Jarring method and apparatus using fluid pressure to reset jar
US8365818B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 2012 |
| Grant date | Feb 5, 2013 |
| Priority date | — |
| Expiry date | May 15, 2032 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B31/1135
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method and apparatus for delivering repetitive jarring impacts to a stuck object downhole. The jarring tool is deployed on coiled tubing or other tubular well conduit, and fluid pressure is used to cycle the jar without reciprocating the well conduit at the wellhead. A hydraulic reset assembly is included. The hydraulic chamber is in fluid communication with the flow path through the tool. Thus, when the internal fluid pressure inside the tool exceeds the external pressure in the well, the fluid pressure drives the piston in the hydraulic chamber to urge the tool toward the contracted position. In this way, the reset assembly can overcome the tendency of fluid pressure to extend the tool. The reset assembly can be configured to equalize the extension pressure, to prevent undesired cocking of the tool, or to overcome the extension pressure to contract the tool for recocking the jar mechanism.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.