Fig 1.
Dynamic analysis model of hydraulically driven beam-pumping unit.
In Fig 1, where: A—the fore-arm length, mm; P—the link length, mm; Wt—the balance weight, kN; CF—the guide rail contact force kN; PF—the link force kN; C—the rear-arm length, C = C1 + C2, C1 is the length of the line GH and C2 is the length of the line EG, mm; Lp—the length of the line EF, mm; θ1~θ5—the auxiliary angles for analyzing its balance characteristic, rad; θ6—the constant angle of beam to horizontal line on the down die point, rad; θ7—the sliding guide tilt constant angle, rad.
Fig 2.
3D Model of conventional pumping unit.
Fig 3.
3D hydraulic drive pumping unit.
Fig 4.
1-Oil sump; 2-Electric plunger pump; 3-Pressure gauge; 4-Relief valve; 5-Differential pressure signal; 6-High pressure filter; 7-heat sink; 8-two-position four-way solenoid valve; 9-Control valve; 10-Hydraulic cylinder.
Table 1.
Structure size and operating parameters of pumping unit.
Table 2.
Well condition parameters.
Fig 5.
A flow chart for calculation procedures of the solution method.
Fig 6.
Suspension velocity versus time curve of hydraulically pumping unit.
Fig 7.
Movement curve on suspension of hydraulic pumping unit.
Fig 8.
Motion curve of suspension of conventional pumping unit.
Fig 9.
Simulation indicator diagram of conventional and hydraulically driven pumping units.
Fig 10.
Balance torque curve of conventional pumping unit.
Fig 11.
Torque curve of center shaft of hydraulically driven pumping unit.
Fig 12.
Virtual shaft torque curve of hydraulically driven pumping unit.
Fig 13.
Hydraulic drive pumping unit.
Table 3.
Oil well condition parameters.
Table 4.
Test comparison results.