Recirculatable ball-drop release device for lateral oilwell drilling applications
US6318470A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 2000 |
| Grant date | Nov 20, 2001 |
| Priority date | — |
| Expiry date | Feb 15, 2020 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B23/0413
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method for disconnecting tubular members and a ball-drop release device including an upper housing connected to tubing and a lower housing connected to a bottom hole assembly. The upper housing includes a recess end having grooves, and the lower housing includes an extension end having splines that fit into the upper housing grooves. The splined connection is designed to resist drilling motor backup torque and prevent the release mechanism from locking up. In the pre-release position, a ball sleeve is disposed within the extension and held in place by shear screws. To actuate the device, a ball, preferably having a density equal to the density of the drilling fluid, is dropped into the well and pumped to engage the ball sleeve. The ball seats with the ball sleeve whether the well bore is disposed vertically, laterally, or sloped upwardly. Once the ball seats, pressure builds behind the sleeve until the shear screws shear. The ball sleeve moves into a recess in the lower housing thereby making the upper and lower housings separable. Before disconnecting the upper and lower housings, fluid flows into the well through recirculation ports on the lower end of the ball sleeve. After se…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.