Automatic data retrieval system for pumping wells

Claim 1

A well monitoring system for measuring operating conditions at a plurality of pumping wells of the type having a crank shaft and a sucker rod string and means to reciprocate the sucker rod string to operate a downhole pump as the crank shaft revolves, comprising: a. at least two transducers connected to each of said pumping wells, a first transducer generating a load signal representative of the changing load conditions on the sucker rod string during pumping and a second transducer generating a timing pulse at least once during each pumping stroke of the sucker rod string representative of the rate of rotation of said crank shaft, b. a central computer for generating a plurality of monitor commands, each monitor command identifying a selected one of said pumping wells, and a retrieval command, and c. a remote terminal unit coupled to said transducers and to said central computer, comprising: 1. a frequency-to-digital converter, 2. a digital storage unit connected to the output of said frequency-to-digital converter, 3. means responsive to each of said monitor commands for selectively connecting the first transducer at the pumping well identified by a monitor command to said frequency-todigital converter and the second transducer at the same pumping well to said digital storage unit, whereby the load signal from the selected pumping well is converted to a digital signal by the frequency-to-digital converter and whereby the timing signal from the selected pumping well enables the digital storage unit to store the digital signal from the frequency-to-digital converter at a data rate dependent upon the rate of rotation of the crank shaft of the selected pumping well, and 4. means responsive to said retrieval command from the computer for enabling the digital signals to be clocked out of the digital storage unit into said computer at a data rate that is independent of the rates of rotation of the crank shafts of the pumping wells.

Claim 13

A method of measuring operating conditions at a plurality of pumping wells of the type having a crank shaft and a sucker rod string and means to reciprocate the sucker rod string to operate a downhole pump as the crank shaft revolves, comprising the steps of: a. generating a load signal representative of the changing load conditions on the sucker rod string of each well during pumping, b. generating a timing pulse at least once during each pumping stroke of the sucker rod string of each well representative of the rate of rotation of the crank shaft, c. generating a plurality of monitor commands, each monitor command identifying a selected one of said pumping wells, d. converting the load signal from the pumping well identified by the monitor command to a digital signal, and e. storing said digital signal in a digital storage unit at the data rate of said timing pulses from the identified pumping well.

Claim 14

A method of measuring operating conditions at a plurality of pumping wells of the type having a crank shaft and a sucker rod string and means to reciprocate the sucker rod string to operate a downhole pump as the crank shaft revolves, comprising the steps of: a. generating a load signal representative of the changing load conditions on the sucker rod string of each well during pumping, b. generating a timing pulse at least once during each pumping stroke of the sucker rod string of each well representative of the rate of rotation of the crank shaft, c. generating a plurality of monitor commands, each monitor command identifying a selected one of said pumping wells, d. converting the load signal from the pumping well identified by the monitor command to a digital signal, and e. storing said digital signal in a digital storage unit at the data rate of said timing pulses from the identified pumping well.