Beam pump dynamic load monitoring and methods

1. A dynamic load monitoring system for a motor driven walking beam and cable harness actuated polished rod coupled in driving relationship with a down hole pump, comprising:

a monitoring device configured for attachment to the cable harness of such pump at a location above the polished rod effective to avoid monitoring error induced by thermal influence from the polished rod,

the monitoring device having:

a strain gauge configured to be stressed in tension to measure dynamic loading of at least one cable of the cable harness as the pump operates; and

a wireless transmitter configured to transmit the dynamic loading measurement; and

an external device configured to receive the transmitted dynamic loading measurement.

2. The system of claim 1 , wherein the external device comprises a monitoring location.

3. The system of claim 1 , wherein the external device comprises a motor controller configured to adjust a pumping frequency of the pump in relation to the dynamic loading measurement.

4. The system of claim 1 , wherein the monitoring device further comprises a solar cell configured to power the device.

5. The system of claim 1 , wherein the monitoring device further comprises a battery configured to power the device.

6. The system of claim 1 , wherein the monitoring device is configured for attachment between two cables of the cable harness at an attachment point at said location above the polished rod, such two cables being drawn together an amount effective to derive a tensile stress across the strain gauge representing a generally horizontal restoring force, tending to separate the cables from one another at the attachment point as the cables are tensioned in a generally vertical direction.

7. A monitoring device, comprising:

means for attaching the device to an attachment point of a cable harness of a walking beam pump such device being configured with a threaded member to engage and draw two cables of the cable harness together to derive a tension force to measure a generally horizontal restoring force tending to separate such cables from one another at the attachment point as the cables are tensioned in a generally vertical direction;

means including a strain gauge responsive in tension to said tension force for measuring dynamic loading of at least one cable of the cable harness as the pump operates;

means for powering the measuring means; and

means for transmitting the dynamic loading measurement to a different location.

8. The monitoring device of claim 7 , wherein the powering means comprises a solar cell.

9. The monitoring device of claim 7 , wherein the powering means comprises a battery.

10. The monitoring device of claim 7 , wherein the transmitting means comprises a wireless transmitter.

11. The monitoring device of claim 7 , wherein the different location comprises a location proximate to a motor controller of the pump.

12. A method of monitoring dynamic loading in a walking beam pump, comprising:

attaching a monitoring device including a strain gauge to an attachment point of a cable harness connecting a polished rod to the pump, such attachment being made at a location above the polished rod effective to avoid monitoring error induced by thermal influence from the polished rod;

measuring the tensile stress in at least one cable of the cable harness induced at the attachment point by operation of the pump by stressing the strain gauge in tension; and

transmitting the measurement to a different location.

13. The method of claim 12 , wherein attaching a monitoring device to an attachment point of a cable harness comprises attaching the device to two cables of the cable harness, whereby the device is positioned to measure a horizontal restoring force tending to separate the cables from one another at the attachment point as the cables are tensioned in a generally vertical direction.

14. The method of claim 12 , wherein attaching a monitoring device to an attachment point of a cable harness comprises attaching the device to a single cable of the cable harness.

15. The method of claim 12 , wherein the different location comprises a location proximate to a motor controller of the pump, the method further comprising using the measurement to adjust a pumping frequency of the pump.