The Characteristic Research And Energy Efficiency Evaluation Of Pumping Units, Rods And Pumps

For reducing energy consumption and adapting the complicated conditions in oil well,many types of energy-efficient pumping units, rods, pumps are applied. But the study ofmotion characteristics of different types of pumping units, rods, pumps and Energy-savingeffect comparison is lacking. The choice of pumping units is difficult. So basing on themotion characteristics of pumping units(conventional beam-pumping unit, different phasefloat frame pumping unit, deformed pumping unit, adjustable diameter torque pumping unitand belt type pumping unit), we had built the ground efficiency calculation model. On thebasis of the motion characteristics of pumping units,rods (steel rod, fiberglass rod, continuousrod and so on)and pumps(the conventional subsurface pump, the dynamic cylinder sandcontrol pump, the immersion pumping viscous pump, the hydraulic feedback type pumpingviscous pump, the load shedding deep suction pump),using the wave equation (or calledGibbs Equation), the law of suspension center motion and the operation of bottom holepump, the calculation model of lifting efficiency and system efficiency had been set up. Andwe also had analyzed the movement and stress of the rod string by the finite elementsoftware-Algor. The result are as follows, under the condition of a given production,theTorque of all the modified pumping units dropped, all of the modified pumping units canimprove system efficiency and power-saving rate when compared with the conventionalbean-pumping unit.Compared with the steel sucker rod string, the polished rod load of fiberglassrod string is reduced, If the percentage of length of the fiberglass rod is right,the rod sting willhave super stroke phenomenon.The polished rod load of the rod string can be reduced if therod is wire rope sucker rod, but it does not have super stroke phenomenon. The polished rodload of the rod string can be reduced if the rod is the steel continuous sucker rod. Its plunger strokeand system efficiency is higher than the steel sucker rod string’ when the unit has long stroke and highimpact time.Compared with the conventional pump, the changes of the plunger load and systemefficiency of the travelling barrel sand control pump are small. Because of the specialstructures of the immersion pumping viscous pump and the Hydraulic feedback type pumpingviscous pump, there is a downward hydraulic feedback force at down stroke, which ensure their good adaptability for heavy oil well, compared with the conventional pump, lever underthe column load-stroke difference between the system efficiency decreases.The load sheddingdeep suction pump has two plungers which diameters are different, when at up stroke, as theupper piston diameter is smaller, the plunger is smaller, when at down stroke, the action ofsubmergence pressure is helpful for the downward of rod column and the load difference isreduced. Compared with the other four pumps, the load shedding deep suction pump’s loaddifference is smallest, and the system efficiency is biggest.The result of the movement andstress of the rod string by the finite element software-Algor shows that the software has goodmechanical simulation effect, the relative error of system parameter is0.36%-8.54%.Theresult shows that simulating the movement and stress of the rod by using the Algor isfeasible，meanwhile, the Algor can predict the behavior accurately, so we can select the rodreasonable. TheAlgor has important guiding significance to improve the system efficiency.