Point-By-Point Calculation of the Time Variation of the Polished Rod Load in Sucker Rod Pumped Oil Wells

Developed is an analytical analysis from which a synthesized dynamometer card can be calculated and plotted from generally known oil well parameters. The analysis preserves the time of displacement variable necessary for the calculation of instantaneous loads at any time or any position of the polished rod throughout the pumping cycle. The nonlinear boundary conditions introduced by the fluid pump are linearized and result In the applicability of superposition of loads in proper phase relationship. From the synthesized dynamometer cards various pumping conditions may be investigated; surface and subsurface equipment selected; and malfunction of system components determined.