Method and apparatus to detect gas influx using mud pulse acoustic signals in a wellbore
US11098577B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 4, 2019 |
| Grant date | Aug 24, 2021 |
| Priority date | — |
| Expiry date | Jul 31, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/2636
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for determining a gas influx into a wellbore. A work string defining an inner bore area and an annulus area, with a pair of inner bore sensors in the inner bore and a pair of annulus sensors in the annulus. A processor sets a gas influx alarm limit based on a steady-state value of an acoustic parameter measured by the pair of inner bore sensors in an absence of a gas influx and a steady-state value of the acoustic parameter measured by the annulus sensors in the absence of the gas influx. The processor determines a gas influx in the wellbore when a subsequent value of the acoustic parameter is outside of the alarm limit and performs an action at the work string to counteract the gas influx in the wellbore.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.