PUMP-OFF CONTROLLER

• US 3,559,731 A
• Filed: 08/28/1969
• Issued: 02/02/1971
• Est. Priority Date: 08/28/1969
• Status: Expired due to Term

• Current Assignee: Jerry I. Stafford
• Original Assignee: Jerry I. Stafford
• Inventors: Stafford, Jerry I.
• Application Number:
  US04/853,900
• Time in Patent Office: 523 Days
• US Class Current: 166/53
• CPC Class Codes: E21B 47/009 Monitoring of walking-beam pump systems
• CPC Class Codes: H02P 29/40 Regulating or controlling the amount of current drawn or delivered by the motor for controlling the mechanical load

Abstract

To obtain optimum production from a producing oil well in which the pump rate exceeds flow rate of liquid into the well, it is necessary to determine the most effective producing cycle of the well. During the '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' cycle the well must be pumped enough to obtain the maximum amount of well fluid. During the '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' cycle the fluid permeating through the formation rocks refills the well bore. The controller disclosed here is designed to stop the pump, preventing rod wear and expending excessive mechanical energy, when the fluid has been pumped from the well. The well pump is restarted only after a predetermined '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' time. It is a shortcycle controller of minimum cost, simple in operation, and easy to maintain. Wide flexibility in timing permits adjustment of the off and on cycles for best results.

Claims

1. Apparatus for controlling the motor of a pump adapted to pump liquid from a well at a rate greater than that at which said liquid flows into said well comprising:

a source of electric power;

a first resettable timer having a normally open set of contacts (1), which close at an adjustable time after energization of said timer;

a flow-sensitive switch mounted in the flowline from said well having a set of contacts (2) opened by flow of liquid through said line and closed when said flow is negligible;

a second resettable timer having a normally open set of contacts (3) in parallel with said contacts (1) and two sets of normally closed contacts (4) and (5), one of said two sets of contacts (4) being in series in the starting apparatus of said pump and the other of said two sets of contacts (5) being in series with said contacts (2) and said first resettable timer across said source of power, said second timer being adapted to actuate its sets of contacts at an adjustable time after energization of said second timer, said second timer being connected through said contacts (1) and said contacts (3) across said source of power; and

A time-delay relay connected in parallel with said second timer and having a set of normally closed contacts (6) connected in series with said first timer and said contacts (2) and said contacts (5) across said source of power.

2. Apparatus in accordance with claim 1 in which the maximum time to which said first timer can be adjusted is about 30 seconds, the maximum time to which said second timer can be adjusted is about 150 minutes, and the actuation time of said time-delay relay is of the order of 1 minutes.