Shock isolation sub for use with downhole explosive actuated tools
US5188191A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 9, 1991 |
| Grant date | Feb 23, 1993 |
| Priority date | — |
| Expiry date | Dec 9, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16F1/40
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The present disclosure is directed to a shock absorbing device for threading in a tubing string for running delicate instruments into a well borehole where they are in near proximity to explosives which might otherwise be detonate. This particularly is important in a well borehole which is filled with a standing column of liquid which transmits the shock waves quite readily. This is a separate assembly which can be threaded in the tubing string and has a pin and box connection for that. Moreover, it is formed of an outer mandrel surrounding connected inner upper and inner lower mandrels; the inner mandrels define annular spaces for receiving shock absorbers defined by alternating thin layers of metal and rubber; the metal and rubber washers have different shock wave impedances and tend therefore to absorb shock waves traveling either upwardly or downwardly in the well borehole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.