Single-machine double-pump energy-saving hydraulic control system suitable for multiple machines and tools

Abstract

The invention provides a single-machine double-pump energy-saving hydraulic control system suitable for multiple machines and tools, which relates to the technical field of petroleum drilling and comprises a single-machine double-pump group, a parallel operation reversing valve group and a multi-path output valve group, the single-machine double-pump set comprises a main motor, a main pump and an auxiliary pump, and the main motor drives the main pump and the auxiliary pump to rotate; the input port of the parallel operation reversing valve group is connected with the output ports of the main pump and the slave pump, and is used for limiting the outlet pressure of the main pump and the slave pump and controlling the flow direction of hydraulic oil in the multi-path output valve group; and an input port of the multi-path output valve group is connected with an output port of the parallel operation reversing valve group and is used for controlling hydraulic oil to be output from different output ports. The double pumps in transmission connection with the main motor are adopted, the main pump and the auxiliary pump are coaxially connected in series, manual reversing control is carried out on output of the main pump and the auxiliary pump, meanwhile, energy-saving output of the main pump and the auxiliary pump is achieved through load feedback of the machine tool, and therefore the double-pump hydraulic machine tool is suitable for working requirements of various hydraulic machine tools, easy and convenient to operate and wide in applicability.

Description

Technical Field

[0001] This invention relates to the field of oil drilling technology, and more specifically, to an energy-saving hydraulic control system suitable for multi-tool single-machine dual-pump system. Background Technology

[0002] In oil drilling and workover operations, conventional hydraulic control systems are widely used. These systems are applicable to a limited range of hydraulic tools and lack load feedback output. Furthermore, during prolonged continuous operation, the working system can overheat, severely impacting the performance of hydraulic components. Summary of the Invention

[0003] The purpose of this invention is to provide an energy-saving hydraulic control system suitable for multi-machine single-machine dual-pump system, so as to solve one or more problems mentioned in the background art.

[0004] To achieve the above objectives, an energy-saving hydraulic control system suitable for multi-machine single-pump dual-operator systems is provided, comprising a single-pump dual-unit assembly, a parallel directional valve assembly, and a multi-output valve assembly. The single-pump dual-unit assembly includes a main motor and a main pump and a slave pump electrically connected to the main motor. The main motor drives the main pump and the slave pump to rotate. The main pump and the slave pump are used to draw hydraulic oil from the oil tank and deliver it to the parallel directional valve assembly. The input port of the parallel directional valve assembly is connected to the output ports of the main pump and the slave pump, used to limit the outlet pressure of the main pump and the slave pump, and to control the flow direction of hydraulic oil in the multi-output valve assembly. The input port of the multi-output valve group is connected to the output port of the parallel reversing valve group to regulate the output pressure of the machine, the feedback of the output load, and control the output of hydraulic oil from different output ports.

[0005] Preferably, the parallel reversing valve group includes a manual reversing valve, a first check valve 1 and a second check valve, and the multi-output valve group includes an output valve block and a first hydraulically controlled reversing valve and a second hydraulically controlled reversing valve disposed on the top surface of the output valve block. The hydraulic oil from the main pump is connected to the high-pressure input port of the first hydraulic directional valve via the first check valve, and the hydraulic oil from the secondary pump is connected to the high-pressure input port of the second hydraulic directional valve via the second check valve.

[0006] Preferably, both the first hydraulic directional valve and the second hydraulic directional valve include two control ports, and the manual directional valve includes two control ends, which are respectively connected to the two control ports of the first hydraulic directional valve and the second hydraulic directional valve. The hydraulic oil is output in separate circuits after being controlled by the manual directional valve.

[0007] Preferably, the parallel reversing valve assembly includes a first relief valve and a second relief valve. The first relief valve is a safety valve for the main pump, used to limit the maximum pressure of the main pump; the second relief valve is a safety valve for the slave pump, used to limit the maximum pressure of the slave pump.

[0008] Preferably, the multi-output valve group further includes a first pressure reducing valve, a second pressure reducing valve, and a throttle valve; the first pressure reducing valve is used to adjust the output pressure of the P3 output port, and the second pressure reducing valve is used to adjust the output pressure of the output port P2; the output ports of the first hydraulic directional valve and the second hydraulic directional valve are also load pressure ports. The hydraulic oil output port on the left side of the first hydraulic directional valve is connected to output port P3 through the first pressure reducing valve; one of the hydraulic oil output ports on the right side of the first hydraulic directional valve is connected to output port P2 through the second pressure reducing valve, and the other is connected to output port P1 through the throttle valve. The hydraulic oil output port on the left side of the second hydraulic directional valve is closed, and the pump is in a low-pressure standby state with no hydraulic oil output. The hydraulic oil on the right side of the second hydraulic directional valve is directly connected to the output port P2, and the hydraulic oil output port of the second hydraulic directional valve 2 is connected to the load feedback port of the pump.

[0009] Preferably, the multi-output valve group further includes a shuttle valve, the hydraulic oil output port on the left side of the first hydraulic directional valve is connected to the first input port of the shuttle valve, the hydraulic oil output port on the right side of the first hydraulic directional valve is connected to the second input port of the shuttle valve, and the output port of the shuttle valve is connected to the main pump load feedback port.

[0010] Preferably, the switching of the first hydraulic directional valve and the second hydraulic directional valve is controlled by a manual directional valve; when the manual directional valve is in the left position, the first hydraulic directional valve and the second hydraulic directional valve switch to the left position at the same time, and the hydraulic oil is output from P3 to achieve medium pressure and medium flow output. When the manual directional valve is in the right position, the first hydraulic directional valve and the second hydraulic directional valve simultaneously switch to the right position. The hydraulic oil of the first hydraulic directional valve is output from P1 and P2 respectively, achieving high pressure and low flow output. The hydraulic oil of the second hydraulic directional valve is directly output from the output port P2. At this time, the hydraulic oil output from the output port P2 is simultaneously output by the main pump and the slave pump, achieving medium pressure and high flow output.

[0011] Preferably, when the manual directional valve is in the neutral position, there is no control oil input to the first hydraulic directional valve and the second hydraulic directional valve. At this time, the first hydraulic directional valve and the second hydraulic directional valve are in the neutral position, and the main pump and the slave pump are in a low-pressure standby state with no hydraulic oil output.

[0012] Preferably, the hydraulic oil output from output ports P1, P2 and P3 is input to the corresponding external return ports after being used by hydraulic tools. The hydraulic oil from the external return ports is cooled by the air cooler and filtered by the return oil filter before returning to the oil tank.

[0013] Compared with the prior art, the beneficial effects of the present invention are: The energy-saving hydraulic control system provided by this invention adopts a dual pump connected to the main motor. The dual pumps are a main pump and a slave pump connected in series on the same axis. The output of the main pump and the slave pump is manually reversed. At the same time, the load feedback of the tool is used to realize the energy-saving output of the main pump and the slave pump. Therefore, it is suitable for the working needs of various hydraulic tools, and is easy to operate and has wide applicability. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of a hydraulic control system applicable to a multi-machine single-machine dual-pump energy-saving hydraulic control system according to the present invention; Figure 2 This is a schematic diagram of a hydraulic station applicable to a multi-machine single-machine dual-pump energy-saving hydraulic control system according to the present invention; Figure 3 This is a schematic diagram from another perspective of the hydraulic station used in the energy-saving hydraulic control system of a single machine with dual pumps for multiple machines according to the present invention; Figure 4 This is a schematic diagram of the main structure of a parallel reversing valve group in a multi-machine single-machine dual-pump energy-saving hydraulic control system according to the present invention; Figure 5 This is a side view of the parallel reversing valve group in an energy-saving hydraulic control system for multiple machines with a single machine and dual pumps, according to the present invention. Figure 6 This is a top view schematic diagram of a parallel reversing valve group in a multi-machine single-machine dual-pump energy-saving hydraulic control system of the present invention; Figure 7 This is a front view schematic diagram of a multi-output valve group applicable to a multi-machine single-machine dual-pump energy-saving hydraulic control system of the present invention; Figure 8 This is a side view of a multi-output valve group structure applicable to a multi-machine single-machine dual-pump energy-saving hydraulic control system of the present invention; Figure 9 This is a top view schematic diagram of a multi-output valve group in an energy-saving hydraulic control system for multiple machines and single-machine dual-pump systems according to the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] It should be noted that all uses of "first", "second", "third" and "fourth" in the embodiments of the present invention are for the purpose of distinguishing two entities with the same name but different names or different parameters. It is clear that "first", "second", "third" and "fourth" are only for the convenience of expression and should not be construed as limiting the embodiments of the present invention. Subsequent embodiments will not explain this in detail.

[0017] In the description of this invention, it should be understood that the terms "center," "lateral," "longitudinal," "front," "rear," "left," "right," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0018] This invention provides an energy-saving hydraulic control system suitable for multi-machine single-machine dual-pump systems, including a single-machine dual-pump group 3, a parallel reversing valve group 4, and a multi-output valve group 5. It should be noted that the high-pressure ports described in this embodiment correspond to the high-pressure input ports, i.e., input ports, of each control valve. The control valves include a first hydraulically controlled reversing valve, a second hydraulically controlled reversing valve, and a manual reversing valve, etc.

[0019] The single-unit dual-pump assembly 3 includes a main motor 3.1 and a main pump 3.2 and a slave pump 3.3 electrically connected to the main motor. The main motor 3.1 drives the main pump 3.2 and the slave pump 3.3 to rotate. The main pump 3.2 and the slave pump 3.3 are used to draw hydraulic oil from the oil tank 1 and deliver it to the parallel reversing valve assembly 4. The input port of the parallel reversing valve assembly 4 is connected to the output port of the main pump 3.2 and the slave pump 3.3 to limit the outlet pressure of the main pump 3.2 and the slave pump 3.3, and to control the flow direction of hydraulic oil in the multi-output valve assembly. The input port of the multi-output valve assembly 5 is connected to the output port of the parallel reversing valve assembly 4 to adjust the output pressure of the machine, the feedback of the output load, and to control the output of hydraulic oil from different output ports.

[0020] It should be noted that the control system of this application is applied to a hydraulic power unit, which includes an oil tank, a suction filter, a single-unit dual-pump assembly, a parallel directional valve assembly, a multi-way output valve assembly, an air cooler, a return filter, a pressure gauge assembly, and a frame. All components are installed inside the frame, resulting in a compact structure and ease of operation. The hydraulic oil from each of the above-mentioned lines, after passing through the hydraulic tool and being cooled by the air cooler, is filtered by the return filter before returning to the oil tank.

[0021] like Figure 1-3As shown, specifically, the parallel directional valve group 4 includes a manual directional valve 4.5, a first check valve 4.1, and a second check valve 4.2. The multi-output valve group includes an output valve block 123 and a first hydraulically controlled directional valve 5.1 and a second hydraulically controlled directional valve 5.2 disposed on the top surface of the output valve block. The manual directional valve 4.5 is an oil flow direction selection valve, which controls the flow direction of the oil in the first hydraulically controlled directional valve and the second hydraulically controlled directional valve. The first check valve and the second check valve are used to ensure that there is no reverse flow of hydraulic oil between the main pump and the slave pump.

[0022] The hydraulic oil from the main pump passes through the first check valve 4.1 to the high-pressure input port of the first hydraulic directional valve 5.1, while the hydraulic oil from the secondary pump passes through the second check valve 4.2 to the high-pressure input port of the second hydraulic directional valve 5.2.

[0023] like Figure 1-3 As shown, both the first hydraulic directional valve 5.1 and the second hydraulic directional valve 5.2 include two control ports, and the manual directional valve 4.5 includes two output terminals, which are respectively connected to the two control ports of the first hydraulic directional valve 5.1 and the second hydraulic directional valve 5.2. The hydraulic oil is output in separate paths after being controlled by the manual directional valve. It should be noted that the manual directional valve has three control ports, namely the first control port 108, the second control port 109, and the neutral return port 105. The first control port 108 and the second control port 109 are respectively connected to the first control port and the second control port of the multi-way output valve group, and the neutral return port 105 is connected to the oil tank; the parallel valve block return port 111 is connected to the first return port of the multi-way output valve group.

[0024] As shown in the figure, the parallel reversing valve assembly 4 also includes a first relief valve 4.4, a second relief valve 4.3, a first pressure gauge 9.2, and a second pressure gauge 9.1. The first relief valve 4.4 is the main pump safety valve. The first check valve 4.1 is connected to the oil return line of the oil tank through the first relief valve 4.4, and the second check valve 4.2 is connected to the oil return line of the oil tank through the second relief valve 4.3, used to limit the maximum pressure of the main pump. The second relief valve 4.3 is the slave pump safety valve, used to limit the maximum pressure of the slave pump. The output end of the first check valve 4.1 is connected to the first pressure gauge 9.2, and the output end of the second check valve 4.2 is connected to the second pressure gauge 9.1.

[0025] The parallel operation directional control valve assembly includes a first relief valve 4.4, a second relief valve 4.3, a first check valve 4.1, a second check valve 4.2, a manual directional control valve 4.5, a parallel operation valve block 112, and connecting screws 110. All the valve components are mounted on the parallel operation valve block 112, which is connected to the frame of the hydraulic control system via connecting screws 100. It should be noted that the parallel operation valve block has two high-pressure input ports and two high-pressure output ports, namely a first input port 101, a second input port 103, a first output port 106, and a second output port 107. The parallel operation valve block also has two pressure ports, namely a main pump pressure test port 102 and a slave pump pressure test port 104. The first input port 101 and the second input port 103 are connected to the output ports of the main pump and the slave pump, respectively. The first output port 106 and the second output port 107 are connected to the first and second input ports of the multi-way output valve assembly, respectively.

[0026] like Figure 1-3 As shown, the multi-output valve group 5 includes a first hydraulically controlled directional valve 5.1, a second hydraulically controlled directional valve 5.2, a first pressure-reducing valve 5.4, a second pressure-reducing valve 5.3, a throttle valve 5.5, an output valve block 123, and connecting screws 127, etc.; Figure 4-9 As shown, all the above-mentioned valve components are installed on the top surface of the output valve block, which is fixed to the frame by connecting screws 127. The output valve block has two high-pressure input ports and two control ports, including a first high-pressure input port 128, a second high-pressure input port 129, a first reversing control port 113, and a second reversing control port 114. Here, the first reversing control port 113 and the second reversing control port 114 correspond to the control ports of the first hydraulically controlled directional valve 5.1 and the second hydraulically controlled directional valve 5.2, respectively. In addition, there are three output high-pressure ports and three load feedback ports. The output high-pressure ports are the output ports P1, P2, and P3 of the hydraulic station. The load feedback ports are the first feedback port 124, the second feedback port 116, and the third feedback port 119. Pressure gauges are connected to the output pipelines of the three load feedback ports, forming three pressure measuring ports: the first pressure port 125 of the valve group, the second pressure port 126 of the valve group, and the third pressure port 118 of the valve group. The load feedback port provides feedback to the main pump and slave pump based on the actual needs of the machine, thereby enabling the main pump and slave pump to output on demand, greatly improving the economy and energy efficiency of the hydraulic system. The multi-output valve group has two internal return ports: a first return port 122 and a second return port 117. The first return port 122 is connected to the return port 111 of the parallel valve block, and the second return port 117 is connected to the inlet of the air cooler. Three external return ports are also provided: T1, T2, and T3.

[0027] Preferably, it also includes a return oil pipeline. The hydraulic oil output from the hydraulic station's output ports P1, P2, and P3 is input to the corresponding three external return oil ports after being used by the hydraulic tools. The external return oil ports are T1, T2, and T3. An air cooler and a return oil filter are installed on the return oil pipeline between the external return oil ports and the oil tank. The hydraulic oil from each external return oil port is cooled by the air cooler and filtered by the return oil filter before returning to the oil tank.

[0028] It should be noted that the hydraulic station has a compact structure, is easy to disassemble, and isolates heat energy. The frame includes two sides, one side with a two-sided structure for housing the parallel directional valve group and the multi-way output valve group, and the other side for housing the oil tank and motor, etc. The oil tank is a hydraulic oil storage container; the air cooler cools the hydraulic oil and improves the working environment of the hydraulic components; the parallel directional valve group and the multi-way output valve group are the control and output valve groups of the entire hydraulic system, and the two are arranged in an upper and lower structure on one side of the frame; the upper layer is the parallel directional valve group for easy switching operation, and the lower layer is the multi-way output valve group for easy pipeline installation and removal; the upper part of the parallel directional valve group is equipped with a pressure gauge assembly, which includes various pressure gauges corresponding to the main pump pressure, the slave pump pressure, the P1 port pressure, the P2 port pressure, and the P3 port pressure respectively; the explosion-proof power distribution cabinet is the control system of the electrical components of the entire hydraulic station, controlling the start and stop of the main motor and the air-cooled motor.

[0029] It should be noted that the first pressure reducing valve 5.4 is used to regulate the output pressure of port P3, and the second pressure reducing valve 5.3 is used to regulate the output pressure of port P2; the output ports of the first hydraulic directional valve 5.1 and the second hydraulic directional valve 5.2 are also load pressure ports. Figure 1 As shown, the hydraulic oil output port on the left side of each hydraulic control directional valve is output port A, and the hydraulic oil output port on the right side is output port B.

[0030] The left hydraulic oil output port of the first hydraulic directional valve 5.1 is connected to the first pressure reducing valve 5.4, and the other end of the first pressure reducing valve 5.4 is connected to the output port P3; one of the hydraulic oil output ports on the right side of the first hydraulic directional valve 5.1 is connected to the output port P2 through the second pressure reducing valve 5.3, and the other is connected to the output port P1 through the throttle valve 5.5. The hydraulic oil output port on the left side of the second hydraulic directional valve 5.2 is closed, and the pump is in a low-pressure standby state with no hydraulic oil output. The hydraulic oil on the right side of the second hydraulic directional valve 5.2 is directly connected to the output port P2, and the hydraulic oil output port of the second hydraulic directional valve 5.2 is connected to the load feedback port of the pump.

[0031] The multi-output valve group 5 also includes a shuttle valve 12. The hydraulic oil output port of the first hydraulic control directional valve 5.1 on the left is connected to the first input port of the shuttle valve 12, the hydraulic oil output port of the first hydraulic control directional valve on the right is connected to the second input port of the shuttle valve 12, and the output port of the shuttle valve 12 is connected to the main pump load feedback port.

[0032] The innovation of this invention lies in the use of a dual-pump system connected to the main motor. The main pump and the slave pump are coaxially connected in series. The outputs of the main and slave pumps are manually controlled for reversing. The outlets of the main and slave pumps are respectively connected to the first and second input ports of a parallel reversing valve group. The first and second control ports of the parallel reversing valve group are respectively connected to the first and second reversing control input ports of a multi-output valve group. Different output ports are achieved through manual reversing of the parallel reversing valve group, making it suitable for various hydraulic tools. When hydraulic oil is input to the first reversing control input port of the multi-output valve group, both the main pump and the slave pump output simultaneously, meeting the requirements of high-flow-rate tools. When hydraulic oil is input to the second reversing control input port of the multi-output valve group, the main pump outputs, while the slave pump remains in a low-pressure standby state, meeting the requirements of low-flow-rate tools.

[0033] Specifically, the hydraulic control process is described as follows: the switching of the first hydraulic control directional valve and the second hydraulic control directional valve is controlled by a manual directional valve. During control, the manual directional valve can perform three operations, including pushing forward, neutral position, and pulling back.

[0034] Forward push: When the manual directional valve handle is pushed forward, the first hydraulic directional valve and the second hydraulic directional valve simultaneously switch to the right position. At this time, hydraulic oil is input. The hydraulic oil of the main pump passes through port B of the first hydraulic directional valve. One path is reduced by the second pressure reducing valve and output to port P2. The other path passes through the throttle valve and output to port P1, achieving high pressure and low flow output. The hydraulic oil of the slave pump passes through port B of the second hydraulic directional valve and is directly output to port P2. P2 combines the output flow of the main pump and the slave pump, resulting in a large flow output.

[0035] Pull back: When the manual directional valve handle is pulled back, the first hydraulic directional valve and the second hydraulic directional valve switch to the left position simultaneously. At this time, hydraulic oil is input. The hydraulic oil of the main pump passes through port A of the first hydraulic directional valve, and after being depressurized by the first pressure reducing valve, it is output to the output port P3. The hydraulic oil of the slave pump passes through port A of the second hydraulic directional valve. Since the output port A is closed, the slave pump is in a low-pressure standby state at this time, and there is no pressure oil output.

[0036] Neutral Position: When the manual directional valve handle is in the neutral position, this is the system start position, and the main motor is started. There is no control oil input to the first and second hydraulic directional valves; the valve cores are in the neutral position under the action of the return spring. At this time, the first and second hydraulic directional valves are in the neutral position, and the main pump and slave pump are in a low-pressure standby state with no hydraulic oil output. When the external equipment is not in use, the handle should be placed in the neutral position. In the neutral position, the readings of all pressure gauges in the hydraulic control system are zero.

[0037] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. An energy-saving hydraulic control system suitable for single-machine dual-pump operation in multi-tool applications, characterized in that, Including a single-unit dual-pump group (3), a parallel reversing valve group (4), and a multi-output valve group (5); The single-unit dual-pump assembly (3) includes a main motor (3.1) and a main pump (3.2) and a slave pump (3.3) electrically connected to the main motor. The main motor (3.1) drives the main pump (3.2) and the slave pump (3.3) to rotate. The main pump (3.2) and the slave pump (3.3) are used to absorb hydraulic oil from the oil tank (1) and deliver it to the parallel reversing valve assembly (4). The input port of the parallel reversing valve group (4) is connected to the output ports of the main pump (3.2) and the slave pump (3.3) to limit the outlet pressure of the main pump (3.2) and the slave pump (3.3) and to control the flow direction of hydraulic oil in the multi-way output valve group; The input port of the multi-output valve group (5) is connected to the output port of the parallel reversing valve group (4) to control the output of hydraulic oil from different output ports.

2. The energy-saving hydraulic control system for multi-machine single-machine dual-pump as described in claim 1, characterized in that, The parallel reversing valve group (4) includes a manual reversing valve (4.5), a first check valve (4.1) and a second check valve (4.2), and the multi-output valve group includes a first hydraulically controlled reversing valve (5.1) and a second hydraulically controlled reversing valve (5.2). The hydraulic oil of the main pump is connected to the high-pressure input port of the first hydraulic directional valve (5.1) via the first check valve (4.1), and the hydraulic oil of the slave pump is connected to the high-pressure input port of the second hydraulic directional valve (5.2) via the second check valve (4.2).

3. The energy-saving hydraulic control system for single-machine dual-pump multi-tools according to claim 2, characterized in that, The first hydraulic directional valve (5.1) and the second hydraulic directional valve (5.2) each include two control ports. The manual directional valve (4.5) includes two control ends, which are respectively connected to the two control ports of the first hydraulic directional valve (5.1) and the second hydraulic directional valve (5.2). The hydraulic oil is output in separate circuits after being controlled by the manual directional valve.

4. The energy-saving hydraulic control system for multi-machine single-machine dual-pump as described in claim 3, characterized in that, The multi-output valve group (5) further includes a first pressure reducing valve (5.4), a second pressure reducing valve (5.3), and a throttle valve (5.5); the first pressure reducing valve (5.4) is used to adjust the output pressure of output port P3, and the second pressure reducing valve (5.3) is used to adjust the output pressure of output port P2; the output ports of the first hydraulic directional valve (5.1) and the second hydraulic directional valve (5.2) are also load pressure ports; The hydraulic oil output port on the left side of the first hydraulic directional valve (5.1) is connected to the output port P3 through the first pressure reducing valve (5.4); one of the hydraulic oil output ports on the right side of the first hydraulic directional valve (5.1) is connected to the output port P2 through the second pressure reducing valve (5.3), and the other is connected to the output port P1 through the throttle valve (5.5); The hydraulic oil output port on the left side of the second hydraulic directional valve (5.2) is a closed port. The slave pump is in a low-pressure standby state with no hydraulic oil output. The hydraulic oil on the right side of the second hydraulic directional valve (5.2) is directly connected to the output port P2. The hydraulic oil output port of the second hydraulic directional valve (5.2) is connected to the load feedback port of the slave pump.

5. The energy-saving hydraulic control system for single-machine dual-pump multi-tools according to claim 3, characterized in that, The multi-output valve group (5) also includes a shuttle valve (12). The hydraulic oil output port on the left side of the first hydraulic control directional valve (5.1) is connected to the first input port of the shuttle valve (12). The hydraulic oil output port on the right side of the first hydraulic control directional valve is connected to the second input port of the shuttle valve (12). The output port of the shuttle valve (12) is connected to the main pump load feedback port.

6. A multi-machine single-machine dual-pump energy-saving hydraulic control system according to claim 5, characterized in that, The switching of the first hydraulic control directional valve (5.1) and the second hydraulic control directional valve (5.2) is controlled by the manual directional valve (4.5); When the manual directional valve (4.5) is in the left position, the first hydraulic directional valve (5.1) and the second hydraulic directional valve (5.2) are simultaneously switched to the left position, and hydraulic oil is output from the output port P3 to achieve medium pressure and medium flow output; When the manual directional valve (4.5) is in the right position, the first hydraulic directional valve (5.1) and the second hydraulic directional valve (5.2) are simultaneously switched to the right position. The hydraulic oil of the first hydraulic directional valve is output from P1 and P2 respectively, realizing high pressure and low flow output. The hydraulic oil of the second hydraulic directional valve is directly output from the output port P2. At this time, the hydraulic oil output from the output port P2 is simultaneously output by the main pump and the slave pump, realizing medium pressure and high flow output.

7. A multi-machine single-machine dual-pump energy-saving hydraulic control system according to claim 6, characterized in that, When the manual directional valve (4.5) is in the neutral position, the first hydraulic directional valve (5.1) and the second hydraulic directional valve (5.2) have no control oil input. At this time, the first hydraulic directional valve (5.1) and the second hydraulic directional valve (5.2) are in the neutral position, and the main pump and the slave pump are in a low-pressure standby state with no hydraulic oil output.

8. The energy-saving hydraulic control system for single-machine dual-pump multi-tools according to claim 1, characterized in that, The hydraulic oil output from output ports P1, P2 and P3 is input to the corresponding external return ports after being used by hydraulic tools. The hydraulic oil from the external return ports is cooled by the air cooler (7) and filtered by the return oil filter (8) before returning to the oil tank (1).

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