The Configuration Design And Performance Analysis Of New Type Multi-Well Pumping Unit

In oilfield development, pumping unit is playing dominant role as mechanical equipment. Its excellent performance is the key for high efficient oil exploitation. In recent years, oil exploitation is coming into the mid, or even later stage. Oil storage capacity is declining; output and efficiency are also decreasing. Single-well pumping units cannot meet the principle of high efficiency and energy saving in oil exploitation. Thus, based on a research project cooperated with Shengli Oilfield Group, from the perspective of energy saving, this paper focuses on the research of new energy-saving multi-well pumping units, to solve the problems in oil exploitation field: low exploring efficiency, large energy consumption, and management inconvenience owing to separated work of single-well pumping units. The main research work and achievements are as follows:1. Configuration design of new energy-saving multi-well pumping unitsTo meet the tendency of energy saving and to adapt the process requirements of cluster wells, especially to save electrical energy, we decide to use one motor to implement the exploring of several wells (4-8 wells). Therefore, mechanical balancing and method of configuration of the so called cluster well pumping unit—one pumping unit for exploitation of several wells is studied. Several independent intellectual property machinery,for instance: disc pattern, coaxial pattern, and chain sprocket pattern and so on, are designed as new pumping unit configuration of driven reversing mechanism in jungle pattern. As a result, mechanical balancing and high efficiency are gained; in order to achieve the goal of energy saving, output increasing and economic benefit improving.2. Analysis and calculation of loadings on polished rodsThe loading property of polished rods and stress states of steel wires on polished rod are studied. According to different operating condition, rational and easy loading calculation equations are obtained. The inner relationship of loadings on polished rods and factors such as stroke, frequency of stroke, inclined angle of the well and viscosity of the oil are found out. In order to make the calculation of loadings on polished rods more convenient, the principle of parameter determination on operating conditions is concluded. In the cycle of operation, the changing rules of loading calculation on polished rods are discussed, in order to find out ways of decreasing the peak value of loadings on polished rods. This research will provide theoretical basis for balancing design of wells dynamically and kinetically.3. Design, calculation, and property study of a"new eight well non-beam pumping machine"This machine was detailed designed, and its performance was studied. The study for that machine included its kinematic and dynamic analyses, dimensional optimization, and determination of related parameters. Results from calculation of practical experiments show that this type of multi-well pumping unit can save energy by 25.8% compared with single-well pumping units. The influence of parameters such as stroke, frequency of stroke, inclined angle of the well and viscosity of the oil on performance of the pumping unit were investigated. Those research of this machine present a direct method to decline the peak value of motor power for the purpose of energy saving.4. Design analysis and property study of a"new four well beam pumping machine"This configuration is gladly accepted by the Shengli Oil Group. This new four well beam pumping machine was detailed designed, and its performance was studied. The study for that machine included its kinematic and dynamic analyses, determination of related parameters, and its energy saving effect data. Results from calculation of practical experiments show that this type of multi-well pumping unit can save energy by 30%. Moreover, the number of gearboxes was reduced which make the structure more convenient, and the configuration design technology is proficient as well. This solution is the best choice for Shengli Oilfield.5. Design analysis and property study of a"new four well chain pumping machine"A new four well chain pumping machine was detailed designed, and its performance was studied. Kinematics of the roundtrip shelf was detailed and precisely analyzed. Parameters were carefully chosen. This provides basis of calculation and design later. Calculation results show that chain pumping units work in uniform linear motion, so that its loadings are steady with low impulsive level. However, the torque curves add together rather than offset or balance. Thus, this type of pumping unit don't perform well in energy saving. Therefore, this type of pumping unit is excluded in energy saving of multi-well pumping unit.6. Analysis of malfunctions of multi-well pumping unit, and its solution discussPossible malfunctions of the multi-well pumping unit were discussed. According to the possible malfunctions of"one unit for 4 wells"pumping unit, two solving methods were given up: balance weight addition and phase angle adjustment. Those two methods have their own advantages and disadvantages. The selection should depend on particular operating conditions.