Self-contained downhole gauge system
US4866607A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 6, 1985 |
| Grant date | Sep 12, 1989 |
| Priority date | — |
| Expiry date | May 6, 2005 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/12
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
In an oil well instrumentation system, the downhole sensor system is controlled by a computer which is powered-on only during sampling movement. An independent circuit, continuously powered, detects significant sensor rate-of-change values whereby the computer-sampling equipment is powered-on. A self-contained memory gauge includes either semiconductor or magnetic core memory for retaining downhole information related to sampled parameters, such as borehole temperature and pressure. A microprocessor-based computer manages the power utilization by independently and selectably energizing and deenergizing different sections of the gauge. The magnetic core memory is tested for operability, and the addressing of the magnetic core memory is adjusted in accordance with any inoperable memory locations. Samples of the monitored environmental conditions can be taken at variable rates dependent upon software monitoring of the condition, the remaining battery life and the remaining memory capacity and in response to hardware monitored pressure changes. Each sample can be taken to a selectable resolution. A watchdog circuit monitors the microprocessor to insure that it is operating within a pre…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.