Fluid loss reduction between a cylinder and plunger during operation is the most important requirement to the design of a bottom-hole sucker-rod pump. Fluid loss reduction in the clearance between a cylinder and plunger increases the pump efficiency. Current methods for leakage control do not provide the intended effect. As the pump runs, the gap between the cylinder and plunger increases due to wear, resulting in fluid leakage increase. An attempt to use a hydraulic seal does not provide the intended effect as well. Over time, the seal is washed out and loses its functionality. Therefore, there is a need to develop more reliable, simple and effective control methods against this harmful phenomenon.
This paper proposes using the hydrostatic head pressure (which leads to fluid leakage) to reduce leakage. This is achieved by opening the side angle holes in the plunger. Mathematical model is developed and fluid leakage at the clearance between cylinder and piston of the pump with presence of holes on the lateral surface is determined. Numerical calculation is performed and threshold values of lateral holes’ coordinates are determined, excess of which makes them inoperative. Level of leakage reduction is determined depending on parameters of the lateral holes.
References
1. Mirzadzhanzade A.Kh., Gurbanov R.S. et al., Teoriya i praktika primeneniya glubinnykh nasosov s gidravlicheskim zatvorom (Theory and practice of the use of submersible pumps with a hydraulic gate), Moscow: Nedra Publ., 1986, 210 p.
2. Dragotesku N.D., Glubinno-nasosnaya dobycha nefti (Artificial oil lift), Moscow: Nedra Publ., 1996, 418 p.
3. Pisarik M.N., Calculation of leaks through the gap of a well pump rod when pumping out of watered oil (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1982, no. 7, pp. 49-50.
4. Gurbanov R.S, Mamedova M.A, Gurbanova T.G., Development of the sealing method of the pump clearance by well production (In Russ.), Vostochno-evropeyskiy zhurnal peredovykh tekhnologiy = Eastern-European Journal of Enterprise Technologies, 2015, no. 5/1 (77), pp. 59-62.
5. Patent no. 2350784 RF, Rod sub-surface pump with side aperture in cylinder plugged with hydraulic overflow valve, Inventors: N Ibragimov N.G., Taziev M.Z., Zakirov A.F., Latfullin R.R., Zubarev S.M.
6. Patent no. 2140571 RF, Sucker rod pump, Inventors: Shurinov V.A., Pykhov S.I., Kozlovskiy A.M., Bezzubov A.V.
7. Patent no. 2309295 RF, Borehole pump plunger, Inventor: Lepekhin Yu.N.
8. Bakhtizin R.N., Urazakov K.R., Latypov B.M., Ishmukhametov B.Kh., Fluid leakage in a sucker-rod pump with regular micro-relief at surface of the plunger (In Russ.), Neftegazovoe delo, 2016, no. 4, рр. 33–39.
9. Wiggins M.L., Chapter 1. Inflow and outflow performance, In: Petroleum Engineering Handbook, SPE, 2007, 900 p.
10. Shi G.B., Neftyanye emul'sii i metody bor'by s nimi (Oil emulsions and methods of their control), Moscow – Leningrad: Gostoptekhizdat Publ., 1964, 144 p.
11. Levchenko D.N. et al., Emul'sii nefti s vodoy i metody ikh razrusheniya (Emulsions of oil with water and methods for their destruction), Moscow: Khimiya Publ., 1967, 29 p.
