Drilling head
US4293047A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 24, 1979 |
| Grant date | Oct 6, 1981 |
| Priority date | — |
| Expiry date | Aug 24, 1999 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B33/085
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A drilling head includes a tubular body with top, bottom and side openings. An oriented side outlet with an oriented replaceable bushing is releasably connected to the side opening. The head without the side outlet will pass through most rotary tables. A top closure closes the annulus between a portion of the head above the side opening and a drive tube such as a kelly extending through the head. The top closure includes a rotor, adapted to form a non-rotating seal with the kelly, and a stator, with a rotating seal between the stator and rotor. The stator is supported on and releasably connected to the body. The rotor includes a seal tube rotatably supported by inboard bearings on the stator located above the rotating seal. The top closure is small enough to pass through even rotary tables that are too small to pass the drilling head.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.