Method of monitoring and controlling a well pump apparatus
US5284422A · kind A · utility
Inventors
Key dates
| Filing date | Oct 19, 1992 |
| Grant date | Feb 8, 1994 |
| Priority date | — |
| Expiry date | Oct 19, 2012 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B2203/0201
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A method of monitoring and controlling a well pump apparatus having an electric motor that rotates a crank arm having a counterweight thereon, a pivoted walking beam oscillated by the crank arm which reciprocates a sucker rod and a pump between an upstroke and a downstroke. The electric current from the motor is measured periodically between the peak upstroke motor current and the peak downstroke motor current, and the results are then integrated to deduce an analysis current per stroke. The mean of a number of sequential samples of the analysis current per period is calculated and thereafter the standard deviation is calculated. The last sample will be within two standard deviations of the mean or the results will be discarded and new data gathered. The well pump apparatus is stopped if a selected number of consecutive samples fall below a preselected threshold.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.