Ultra long stroke flexible rod pumping unit is a new type of mechatronics tower pumping unit developed by Sanjack. The whole system is mainly composed of eight parts: motor, drum, frequency conversion control cabinet, frame, movable block, counterweight, brake and loss of load protection device, flexible rod and foundation. It is a new type of intelligent long stroke pumping unit in petroleum industry.

The frame is taken as the carrier and the switched reluctance motor as the power source, and drives the drum to rotate through the tooth belt, and the drum is equipped with a decelerating device. The inverter controls the forward and backward rotation and speed regulation of the motor. The distribution box is pulled with movable pulley and polymer rope, and the lifting point load is pulled with flexible optical rod. By winding and releasing the flexible rod on the drum, the reciprocating movement of the rod is realized. Through disc electromagnetic brake device, the motor can be stopped in time to ensure safety.
The counterweight end of the ultra-long stroke flexible rod pumping unit is wrapped around a set of moving pulleys to lengthen the stroke of the pumping unit. It has the following advantages: simple structure, small footprint, long stroke, low stroke frequency, easy maintenance, etc.
The forward and reverse operation of the motor is effectively controlled by the frequency conversion control program and the auxiliary stroke switch device, so as to realize the stepless adjustment of the motor speed. Compared with the traditional beam pumping unit, its parameter adjustment is more convenient. The ELECTRICAL control program has the functions of overload protection, phase loss protection, motor overheating protection, short circuit shutdown and power failure protection, which makes the equipment more intelligent and safe. When the pumping unit loses load, the braking and load loss protection device can maximize the safety of personnel and equipment.

Working principle

The motor drives the drum (the shell is the drum, and the motor has built-in reducer) to rotate through the belt.
The flexible polished rod is wound in the middle of the drum, and the rod is connected to the wellhead load through the guide wheel at the front end.
Both ends of the drum are wound with wire rope with a heavy box, and the positive and negative rotation of the drum is driven by the positive and negative rotation of the motor to realize the swabbing operation. The pumping unit can achieve the stepless adjustment of stroke and stroke frequency in particular range.