In recent years, Screw pump In terms of lifting supporting technology, the screw pump oil production technology research was carried out to reduce the cost of mechanical oil production. The field application experiment proves that the screw pump has outstanding economy. Compared with the pumping units with the same lifting ability, the one-time input and power consumption of the screw pump are greatly reduced. Moreover, the service life of screw pumps in China's oil fields has exceeded 1600 days, and the maintenance free period of some wells has exceeded 1000 days. In the process of tackling the key problems of screw pump matching technology, in view of the problem of the rod string that restricts the development of large and medium displacement screw pump, a key experiment was carried out on the screw pump sucker rod, which is mainly composed of the plug-in anti stripping rod and the drill pipe taper thread anti torsion rod. Compared with the conventional sucker rod, it decreased 9.98 percentage points; In addition, the wellhead sealing method, motor foundation and motor base were improved, the wellhead sealing effect was improved, and the operation stability of ground equipment was improved. The large displacement screw pump used in Daqing Oilfield has been operating for 645 days.

    ALLWEILER Three screw pump It is a positive displacement rotor pump, which absorbs and discharges liquid by the displacement of several sealing cavities formed by the screw tooth shape in the pump and the pump sleeve. The three screw pump with no theoretical leakage channel between two adjacent sealing cavities in the three screw pump is called a severely sealed three screw pump, and vice versa.

Three screw pump is widely used. It is characterized by stable flow, small pressure fluctuation, self-priming ability, low noise, high efficiency, long life, small size and reliable operation. The outstanding advantage is that no eddy current is formed when transporting media, and various media with wide viscosity can be transported. It can not only transport lubricating or corrosive media with various viscosities, but also transport non-newtonian liquids with various viscosities, as well as gas-liquid mixed transportation and solid-liquid mixed transportation. It is widely used in marine channel engineering, petrochemical industry, shipping, electric power, mechanical hydraulic system, food, paper making, sugar making, military industry, sewage treatment and other industrial sectors.

Operation process of screw pump:

1. The construction process, characteristics and equations of various cycloids are introduced. This paper introduces the design method of screw pump linetype - the design process of inverse solution. This paper introduces the specific design method and process of the rotor and stator linetype of screw pump, and derives the equation of the profile, thereby deducing the equation of the profile.

2. The linear composition principle and process of the rotor and stator of the 3G screw pump are messy, involving many parameters. Through analysis, the basic parameters required to form the linear structure of the screw pump are determined.

3. The meshing process and rules of the rotor and stator in the operation process of the single screw pump are analyzed, and the rotor tooth convex contact point and the rotor tooth concave contact point are derived from the fixed contact point and flow contact point between the rotor and the stator bone line.

4. The composition principle of the rotor and stator linetype of the thermal insulation screw pump is the external rolling method. In the process of composition, it is equivalent to that the rotor does not move and the stator moves in a planetary manner. When the screw pump is operating in practice, the stator does not move and the rotor moves in planetary motion. In order to conform to the practical motion mode of the screw pump, the mathematical expression of sliding speed is derived in three ways. Therefore, the relationship between the parameters of the two motion modes is analyzed and deduced.

5. The relative sliding speed formula of the convex tooth contact point and concave tooth contact point of the stainless steel screw pump rotor relative to the stator is analyzed and deduced respectively. Through the analysis of the specific model, it is shown that the sliding speed of the convex tooth contact point is small at the concave stator and large at the middle point of the convex stator; The sliding speed of the tooth concave contact point is higher at the moment of breaking away from the inner concave of the stator, and is lower at the middle point of the inner convex of the stator; The large value of the sliding speed of the concave contact point is the small value of the sliding speed of the convex contact point.

6. The method of analyzing the sliding speed of the general internal swing type three screw pump is applied to the single head ordinary internal swing type high viscosity screw pump widely used in oil fields, which greatly simplifies the analysis process. After that, the size and distribution rules of the relative sliding speed between the rotor and stator of GLB800 screw pump commonly used in the oil field are analyzed concretely and concretely.

III. Precautions before starting the screw pump are as follows:

one 、 The inlet of the three screw pump shall be equipped with a filter. Generally, the large particles passing through the filter shall not be greater than 0. Imm.

two 、 Check whether the three screw pump unit and the connecting part are firmly fixed; Check whether the connection between the suction pipe section and the external joint is sealed.

3、 Check whether there is clearance between the three screw pump couplings and strictly control the alignment of the two shafts. The runout of the outer circle of the coupling shall not exceed 0.05mm, and the end face runout of the coupling shall not exceed 0. Imme

4、 Before starting, the three screw pump shall be filled with operating medium.

5、 Check whether the suction valve on the inlet pipeline of the three screw pump and the discharge valve on the discharge pipeline are turned over.

6、 Roll the coupling of the three screw pump by hand. The screw rolling should be uniform and light, and there should be no rolling strain or jamming.