Oil Field Indispensable Equipment, Sucker Rod

Characteristics of sucker rod

A sucker rod is a steel rod,typically between 25 and 30 feet (7 to 9 meters) in length,and threaded at each end.Sucker rod is an important component part of the pumping unit.Pumping power by the sucker rod string is passed to the deep well pump,made deep well pump piston reciprocating motion Sucker rods made of fiberglass in 37 1/2 foot lengths and diameters of 3/4,7/8,1,and 1 1/4 inch are also commonly available.

Main applications of sucker rod

Sucker rod is mainly used in the equipment of oil exploitation.There are three main devices applied in the oil exploitation,which is high pour point,high viscosity and high wax content.

• Hollow sucker rod electric heating device

  The hollow sucker rod electric heating device is one of the most important applications of hollow sucker rod. Put the heating cable into the hollow sucker rod, when the power is connected, it will generate inner skin effect, the electric energy will be transformed to the thermal energy to heat the crude oil. This device can reduce the viscosity and wax content of the crude oil and guarantee the normal production.
  There is a special device of the electric heating device. It adopts the drive rod for screw pump to instead of the common hollow sucker rod. The drive rod for screw pump has higher tensile strength and fracture resistance than the common hollow sucker rod. So, the screw pump electric heating device is ideal for the extremely strict environments of high efficiency exploitation.

• The hollow sucker rod hot carrier heating device

  The hollow sucker rod electric heating device is one of the most important applications of hollow sucker rod. Put the heating cable into the hollow sucker rod, when the power is connected, it will generate inner skin effect, the electric energy will be transformed to the thermal energy to heat the crude oil. This device can reduce the viscosity and wax content of the crude oil and guarantee the normal production.
  There is a special device of the electric heating device. It adopts the drive rod for screw pump to instead of the common hollow sucker rod. The drive rod for screw pump has higher tensile strength and fracture resistance than the common hollow sucker rod. So, the screw pump electric heating device is ideal for the extremely strict environments of high efficiency exploitation. Hollow sucker rod hot carrier heating is mainly used for heating the crude oil which is high viscosity, high pour point and high wax content. Inject the hot carrier into the hollow sucker rod to heat the crude oil. The hot carrier will not enter the oil pipe, so it will not pollute the oil and reduce pollution.

• Circular heating device

  Circular heating device is the most important application of the double hollow sucker rod. It using the associated biofuels, solar energy and other heat sources to heat the circular media to enter the inner channel of the double hollow sucker rod, the circular media will flow into the outer channel of the double hollow sucker rod driven by the high pressure. Pass through the four-way hanging connector and return the ground return pipe to form a closed circular system. The circular media will not contact with the crude oil and has no loss of it. Additional, the associated biofuels and solar energy are all the clean energy, so the device is clean, green and high efficiency device to exploit the high pour point, high viscosity and high wax content crude oil.

Advantages for sucker rod

In general, the advantages of continuous sucker rod are as follows：

• Because there is no coupling, it can effectively reduce the wear between the pump rod and tubing wall.
• Common sucker rod connecting part is easiest to failure fracture, however, the design of the continuous sucker rod is cancelled fitting, which can greatly reduce the failure frequency of sucker rod.
• Reduce the load of pumping unit：Because there is no collar, when sucker rod move in the oil, the friction is on the decrease so that the total energy consumption is greatly reduced, and Continuous sucker rod under the same circumstances, the well depth is deeper.
• Sucker rod can undertake continuous operation, which greatly simplifies the operation process. Due to the failure frequency of decrease at the same time, reduce work times and corresponding operation cost greatly reduced.

Two kinds of sucker rod

At present, the domestic production and application of continuous sucker rod is mainly steel continuous sucker rod andcarbon fiber continuous sucker rod (Flexible continuous sucker rod).

Steel continuous sucker rod refers to the metal continuous sucker rod, Its cross section is approximately oval, which can be used in the conventional pumping unit and the oil pump. Compared with the flexible continuous rod, the operating equipment of steel continuous sucker rod is more complex, and the transportation is inconvenient, and the corrosion resistance is poor. But because of its high reliability, the operation speed is faster, and the fatigue strength is higher, it currently used more widely.

The flexibility of carbon fiber rod is good. With a small winding drum, it's easy for transportation but can only sustain tension. The most important is that the operating temperature is limited. And the price is not so reasonable.

Conclusion

With the continuous development of manufacturing process and material properties, the development and application of continuous sucker rod is becoming more and more extensive, and its performance advantages will be more and more outstanding. But we should realize that there are still many problems in the practical application of the continuous sucker rod, Timely summary and actively seek resolution strategy, in order to make the technology more able to adapt to oilfield development