Bobby E Douglas

US Patent:

39389103, Feb 17, 1976

Filed:

Nov 1, 1974

Appl. No.:

5/519904

Inventors:

Bobby L. Douglas - Garland TX

Assignee:

Dresser Industries, Inc. - Dallas TX

International Classification:

F04B 4900

US Classification:

417 12

Abstract:

Various functions of a production oil well are monitored to cause a switch closure for each normal cycle of the pump. Alternatively, the level of the fluid within the well is monitored to cause the switch closure. The switch closure activates a first oscillator whose count is compared with a variable frequency oscillator over a given period of time to ascertain the percentage of time of normal operation. The integrated time is adjusted to shut down the system when the percentage of time drops to or below the preselected amount. In response to the integration timer signal, a shutdown timer is turned on which restarts the cycle after a preselected amount of time. When the system is restarted by the shutdown timer, a pump-up timer is turned on which is adjusted to allow for a desired pump-up time. As the pump-up timer is allowing the system to recycle, the integration timer is reset and the recycling is completed if the requirements of the integration timer are met. Otherwise, the unit is shut down again and the system recycled.

US Patent:

39362310, Feb 3, 1976

Filed:

Nov 5, 1974

Appl. No.:

5/520993

Inventors:

Bobby L. Douglas - Garland TX

Assignee:

Dresser Industries, Inc. - Dallas TX

International Classification:

F04B 4900

US Classification:

417 12

Abstract:

A sensor associated with the production of an oil well generates a signal indicative of pumpable fluid available in the wellbore. The signal activates a first oscillator whose count is compared with a variable frequency oscillator having a frequency of approximately one-half that of the first oscillator. The comparison is made over a given period of time to ascertain the percentage of time the well has produced fluid. The integrated timer is adjusted to shut down the system when the percentage of time the valve is open drops to the preselected amount. In response to the integration timer producing a signal, a shutdown timer is turned on which restarts the cycle after a preselected amount of time. The length of shutdown time for the pumping unit is preset according to the well fill-in rate. When the system is restarted by the shutdown timer, a pump-up timer is turned on which is adjusted to allow for a desired pump-up time.