Drilling head
US4285406A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 24, 1979 |
| Grant date | Aug 25, 1981 |
| Priority date | — |
| Expiry date | Aug 24, 1999 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B3/04
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A drilling head includes a tubular body with top, bottom and side openings. 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 seal tube has a replaceable rubber stripper to seal with the kelly. An upwardly flaring medial flange on the stripper guides upwardly flowing annulus fluid toward the side opening and away from the rotating seal. The rotor includes an elastomer sandwich drive bushing, rising above the stator into the rotary table, splined to the seal tube and secured to the kelly by slips. A segmented clamp securing the top closure to the body includes more than two segments, for fast actuation, and the segments are guided so that but one motor is required to operate all segments. The segmented clamp securing the top closure stator to the drilling …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.