Effect of back pressure increase on the pump efficiency of a pump

The influence of the increase of back pressure in energy environment on the pumping efficiency of the pump The simplified design of the Xu Weiqing No. 6 oil field of the No. 1 Oil Production Plant of Daqing Oilfield Co., Ltd. and the process flow of the ground pipeline (for ring and tree processes). The recovery oil pressure of the production well is rising due to the increase of the viscosity of the crude oil and the narrowing of the diameter of the pipe. Many of the average oil return pressures of the produced coal have risen from the original 0.3 MPa to UMpa-0.9 MPa. It was found that the return oil pressure has a great influence on the oil and the production volume of the liquid, and the single-well production fluid drops significantly after the back pressure rises, and the past pump efficiency theoretical calculation formula has never considered the back pressure factor. With the calculation of the return pressure and the recorded loss, we have obtained a theoretical calculation of the relationship between the high back pressure and the efficiency loss by analyzing various aspects of the pump efficiency loss.

Through the working principle of the pump, we know that the main pumping efficiency loss of the pump is due to the following three points: 1. Stroke loss 2. Loss loss 3. Filling coefficient The loss of the pump is mainly due to the gap between the active cold and the pump. With the loss of Versaille and the loss of the fixed part, Verr's loss t is mainly related to Versail's T. for state and crude oil properties, so the back pressure will not be taken into account for loss of t.

The formula for the calculation of the fuel pump clearance gap t: = (1) q - the leakage of the pump clearance M, cm3/s v - the kinematic viscosity of the object, cm3/sI - the length of the piston, m g - the acceleration of the steering, cm/s2e - diameter To clearance, cmVP-piston movement speed, cm/s is calculated in il, only parameter A// is related to back pressure, back pressure tip adds considerable d to increase the liquid pressure at piston h end, and the liquid density in the well is approximated as lxl ( Tkg/m3, for each increase in back pressure, the liquid column is 100m, that is, the parameter AH is increased by 100 meters, so the increase in the back pressure will increase the leakage of the pump's gap, ft, and kh is the back pressure, the MPa, and the gap loss. The variable relationship of t with back pressure can be expressed as: The increase in pressure, and the increase of the gap loss pump efficiency loss: Through this formula, you can quantitatively calculate the back pressure and pump N gap leakage relationship.

However, due to gap leakage 81 and active cold associated with the pumping gap, it will increase over time as the gap increases.

2. The allowable full-factor, the allowable full-size coefficient is mainly related to the liquid supply capacity at the bottom. The liquid supply capacity is not related to the back pressure, so the back pressure has no effect on the allowance factor.

3, the impact of back pressure on the stroke loss, stroke loss calculation formula is: - rush fi loss, m the calculation formula does not consider the impact of M pressure on the rod in the process of il calculation of the rod deformation, and in The pometro fruit machine actually performs the process. The back pressure has an effect on the rod load. The force acting on the piston on the up stroke: f = Kh (fp -, and this force will increase the elastic deformation of the rod , that is to increase the stroke loss.The force acting on the liquid during the down stroke does not affect the living cold and thus has no effect on the deformation of the sucker rod, so the back pressure increase H is to increase the elasticity of the sucker rod during the upstroke. Deformation: The elastic deformation of the tubing during the up and down stroke is mainly due to the gravitational loading of the liquid column, and thus has nothing to do with the back pressure, so the back pressure rises and the elastic deformation of the tubing: t Off, it can be concluded that the back stroke loss is affected by the back pressure U calculation formula should be due to the increase of N pressure, increase the stroke loss and then cause the pump efficiency loss is: As mentioned above, the back pressure increase mainly increases the stroke loss and clearance loss increase the pumping efficiency loss of pumping, back pressure caused The total pump efficiency loss t can be calculated by the following formula: