External Rotor Electric Motor Pumping Unit
External Rotor Electric Motor Pumping Unit is a new type of pumping unit in petroleum industry. Compared with the traditional walking beam pumping unit, it saves the gear reducer and crank, pitman mechanism, and improves the transmission efficiency. The unit frame works as the carrier of all the structure, the AC external rotor permanent magnet synchronous motor is the power source of the pumping unit.
External rotor electric motor pumping unit is a electromechanical integrated tower pumping unit newly developed by our company. The whole system is composed of eight parts: external rotor motor, variable frequency control panel, unit frame, movable pulley group, counterweight, brake and load-loss protection device, wire line, base and so on. It is a new type of pumping unit in petroleum industry. Compared with the traditional walking beam pumping unit, it saves the gear reducer and crank, pitman mechanism, and improves the transmission efficiency. The unit frame works as the carrier of all the structure, the AC external rotor permanent magnet synchronous motor is the power source of the pumping unit. The variable frequency control technology is used to control the motor positive and negative rotation and its speed. The external rotor, movable pulley, wire line and counter weight constitute the traction system. The sucker rod moves up and down through the flexible wire line. The brake device installed outside of the external rotor can brake the unit in time when the motor stops to ensure safety. As the gear reducer is saved, there is no high speed rotation part in the unit and the mechanical design is reasonable. In order to reduce the load of the power source and increase the driving force, a set of movable pulleys are equipped at the sucker rod end and the counterweight end respectively to make the equipment more energy-saving and efficient. The whole unit has the characteristics of simple structure, small volume, long stroke, low frequency and convenient maintenance.
Variable frequency control program and auxiliary stroke switching device can effectivelycontrol the motor reversing movement and realize stepless adjustable speed of the motor. Compared with the traditional beam pumping unit, it has the advantages of convenient adjustment of parameters. The electrical control program has the functions of overload protection, phase-missing protection, motor overheat protection; short-circuit power-off protection, so that the equipment is more intelligent and safe. Brake and loss of load protection device can play the greatest role in protecting the safety of personnel and equipment when the loss of load occurs.
In a word, external rotor electric motor pumping unit is a new type of electromechanical integration pumping unit with the characteristics of energy saving, emission reduction, safety and intelligence.
It makes a good sale in ShengLi oilfield, ZhongYuan oilfield, LiaoHe oilfield, DaGang oilfield and Huabei oilfield, etc.
- Power saving: Compared with conventional beam pumping units, the average power saving rate is up to 30%.
- Efficiency improvement: Compared with conventional beam pumping units, the production efficiency can be increased by 30% on average.
- Noise reduction: Since there is no intermediate deceleration mechanism, the noise is low. The measured noise is below 40dB.
- Deep well production: especially suitable for operations requiring long stroke, low stroke and deep pumping with small pump.
- Space saving: especially suitable for high density of small space.
- Easy to operate: 0-3 times stepless adjustment can be achieved in the adjustment of stroke, and 0-12 meters can be customized according to user requirements.
- Simple and convenient maintenance: The conventional beam pumping unit has as many as 35 fault points, and the machine has only 6 maintenance points.
When the sucker rod is going up, the counterweight is less than the sucker rod load, and the motor rotates counterclockwise to output torque to help the counterweight lift the sucker rod;When the sucker rod descends, the sucker rod load is less than the counterweight, and the motor rotates clockwise to output torque to help the sucker rod lift the counterweight. The reciprocating movement of the sucker rod is realized by the periodic forward and reverse of the motor.
Since the counterweight is the average value of the maximum load and the minimum load, the positive and negative rotation work of the motor is basically equal.
The core components
Permanent magnet motor with constant torque
- Conventional oil
- Deep wells
- Thermal wells
- Light, medium, and some of heave crude
- Vertical, slant , deviated, and some of horizontal well application
- Dewatering natural gas and coalbed methane
- Operations requiring energy savings
- Operations requiring lower noise (only 48 decibels,
ultra low-noise design is suitable for quiet environment.)
- Wells that experience frequent downhole equipment failures because of friction.
External rotor electric motor pumping unit from Sanjack Petro, Dongying City, Shandong Province, China.
|Polished rod load (kN)||120||140|
|Classification condition||Long stroke ow SPM|