Electro-hydraulic high-pressure oilfield pumping system
AssigneeTwin Disc, Incorporated
InventorEdwin E. Wilson
Life of this patent
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Abstract
An electro-hydraulic high-pressure oilfield pumping system includes a fracturing (frac) pump and a primary electric motor as a prime mover that delivers power to the frac pump. The primary electric motor may be a constant speed AC (alternating current) motor. A hydraulic starting motor may rotate a shaft of the primary electric motor to achieve or approximate its fixed rated speed before the primary electric motor is energized. A slow frac hydraulic motor may rotate the shaft of the primary electric motor as a passive torque transmission device that delivers power in a downstream direction through a transmission and to the frac pump.
Claims18
An electro-hydraulic high-pressure oilfield pumping system for driving a fracturing (frac) pump configured to pressurize a frac fluid for delivery into a well that extends into a subterranean geological formation, comprising:
- a primary electric motor that has a motor shaft and defines a prime mover of the electro-hydraulic high-pressure oilfield pumping system;
- a transmission with multiple ranges that provide multiple drive ratios, the transmission arranged between and configured to deliver power from primary electric motor to the frac pump;
- a starting motor selectively delivering power through the transmission to rotate the motor shaft of the primary electric motor;
- and
- wherein the starting motor is a hydraulic motor that defines a hydraulic starting motor.
An electro-hydraulic high-pressure oilfield pumping system, comprising:
- a fracturing (frac) pump configured to pressurize a frac fluid for delivery into a well that extends into a subterranean geological formation;
- a primary electric motor that has a motor shaft and defines a prime mover of the electro-hydraulic high-pressure oilfield pumping system;
- a transmission with multiple ranges that provide multiple drive ratios, the transmission arranged between and configured to deliver power from primary electric motor to the frac pump;
- a hydraulic starting motor selectively delivering power through the transmission to rotate the motor shaft of the primary electric motor;
- a slow frac hydraulic motor selectively delivering power through the transmission to rotate the motor shaft of the primary electric motor;
- a hydraulic power pack configured to selectively permit or prevent flow of hydraulic fluid to each of the hydraulic starting motor and the slow frac hydraulic motor for activating or deactivating the hydraulic starting motor and the slow frac hydraulic motor.
A method of fracking a subterranean formation using a primary electric motor, the method including the steps of:
- driving the primary electric motor with a starting motor;
- driving a frac pump with an output of the primary electric motor to facilitate fracking the subterranean formation;
- selectively delivering power from the primary electric motor to the frac pump using a transmission;
- wherein the primary electric motor is a constant speed AC motor;
- and
- wherein the starting motor is a hydraulic starting motor and the method further comprises the step of, in a starting mode, driving the hydraulic starting motor with a second electric motor, and rotating a motor shaft of the primary electric motor with the hydraulic starting motor to a first speed that corresponds to a fixed rated speed of the primary electric motor.
Dependencies are inferred from the claim text.