Hydraulic drive of drilling rig with pressure regulator

Abstract

FIELD: drilling machines.SUBSTANCE: invention relates to the field of drilling machines with volumetric hydraulic drive of working elements and is intended for automatic regulation of drilling parameters. The drilling rig's hydraulic drive comprises a pump station, containing an adjustable pump with a drive motor, safety valves, a filter and a tank, two electro-hydraulic distributors, a reversible hydraulic motor for driving the drill rotation, and a hydraulic cylinder for feeding the drilling tool. The electro-hydraulic distributors are designed as multi-position units. The hydraulic drive contains a hydromechanical pressure regulator connected to the cavities of the hydraulic motor of the drill rotation drive and the hydraulic cylinder of the drill feed by means of valves and including a multi-position hydraulic distributor with two hydraulic cylinders for regulating the working volume of the pump.EFFECT: increase in the stability of the operation of the drilling rig hydraulic drive in transient modes under the action of random loads and reduction in the power consumption when operating in low modes.1 cl, 1 dwg

Description

[0001] The invention relates to the field of drilling machines with a volumetric hydraulic drive of working bodies and is intended for automatic regulation of drilling parameters.

[0002] In conventional hydraulic drilling rigs, the rotation and feed of the working tools are independent, and the drilling speed is controlled by a throttle. However, in most cases, the soil being drilled is heterogeneous, and frictional resistance between the soil and the auger increases with increasing drilling depth. This leads to random external influences on the working tools and their hydraulic motors. The effect of variable loads results in underutilization of the drilling rig's drive motor, reducing efficiency. Automatic optimization of the drilling process is often not provided, and the operator manually selects the drilling mode based on their personal experience.

[0003] A drilling rig hydraulic drive is known, comprising a pumping station with a fixed pump, a reversible drilling hydraulic motor kinematically connected to the rig's actuator by a gearbox, and a drilling tool feed hydraulic cylinder connected in series with it. The hydraulic motors are activated and their movement is reversed by a three-position, four-way electro-hydraulic distributor. The speed of the hydraulic motors is varied by a throttle mechanism using a flow regulator installed parallel to the hydraulic motors and diverting a portion of the working fluid into a tank. Parallel connection of hydraulic motors improves the reliability of the hydraulic machine by synchronizing the feed force and torque on the hydraulic motor (USSR Author's Certificate No. 1518508, IPC E21 C 5 / 08, published 10 / 30 / 1989).

[0004] The disadvantage of this analogue is the reduction in the efficiency of the hydraulic drive due to the use of a throttle control method.

[0005] A drilling rig hydraulic drive is known, comprising a pumping station with an adjustable pump, a reversible drilling hydraulic motor connected to the rig's actuator via a gearbox, and an additional feed pump kinematically connected to it, which supplies power to the drilling tool feed hydraulic cylinder during the working stroke. The speed of the hydraulic motors can be varied by adjusting the characteristic working volume of the main pump. Increased machine productivity and reduced energy consumption are achieved by using special hydraulic distributors (USSR Author's Certificate No. 543733, IPC E21 B 5 / 00, published July 25, 1977).

[0006] The disadvantage of this analogue is the power take-off of the drilling rotation drive hydraulic motor to ensure the operation of the auxiliary pump and the back pressure in the rod cavity during the working stroke of the drilling tool feed hydraulic cylinder, which generally reduces the efficiency of the hydraulic drive.

[0007] The closest in technical essence and achieved result to the proposed hydraulic drive of the drilling rig is a hydraulic drive comprising a pumping station with an adjustable pump, a hydraulic cylinder for feeding the drilling tool and a reversible hydraulic drilling motor connected to the actuator of the rig by a gearbox. The speed of the hydraulic motors can be changed by adjusting the characteristic working volume of the pump. The activation of the hydraulic motors into operation and the reversal of movement is carried out by a three-position four-way electro-hydraulic valve. Partial automation of the drilling mode regulation in order to maximize the engine load of the base machine is achieved by the additional use of two reversible dividers of the working fluid flow and two hydraulic locks (patent for utility model No. RU 45443 U1, IPC E21 B 19 / 08, published 10.05.2005).

[0008] The disadvantages of the closest analogue include unstable operation under random and parallel loads, and significant static error of flow dividers using a throttle control method. Furthermore, significant power consumption is possible when operating at low speeds, as well as static error caused by the mutual influence of the rotation and feed circuits of the drilling tool under varying loads on the actuator hydraulic motors.

[0009] The objective of the invention is to expand the functional capabilities of the hydraulic drive of a drilling rig and ensure insensitivity to loads on the rotation and feed hydraulic motors.

[0010] The technical result of the claimed invention is to ensure stable operation in transient modes under the action of random loads, a reduction in power consumption during operation in low modes, and a static error under different loads on the executive hydraulic motors for rotation and feed of the working parts of the drilling machine, caused by the mutual influence of the circuits on each other.

[0011] The stated problem is solved, and the technical result is achieved by the fact that in the hydraulic drive of the drilling machine, containing a pump station, including an adjustable pump with a drive motor, safety valves, a filter and a tank, two electro-hydraulic distributors, a reversible hydraulic motor for the drill rotation drive and a hydraulic cylinder for feeding the drilling tool, unlike the prototype, the electro-hydraulic distributors are made multi-position, while it contains a hydromechanical pressure regulator connected to the cavities of the hydraulic motor for the drill rotation drive and the hydraulic cylinder for feeding the drill by means of valves and including a multi-position hydraulic distributor with two hydraulic cylinders for regulating the working volume of the pump.

[0012] The technical result is achieved by maintaining a constant hydraulic pressure in heterogeneous soil mining modes and under random loads, while in standby mode, power consumption is minimized by regulating the pump. When the drill drive hydraulic motor and the drill feed hydraulic cylinder are activated, the change in system pressure caused by a planned or random load change is transmitted to the hydraulic cylinders of the hydromechanical pressure regulator, which adjust the pump's characteristic working volume to the situation and maintain a constant system pressure.

[0013] The essence of the invention is explained by a drawing, which depicts a basic hydraulic diagram of a drilling rig hydraulic drive.

[0014] The drilling rig hydraulic drive comprises a pump station with an adjustable pump 1, a drive motor 2, a drill rotation drive hydraulic motor 3 and a drill feed hydraulic cylinder 4. The pump station also includes: safety valves 5, a tank 6 and a filter 7. Pump 1 is connected via pressure hydraulic lines to the circuits of the drill rotation drive hydraulic motor 3 and the drill feed hydraulic cylinder 4, which contain multi-position electro-hydraulic distributors 8. The cavities of the hydraulic motor 3 and the hydraulic cylinder 4 are connected via “or” valves 9 to a pressure regulator containing a multi-position hydraulic distributor 10 and two hydraulic cylinders 11 and 12 for controlling the characteristic working volume of pump 1.

[0015] The drilling rig hydraulic drive operates as follows. The working fluid from tank line 6 is supplied by pump 1 to drill rotation drive hydraulic motor 3 and drill feed hydraulic cylinder 4. When the corresponding electronic control signal is supplied to multi-position electro-hydraulic distributors 8, hydraulic motor 3 and hydraulic cylinder 4 are connected to the pump 1 discharge line and the operating mode is determined. The hydraulic motors operate at a speed determined by the control signals to multi-position electro-hydraulic distributors 8. When electro-hydraulic distributors 8 are reversed, the hydraulic motors (hydraulic motor and hydraulic cylinder) of the drilling rig are reversed. Safety valves 5 prevent hydraulic drive failure due to overload or filter clogging. By sucking fluid from tank 6, pump 1 also compensates for volumetric leaks in the hydraulic motors.

[0016] The pressure regulator in the drilling rig's hydraulic drive operates as follows. In the absence of control signals to the electro-hydraulic distributors 8, pump 1 reaches minimum output, controlling the minimum characteristic working volume of the pump using hydraulic cylinder 11. The piston of cylinder 12 is then displaced to the extreme left position. The pressure in the system is maintained constant at the nominal pump flow rate. When control signals are applied to electro-hydraulic distributors 8, the shaft of hydraulic motor 3 begins to rotate through the drilling rig's gearbox. Hydraulic cylinder 4 feeds the drilling tool. The consumption of working fluid from the pump increases. To compensate for the pressure drop, the pressure regulator is activated. The spring of multi-position hydraulic distributor 10 shifts the spool valve by an amount proportional to the pressure drop.At the same time, pressure is supplied to the piston chamber of hydraulic cylinder 12 via multi-position hydraulic distributor 10, changing the characteristic working volume of pump 1, increasing its flow rate and compensating for the pressure drop, bringing the value to the nominal pressure. The regulator sets the supply pressure sufficient to overcome the external load on the drill rotation hydraulic motor and the drill feed hydraulic cylinder, ensuring the best energy and dynamic characteristics. If the load on the drill (on the drill drive hydraulic motor or the drill feed hydraulic cylinder) is exceeded, for example due to increasing soil hardness, the pressure in the system increases. The pressure regulator receives information about the pressure increase via the "or" valves and reduces the pump's working volume, reducing the flow rate but maintaining a constant pressure in the system. This maintains a constant drill rotation torque, but at a lower speed.The drill's feed hydraulic cylinder also reduces the drill's travel speed. When the drill's load decreases, the pressure regulator increases the flow rate of pump 1 and correspondingly increases the speed of the drill's rotation and feed hydraulic motors. The pressure regulator automatically adjusts the drill's drive to account for soil inhomogeneity and drilling depth.

[0017] Thus, the claimed invention makes it possible to improve the stability of the drilling process and the energy efficiency of the drilling rig by maintaining a constant pressure in the multi-motor hydraulic drive, eliminating unstable operation in transient modes, minimal power consumption when operating in low modes, and a static error caused by the mutual influence of the circuits on each other under different loads on the actuator hydraulic motors.

Claims

A hydraulic drive for a drilling rig, comprising a pump station including an adjustable pump with a drive motor, safety valves, a filter and a tank, two electro-hydraulic distributors, a reversible hydraulic motor for driving the drill rotation, and a hydraulic cylinder for feeding the drilling tool, characterized in that the electro-hydraulic distributors are made multi-position, and also comprises a hydromechanical pressure regulator connected to the cavities of the hydraulic motor for driving the drill rotation and the hydraulic cylinder for feeding the drill by means of valves and including a multi-position hydraulic distributor with two hydraulic cylinders for regulating the working volume of the pump.

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