Structural Analysis And Safety Study On Offset Screw Pump Driving Device

Screw pump is one of the most common mechanical oil production device, theconventional screw pump and direct drive screw pump is mainly used in oil field at presentstage. How to increase drive efficiency and prevent the rod string reversal is always problemsto be solved. The conventional screw pump generally uses the belt and bevel geartransmission mechanism, transmission loss of rotation, inefficiently and big loss, because ofthe belt transmission is easy to slip. In addition usually adopts the ratchet pawl the mechanicalanti reverse device, can not be automatically releasedinversion energy, the need for manualoperation, there are serious security hidden danger; Polished rod is directly driven by themotor connection direct drive screw pump, improve transmission efficiency, but due to thelack of speed reducer, motor of the same powercannot meet the requirement of torque, andwhen the rod reversal also cannot decrease the reverse torque at the end of the motor.Although application of dynamic soft brake device can automatically release reversal, but thedevice is more electronic components, short service life and frequent replacement. So theresearch of new screw pump with high efficiency transmission mechanism, as well as antireverse device, is of great significance for the safe and efficient production of oil field.The new offset type screw pump drive system using high performance plane two stagereducer, this paper focuses on the model driven electromagnetic brake system on the basis ofthe. By using SolidWorks3D modeling software, after calculation, completed the design ofanti reverse device of the electromagnetic brake, and numerical simulation analysis. Thecalculation results show that the braking electromagnetic brake torque is designed in thispaper to218.2N·m, if in accordance with the gear reduction ratio10~15, the maximum torqueto the output shaft of the speed reducer is driven rod can reach2182~3273N·m, cancompletely meet the braking ordinary screw pump rod reversal need. Stress analysis resultsshow that the device can meet the strength requirements. The PLC design, completeelectromagnetic special intelligent brake control system, under the control of the system, theelectromagnetic brakedevice can effectively stop the sucker rod reversal, and canautomatically release the reverse torque, effectively reduce the reversal caused by pumpingrod breaking accident, also prolong the use period, improve safety performance.Analysis of the mechanism of screw pump well torque release, the two stage is discussedin detail in part two rod string reversal of the form, one is the rod itself stored elastic energyinversion stage, another is the oil pressure differential caused similar to the hydraulic motoreffectstage. This paper obtains the relationship equation between two stages of rod string unconstrained inversion process inangular velocity, angular acceleration and the reversal time.Theory has practical significance for the research of rod reversal, and brake electromagneticbraking device on the release time interval has a guiding significance.