Rotary drilling head
US4416340A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 24, 1981 |
| Grant date | Nov 22, 1983 |
| Priority date | — |
| Expiry date | Dec 24, 2001 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B33/085
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
In accordance with the present invention, the drilling head includes a body or spool having a flow bore and a removable side outlet. Upon removal of the side outlet, the drilling head will pass through most rotary tables. The drilling head further includes a closure member for closing the annulus between that portion of the drilling head above the side outlet and a drive tube, such as a kelly, extending through the drilling head flow bore. The closure member includes a nonrotating support tube and a rotating seal tube adapted to form a nonrotating seal with the drive tube. The seal tube is rotatably supported by bearings within the support tube. The closure member is small enough to pass through even rotary tables that are too small to pass the drilling head. A segmented clamp secures the closure member to the drilling head body around one end of the flow bore. The clamp includes at least two segments, for fast actuation, having one end connected to a variable length linkage. The variable length linkage includes a nut pivotally connected to one segment, a screw engaging the nut, and a pivotal connection connecting the screw to another segment. The segmented clamp is tightened and r…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.