Select fire well perforator system and method of operation
US4656944A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 6, 1985 |
| Grant date | Apr 14, 1987 |
| Priority date | — |
| Expiry date | Dec 6, 2005 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF42D1/06
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A well perforator system and method employs an electromagnetic wave frequency receiver, one for each of at least two gun intervals, that receives a transmitted signal conveyed through well tubing from the earth's surface. The signal is converted to an electrical pulse which detonates a blasting cap and fires the gun perforators. Each gun interval is a separate system with different activating frequencies and each is separately activated to assure that all the intervals are fired. A timer may be used to activate the electromagnetic wave receiver after the gun is in the well to prevent accidental surface firing of the guns from stray sources of electromagnetic waves. Once in the well, only the transmitted pulses are able to detonate the guns. Once the last interval is fired, a wave frequency-activated gun above the uppermost gun interval is detonated with circulation shots to penetrate only the tubing. This creates an instant, intense pressure drop across the perforations to help in cleanup. Once the pressure equalizes, a casing cutter can be lowered down the well to cut the guns off and have them dropped to bottom. A microphone may be positioned at the earth's surface to detect firi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.