pipes to a box end joint while also utilizing an intermediate double-threaded sleeve between the inner pipe threads and the box end collar threads.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.