Control method for different load emergency tests of crane

Abstract

According to the control method for the different load emergency tests of the crane, the winch is subjected to the no-load test, whether the debugging oil way is normal or not can be judged by observing whether rotation of the winch is normal or not, and meanwhile when an emergency situation occurs in the no-load state test process, the debugging oil way can be manually operated to be in an emergency state. The winch rotates again to continuously realize no-load test, so that the reliability of the manual emergency oil way for controlling the winch can be verified; when a load test is carried out, the flow of the hydraulic oil flowing from the oil pump unit to the multi-way valve is changed through the valve element stroke screw, so that the load test can be carried out under different hydraulic oil flows, whether the flow control of the oil way meets the actual operation requirement or not is judged through the test, and meanwhile, when an emergency situation occurs in the load state test process, the load test can be carried out. The winch in an emergency can be rapidly controlled to lower a loaded heavy object through the electric emergency oil way, and potential safety hazards caused by accidental touch operation to on-site operators are avoided.

Description

Technical Field

[0001] This invention relates to the field of crane technology, and more specifically to a control method for emergency testing of cranes under different loads. Background Technology

[0002] During the lifting test of a crane, it is often necessary to conduct different load tests and further verify the effectiveness of the emergency operating system during the different load tests. This ensures that the safety performance of the crane under different load conditions meets the operational requirements. At the same time, the test can also help to identify potential faults in a timely manner and optimize safety measures.

[0003] For example, Chinese patent document No. 202421509367.1, published on July 8, 2025, discloses a control system for rapid emergency response of a hydraulic crane, including a manual pump, a cylinder, a hoisting motor, and a hydraulic rotary motor; the hoisting motor is connected to the main valve via a winch control valve group; the winch control valve group includes a first shuttle valve, a balance valve, a second hydraulic directional valve, a one-way pressure reducing valve, a third hydraulic directional valve, a second speed regulating valve, a second hydraulically controlled one-way valve, a second replenishing valve, and a second shuttle valve; wherein port A is connected to port A1 via the second hydraulic directional valve, port B is connected to port B1 via the balance valve, and the first shuttle valve is connected in parallel between the A-A1 oil circuit and the B-B1 oil circuit; the middle position of the first shuttle valve is sequentially connected to the second shuttle valve, the second hydraulic directional valve, and the one-way pressure reducing valve; port FL is sequentially connected to the second replenishing valve, the second speed regulating valve, and the third hydraulic directional valve.

[0004] The aforementioned literature uses a combination of hydraulic directional valves and speed control valves to control the rapid emergency lowering and rotation of hydraulic cranes, thus solving the problem of slow emergency release speed; however, it does not conduct emergency adjustments for the crane under both no-load and loaded test conditions to ensure the safety of the crane when testing different loads. Summary of the Invention

[0005] The purpose of this invention is to provide a control method for emergency testing of cranes under different loads, which enables manual and electric emergency adjustments during no-load or load testing of the crane to ensure the safety of the testing process.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a control method for emergency testing of cranes under different loads, implemented through a hydraulic control system. The hydraulic control system includes an oil pump unit, a winch hydraulic system, a throttling oil circuit, a brake oil circuit, an electric emergency oil circuit, and a manual emergency oil circuit, comprising the following steps: S1 performs manual emergency testing of the winch under no-load conditions, including steps S1.1 to S1.2; S1.1 Adjust the pressure of the brake oil circuit to be equal to the pressure at the winch valve, start the oil pump unit, and let the hydraulic oil flow through the oil pump unit to the second multi-way valve and enter the hydraulic system of the winch. Then open the brake oil circuit in the oil storage state to release the winch brake and observe whether the winch rotates normally. S1.2 When the oil pump unit stops working during the winch's no-load state, open the manual pump in the manual emergency oil circuit. The oil in the tank enters the winch's hydraulic system through the manual emergency oil circuit and the throttling oil circuit. Adjust the throttling valve knob of the throttling oil circuit to gradually slow down the winch's rotation speed until the winch stops rotating. S2 performs an electric emergency test on the winch during the load test, including steps S2.1 to S2.2; S2.1 Hang a load on the wire rope of the winch, start the oil pump unit, and open the winch brake after the hydraulic oil of the oil pump unit is reversed through the second multi-way valve. Perform different weight load tests by adjusting the hydraulic oil pressure at the inlet and outlet of the second multi-way valve. Then, change the hydraulic oil flow of the second multi-way valve to drive different speeds to achieve load testing while keeping the oil pressure constant. S2.2 During the process of the winch being under load, the emergency solenoid valve in the electric emergency oil circuit is energized, and then the knob of the throttle valve is adjusted to control the descent speed of the load on the winch.

[0007] The above method first involves conducting an unloaded test on the winch using a manual emergency hydraulic circuit. Observing the winch's rotation allows for assessment of the hydraulic circuit's functionality, ensuring the winch's operating condition is normal and preventing errors during subsequent load tests. During this process, the manual pump can be manually activated, connecting the hydraulic oil tank to the winch and releasing the winch's brakes to restart the unloaded test. This verifies the reliability of the manual emergency hydraulic circuit in controlling the winch, improving safety. In the load test, the hydraulic oil pressure at the outlet and inlet of the second multi-way valve is adjusted to achieve different load weights, ensuring the hydraulic circuit is functioning correctly. Whether the circuit can adapt to lifting loads of different weights can be determined by adjusting the hydraulic oil flow rate at the outlet of the second multi-way valve by adjusting the valve core stroke screw. This allows the winch to be driven at different speeds under different hydraulic oil flow rates for load testing. The test determines whether the flow control of the oil circuit meets the actual operation requirements. At the same time, through the cooperation of the electric emergency oil circuit and the throttling oil circuit, the winch can be restarted to lower the load if it suddenly stops. The descent speed can be controlled by the throttling oil circuit, which can quickly control the lowering of the load in case of emergencies. This avoids accidental operation that may cause safety hazards to the on-site personnel and ensures that the operation process is not affected by operational errors.

[0008] Furthermore, the oil pump unit is provided in two parts, and step S1.1 also includes: The brake oil circuit forms a branch circuit from the oil inlet port D5 of the second multi-way valve and connects to the MEP interface of the winch's hydraulic system, thereby opening the winch brake.

[0009] The above settings allow the winch brake to be released before conducting a no-load test, so that the winch can rotate.

[0010] Furthermore, step S1.1 also includes: The control handle drives the hydraulic circuit of the cab to connect with ports a1 and b1 of the second multi-way valve, pushing the valve core of the second multi-way valve to switch directions. After switching, the second relief valve and the third relief valve are adjusted to a preset fixed value. Then, the valve core stroke screw in the second multi-way valve is adjusted to a preset stroke distance so that the hydraulic oil at the oil outlet port D19 and the oil inlet port D20 of the second multi-way valve is fixed at the pressure and flow rate to the hydraulic system of the winch, thereby driving the winch to rotate at a constant speed. It is also convenient to change the pressure value of the second relief valve and the third relief valve and the stroke distance of the valve core stroke screw, thereby driving the winch to rotate at different speeds.

[0011] The above settings allow for a no-load test of the winch before the load test. By observing whether the winch rotates normally, it is possible to determine whether the hydraulic circuit is functioning correctly. At the same time, it ensures that the winch is operating normally, thus avoiding test errors during the subsequent load test.

[0012] Furthermore, the oil pump unit includes two hydraulic pumps. The output end formed by the connection of the two hydraulic pumps is connected to the oil inlet interface D5 of the second multi-way valve. One end of the brake oil circuit is connected to the oil inlet interface D5 of the second multi-way valve, and the other end of the brake oil circuit is connected to the A20 interface. The A20 interface is connected to the MEP interface of the hydraulic system. The oil outlet of the second multi-way valve is provided with two interfaces, D18 and D19. The D18 interface is connected to the oil tank. The oil outlet interface D19 and the oil inlet interface D20 of the second multi-way valve are respectively connected to the MWA interface and the MWB interface of the hydraulic system.

[0013] With the above settings, when the pressure output of the oil pump unit meets the load lifting requirements, the flow rate of the hydraulic oil flowing from the oil pump unit to the second multi-way valve can be controlled, so that the flow rate of the hydraulic oil flowing through the second multi-way valve is different. This allows for load tests to be conducted under different hydraulic oil flow rates, thereby determining whether the flow control of the oil circuit meets the actual operation requirements.

[0014] Furthermore, the oil inlet port D5 of the second multi-way valve is connected to one end of the first relief valve, and the other end of the first relief valve is connected to the oil tank; the oil outlet port D19 of the second multi-way valve is connected to one end of the second relief valve, and the other end of the second relief valve is connected to the oil tank; the oil inlet port D20 of the second multi-way valve is connected to one end of the third relief valve, and the other end of the third relief valve is connected to the end of the second relief valve connected to the oil tank.

[0015] The above settings, through the function of the first relief valve, can control the hydraulic oil pressure entering the second multi-way valve, thereby protecting the entire second multi-way valve and acting as a main safety valve. The second relief valve protects the winch during the ascent process, preventing overload of the ascent oil circuit pressure. The third relief valve protects the winch during the descent process, preventing overload of the descent oil circuit pressure.

[0016] Furthermore, the brake fluid circuit includes a first shuttle valve, a second shuttle valve, and a pressure reducing valve T12. One end of the first shuttle valve is connected to the oil inlet interface D5 of the second multi-way valve, the other end of the first shuttle valve is connected to one end of the second shuttle valve, the other end of the second shuttle valve is connected to one end of the pressure reducing valve T12, and the other end of the pressure reducing valve T12 is connected to the A20 interface.

[0017] The above settings allow for the diversion of oil from the oil circuit entering the second multi-way valve to form a brake oil circuit, which directly acts on the brakes of the hydraulic system.

[0018] Furthermore, the electric emergency hydraulic circuit includes an electric emergency release pump and an emergency solenoid valve, and the manual emergency hydraulic circuit includes a three-way ball valve and a manual pump. One end of the ball valve is connected to the hydraulic oil tank, and the other end of the ball valve is connected to the electric emergency release pump and the manual pump respectively.

[0019] With the above settings, after opening ball valve one, the hydraulic oil in the hydraulic oil tank can enter the electric emergency release pump unit and the manual pump through ball valve one.

[0020] Furthermore, the P port of the emergency solenoid valve is connected to the electric emergency release pump, the A and C ports of the emergency solenoid valve are both connected to the T port of the first multi-way valve, the B port of the emergency solenoid valve is connected to one end of the three-way ball valve; the manual pump is connected to the other end of the three-way ball valve, the third end of the three-way ball valve is connected to one end of the ball valve, and the other end of the ball valve is connected to the hydraulic system of the winch.

[0021] With the above settings, hydraulic oil can flow into the first multi-way valve through the emergency solenoid valve, and then the second brake can be released by controlling the ball valve three to release the brake on the winch.

[0022] Furthermore, one end of the ball valve four is connected to one end of the directional control valve, and the other end of the ball valve four is connected to one end of the throttling oil circuit and the motor E port connected to the winch. The other end of the throttling oil circuit is connected to one end of the four-way interface, and the other end of the four-way interface is connected to the motor F port. The third end of the four-way interface is connected to one end of the shuttle valve, and the other end of the shuttle valve is connected to one end of the directional control valve. The other end of the directional control valve is connected to the first brake, and the fourth end of the four-way interface is connected to the MWA interface in the hydraulic system of the winch.

[0023] With the above setup, when the hydraulic oil drives the motor to rotate, the hydraulic oil flowing through the three-way interface simultaneously pushes the shuttle valve, which in turn connects with the reversing valve, causing the reversing valve to switch directions. This causes the first brake to release the winch brake, thereby enabling the winch to rotate and lower the load.

[0024] Furthermore, the throttling oil circuit includes a throttling valve, a non-adjustable flow valve, and a ball valve five. The throttling valve, the non-adjustable flow valve, and the ball valve five are connected in series. The non-adjustable flow valve is connected to one end of the three-way interface, and the ball valve five is connected to the motor E port and the other end of the ball valve four, respectively.

[0025] The above settings allow for adjustment of the amount of hydraulic oil passing through the throttling circuit via a throttle valve, thereby controlling the descent speed of the load. Attached Figure Description

[0026] Figure 1 This is a hydraulic diagram of the oil pump unit of the present invention.

[0027] Figure 2 This is a hydraulic diagram of the second multi-way valve of the present invention.

[0028] Figure 3 This is a hydraulic diagram showing the connection between the electric emergency oil circuit and the manual emergency oil circuit in this invention.

[0029] Figure 4 This is a hydraulic diagram of the winch hydraulic system of the present invention.

[0030] Figure 5 This is a hydraulic diagram of the second multi-way valve after it reverses. Detailed Implementation

[0031] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0032] like Figure 1-5As shown, a control method for emergency testing of cranes under different loads is described. A winch is installed on the crane. An oil pump unit is connected to an oil tank 80. The oil pump unit is connected to the winch's hydraulic system 3 via a second multi-way valve 22. The oil pump unit includes two hydraulic pumps 1. In this embodiment, the hydraulic pump model is A11VO260DRS, and the second multi-way valve 22 is a multi-way valve M7, which is existing technology and will not be described further. The output end formed by the connection of the two hydraulic pumps 1 is connected to the oil inlet interface D5 of the second multi-way valve 22. One end of the brake oil circuit is connected to the oil inlet interface D5 of the second multi-way valve 22, and the other end of the brake oil circuit is connected to the A20 interface. The A20 interface is connected to the hydraulic... The hydraulic system 3 is connected to the MEP interface. The oil outlet of the second multi-way valve 22 is provided with two interfaces, D18 and D19. The D18 interface is connected to the oil tank 80. The oil outlet interface D19 and the oil inlet interface D20 of the second multi-way valve 22 are connected to the MWA interface and MWB interface of the hydraulic system 3, respectively. In this way, when the pressure output of the oil pump unit meets the load lifting condition, the flow rate of the hydraulic oil flowing from the oil pump unit to the second multi-way valve 22 can be controlled, so that the flow rate of the hydraulic oil flowing through the second multi-way valve 22 is different. Thus, load tests can be carried out under different hydraulic oil flow rates, so as to determine whether the flow control of the oil circuit meets the actual operation requirements through the test.

[0033] The inlet port D5 of the second multi-way valve 22 is connected to one end of the first relief valve 51, and the other end of the first relief valve 51 is connected to the oil tank. The outlet port D19 of the second multi-way valve 22 is connected to one end of the second relief valve 6, and the other end of the second relief valve 6 is connected to the oil tank. One end of the third relief valve 71 is connected to the D20 port, and the other end of the third relief valve 71 is connected to the end of the second relief valve 6 connected to the oil tank and connected to the D18 port. Thus, during the winch's ascent under load, hydraulic oil flows from the D5 port into the second multi-way valve 22 and, through the action of the first relief valve 51, prevents excessive pressure of the hydraulic oil entering the second multi-way valve 22, acting as a main safety valve for the entire oil circuit. By turning the valve core stroke screw, the flow rate of hydraulic oil flowing through the second multi-way valve 22 can be controlled, resulting in different flow rates of hydraulic oil flowing through the second multi-way valve 22. After controlling the flow rate, the hydraulic oil flows out from the outlet port D19 of the second multi-way valve. The second relief valve 6 protects the hydraulic oil entering the winch hydraulic system 3, preventing overload of the hydraulic oil pressure entering the winch hydraulic system 3. Finally, the hydraulic oil in the winch hydraulic system 3 flows back to the second multi-way valve 22 through the D20 port. At the same time, the third relief valve 71 can relieve the pressure of the hydraulic oil flowing back to the second multi-way valve 22 to prevent excessive pressure, and the hydraulic oil flows back to the oil tank 80 through the D18 port of the second multi-way valve 22.

[0034] In this embodiment, the second multi-way valve 22 includes a first directional valve 221 and a second directional valve 222. The first port of the first directional valve 221 is connected to the fifth port, and the fifth port of the first directional valve 221 is connected to the D20 interface. The first port of the first directional valve 221 is connected to the D18 interface. The second port of the first directional valve 221 is connected to the first check valve 2210. The third port of the first directional valve 221 is connected to the second check valve 2211 and then to the other end of the first check valve 2210. The other end of 2211 is connected to the first end of the second directional valve. The second end of the second directional valve is not connected. The third end of the second directional valve is connected to the fourth port of the first directional valve 221 and then to the fifth and sixth ports of the first directional valve 221. The sixth port of the first directional valve 221 is connected to one end of the second relief valve 6. The seventh port of the first directional valve 221 is not connected and is connected to the D5 interface. In this embodiment, the first directional valve 221 is a 3-position 7-way directional valve and the second directional valve 222 is a 3-position 3-way directional valve.

[0035] like Figure 2 and Figure 5 As shown, after the first reversing valve 221 and the second reversing valve 222 switch, as follows: Figure 5 As shown, hydraulic oil from the oil pump unit is input through interface D5 to the first directional valve 221 after reversing and flows into the second directional valve 222. Then it is input to the first check valve 2211, and output to the second relief valve 6 through the connection of the third and sixth ports of the first directional valve 221. From the second relief valve 6, it is output to the third relief valve 71 and the D19 interface. The third relief valve 71 outputs to the D20 interface, and then through the first directional valve 221, it is output to the oil tank 80 through the D18 interface. This enables the hydraulic oil from the oil pump unit to be output from interface D19 after passing through the first directional valve 221 and the second directional valve 222, and then through the D20 interface to the D18 interface to be output to the oil tank after passing through the two relief valves.

[0036] The brake oil circuit includes a first shuttle valve T03 / 3, a second shuttle valve T03 / 1, and a pressure reducing valve T12. One end of the first shuttle valve T03 / 3 is connected to the oil inlet interface D5 of the second multi-way valve 22, and the other end of the first shuttle valve T03 / 3 is connected to one end of the second shuttle valve T03 / 1. The other end of the second shuttle valve T03 / 1 is connected to one end of the pressure reducing valve T12, and the other end of the pressure reducing valve T12 is connected to the A20 interface. It can divert the oil entering the second multi-way valve 22 to form a brake oil circuit. In this way, after the hydraulic oil in the second multi-way valve 22 flows to the hydraulic system 3 of the winch, the brake oil circuit directly acts on the brake of the hydraulic system 3 to open the winch brake.

[0037] The winch hydraulic system includes a first brake 2, a second brake 33, a throttling oil circuit 4, a reversing valve 5, and a winch 61. The electric emergency oil circuit includes an electric emergency release pump H22 and an emergency solenoid valve T17. The manual emergency oil circuit includes a three-way ball valve T15 and a manual pump H18. One end of ball valve H17 is connected to the hydraulic oil tank 80, and the other end of ball valve H17 is connected to one end of the electric emergency release pump H22 and one end of the manual pump H18. Thus, when ball valve H17 is opened, the hydraulic oil in the hydraulic oil tank 80 can enter the electric emergency release pump H22 and the manual pump H18 through ball valve H17.

[0038] The P port of the emergency solenoid valve T17 is connected to the other end of the electric emergency release pump H22. The A and C ports of the emergency solenoid valve T17 are both connected to the T port of the first multi-way valve H19. The B port of the emergency solenoid valve T17 is connected to the first end of the three-way ball valve T15. In this way, after the hydraulic oil in the hydraulic oil tank 80 flows into the three-way ball valve T16, the flow rate of the hydraulic oil flowing through the three-way ball valve T16 can be controlled to reach the first brake 2, thereby controlling the hydraulic oil pressure reaching the first brake 2, so that the first brake 2 releases the brake on the winch 61.

[0039] The other end of the manual pump H18 is connected to the second end of the three-way ball valve T15. One end of ball valve BV2 / 1 is connected to one end of the directional valve 5. The other end of ball valve BV2 / 1 is connected to one end of the throttling oil circuit 4 and the motor 7E port connected to the winch 61. The other end of the throttling oil circuit 4 is connected to one end of the four-way interface A02. The other end of the four-way interface A02 is connected to the motor 7F port. The third end of the four-way interface A02 is connected to one end of the shuttle valve 8. The other end of the shuttle valve 8 is connected to one end of the directional valve 5. The fourth end of the four-way interface A02 is connected to the MWA interface, and the other end of the reversing valve 5 is connected to the first brake 2. In this way, when the hydraulic oil drives the motor 7 to rotate, the hydraulic oil flowing through the four-way interface A02 pushes the shuttle valve 8, which in turn connects with the reversing valve 5, causing the reversing valve 5 to switch. This allows one of the reversing valves 5 to conduct oil input from the MEP port to the upper end of the first brake 2, causing the first brake 2 to release the winch 61 brake, thereby realizing the rotation of the winch 61 and driving the load to be lowered. In this embodiment, there are two reversing valves 5.

[0040] The throttling oil circuit 4 includes a throttling valve NQ1, a non-adjustable flow valve BR1, and a ball valve BV2 / 2. The throttling valve NQ1, the non-adjustable flow valve BR1, and the ball valve BV2 / 2 are connected in series. The non-adjustable flow valve BR1 is connected to one end of the four-way port A02, and the ball valve BV2 / 2 is connected to the other end of the motor 7E port and the ball valve BV2 / 1, respectively. Thus, the amount of hydraulic oil passing through the throttling oil circuit 4 can be adjusted by the throttling valve NQ1, thereby controlling the descent speed of the load.

[0041] In this embodiment, the first multi-way valve H19 includes an overflow valve H191 and a ball valve NV2. One end of the overflow valve H191 is connected to the C port of the solenoid emergency valve T17, and the other end of the overflow valve H191 is connected to one end of the ball valve NV2. The other end of the ball valve NV2 is connected to the D8 interface, which is also connected to one end of the ball valve BV2 / 4. The other end of the ball valve BV2 / 4 is connected to the control terminal of the second brake 33. The emergency solenoid valve T17 includes a solenoid directional valve YV60 and an overflow valve T171. The first port of the solenoid directional valve YV60 is connected to the output terminal of the solenoid valve T171. The second port of the electromagnetic directional valve YV60 is connected to the other end of the relief valve T171 and the C port; the first port of the electromagnetic directional valve YV60 is connected to the third port and the third port is connected to the T port of the first multi-way valve H19; the second port of the electromagnetic directional valve YV60 is connected to the fourth port and the fourth port is connected to the B port. When the emergency solenoid valve T17 is energized and does not switch directions after entering the electric emergency state, the hydraulic oil flowing out through the emergency electric pump flows into the first multi-way valve H19 through the P port and then flows into the second brake 33 to release the second brake 33.

[0042] The control method includes the following specific steps: S0 opens the butterfly valve 80 in the oil tank, filling the pipeline of the hydraulic system 3 with hydraulic oil, and checks the pipeline for leaks to prevent hydraulic oil leakage during the test.

[0043] S1 performs manual emergency testing of the winch under no-load conditions, including steps S1.1 to S1.4; S1.1 Detect the pressure at the winch valve MES, adjust the pressure of the pressure reducing valve T12 in the brake oil circuit to make the pressure of the pressure reducing valve T12 equal to the pressure at the winch valve MES. In this embodiment, the pressure of the pressure reducing valve T12 in the brake oil circuit is adjusted to 5MPa. Start the oil pump unit so that the hydraulic oil in the oil tank flows through the oil pump unit to the oil inlet port D5 of the second multi-way valve 22. The hydraulic oil at the oil inlet port D5 of the second multi-way valve 22 is diverted to form a brake oil circuit. In this way, the brake oil circuit is connected to the MEP interface of the hydraulic system of the winch after the diverted oil circuit is formed from the oil inlet port D5 of the second multi-way valve 22, so that the brake oil circuit is filled with hydraulic oil. S1.2 By controlling the handle, the hydraulic circuit in the cab is driven to allow oil to enter through ports a1 and b1 of the second multi-way valve 22, causing the second multi-way valve 22 to switch directions. After the switch, hydraulic oil flows from the outlet port D19 of the second multi-way valve 22 to the MWA port of the winch's hydraulic system. At this time, the directional valve 5 of the hydraulic system is opened (see...). Figure 4This causes the brake circuit to open the winch brake. The hydraulic oil then flows through the winch's hydraulic system, returning via the MWB interface to the inlet port D20 of the second multi-way valve 22, and then back to the oil tank 80 via port D18, forming a complete oil circuit. This drives the winch to operate unloaded for a period of time. During this process, the valve core of the second multi-way valve 22 is reversed, and the second and third relief valves are adjusted to preset fixed values. The valve core stroke screw in the second multi-way valve 22 is then adjusted to a preset stroke distance, ensuring that the hydraulic oil at both the outlet port D19 and the inlet port D20 of the second multi-way valve 22 flows to the winch's hydraulic system at a fixed pressure and flow rate, thus driving the winch to rotate at a constant speed. The pressure values ​​of the second and third relief valves and the stroke distance of the valve core stroke screw of the second multi-way valve 22 are then changed to drive the winch to rotate at different speeds, and the normal rotation of the winch is observed. S1.3 During the winch's no-load operation, when the oil pump unit 1 stops working, open ball valve H17 connected to the hydraulic oil tank 80, ball valve T16 connected to the second brake, ball valve BV2 / 1 connected to the throttling oil circuit 4, and ball valve BV2 / 2 in the throttling oil circuit, while simultaneously closing ball valve AV1 connected to the winch; then open the throttling valve NQ1 in the throttling oil circuit 4 and rotate the knob of the throttling valve NQ1 to the minimum value; S1.4 Switch the three-way ball valve T15 to manual emergency mode and manually open the manual pump H18. Hydraulic oil flows through the manual pump H18, through the three-way ball valve T15, into the ball valve T16, and then into the throttle oil circuit 4 and the motor E port. Then, adjust the knob of the throttle valve NQ1 to control the flow rate of hydraulic oil through the throttle oil circuit 4. The hydraulic oil flowing out of the motor F port merges with the hydraulic oil flowing through the throttle oil circuit 4 and flows into the four-way interface A02, and then into the shuttle valve 8. Pushing the shuttle valve 8, it flows into the reversing valve 5 to reverse the direction, allowing hydraulic oil to enter the control end of the first brake 2, causing the first brake 2 to release, thereby causing the winch to rotate and drive the load to descend. Upon reaching the ground, adjust the knob of the throttle valve NQ1 to control the flow rate of hydraulic oil through the throttle oil circuit 4, reducing the flow rate of hydraulic oil in the throttle oil circuit 4. This causes the oil pressure in another oil circuit 9 connected to the throttle oil circuit 4 to be greater than the oil pressure of the hydraulic oil at the output end of the throttle oil circuit 4, thereby pushing the shuttle valve 8 to move and block the hydraulic oil flowing out of the four-way interface A02. The control end of the second brake 2 will not supply oil. At this time, the brake pads of the first brake 2, under the action of the spring, squeeze out the hydraulic oil in the first brake 2, and through the reversing valve 5, switch to the right cavity and flow back to the hydraulic oil tank 80, thereby braking the winch during the no-load test. After the winch stops rotating, turn off the manual pump to complete the manual emergency debugging of the no-load test.

[0044] S2 performs electric emergency commissioning of the winch load test, including steps S2.1 to S2.4; S2.1 Hang a weight on the wire rope of the winch and start the oil pump unit again. The hydraulic oil of the oil pump unit flows to the oil inlet of the second multi-way valve 22. At the same time, the hydraulic oil of the second multi-way valve 22 flows to the hydraulic system and opens the winch brake through the brake oil circuit. S2.2 The process of driving the load to rise includes steps S2.2.1 to S2.2.2. S2.2.1 Adjust the valve core stroke screw in the second multi-way valve 22 to a preset stroke distance so that the hydraulic oil flows out of the oil outlet port D19 of the second multi-way valve 22 at the same flow rate. Adjust the pressure values ​​of the second relief valve and the third relief valve connected to the outside of the second multi-way valve 22 respectively. In this embodiment, the pressure value of the second relief valve is adjusted in the range of 26MPa~28MPa, and the pressure value of the third relief valve is adjusted in the range of 12MPa~14MPa. This allows the hydraulic oil entering the MWA interface of the hydraulic system to have different pressure values, so as to drive the winch to lift loads of different weights for load tests and observe whether there is any slippage. S2.2.2 Adjust the second and third relief valves to a preset fixed pressure value. In this embodiment, the pressure value of the second relief valve is 28 MPa and the pressure value of the third relief valve is 14 MPa. First, adjust the stroke distance of the valve core stroke screw in the second multi-way valve 22 to the maximum so that the hydraulic oil flow rate through the second multi-way valve 22 reaches the maximum, specifically 370 L / min. This allows the hydraulic oil to flow from the D19 interface of the second multi-way valve 22 to the MWA interface of the winch hydraulic system 3. Then, within the hydraulic oil flow rate range of 320 L / min to 370 L / min, by adjusting the stroke distance of the valve core stroke screw, the hydraulic oil flows out of the oil outlet interface D19 of the second multi-way valve 22 at different flow rates. This results in the hydraulic oil entering the MWA interface of the hydraulic system having different flow rates, thereby driving the winch to lift the same weight of load at different speeds for load testing and observing whether there is any slippage. S2.3 Repeat step S1.3, and then proceed to step S2.4; S2.4 During the winch's load operation, when the oil pump unit stops working, open the throttle valve NQ1 in the throttle circuit 4, turn the knob of the throttle valve NQ1 to the minimum value, switch the three-way ball valve T15 to the electric emergency state, start the electric emergency release pump H22, energize the emergency solenoid valve T17, and the emergency solenoid valve T17 reverses direction. Hydraulic oil enters through the emergency release pump H22 and the P valve port of the emergency solenoid valve T17, flows through the B valve port of the emergency solenoid valve T17, through the three-way ball valve T15, and then flows through the three-way ball valve T15 into the ball valve T16, and then into the throttle circuit 4 and the motor E port. Then adjust the knob of the throttle valve NQ1 to control the flow rate of hydraulic oil through the throttle circuit 4. The hydraulic oil flowing out of the motor F port merges with the hydraulic oil flowing through the throttle circuit 4 and flows into the four-way interface A02, and then into the shuttle valve 8. Pushing the shuttle valve 8, it flows into the reversing valve 5. The reversing valve 5 is switched to the left chamber, allowing hydraulic oil to enter the control end of the first brake 2. This releases the first brake 2, causing the winch to rotate and lower the load. After the load reaches the ground, the knob of the throttle valve NQ1 is adjusted to control the flow rate of hydraulic oil through the throttle circuit 4, reducing the flow rate. This causes the other circuit 9, connected to the throttle circuit 4, to move the shuttle valve 8, blocking the hydraulic oil flowing out of the four-way interface A02. At this time, the first brake 2, under the action of the spring, squeezes out the hydraulic oil and redirects it through the reversing valve 5 to the right chamber, flowing back to the hydraulic oil tank 80, thus braking the winch after the load has descended. When the load on the winch is lowered to the ground, the emergency solenoid valve T17 is closed, de-energizing the emergency solenoid valve group and ending the electric emergency state, completing the load test electric emergency debugging.

[0045] S2.5 Perform an electric emergency test on the second brake 33. Start the electric emergency release pump H22, and switch the emergency solenoid valve T17 to the left chamber. The hydraulic pressure from the emergency release pump H22 passes through the P valve port and then enters the T valve port of the first multi-way valve H19. Then, through the overflow valve, ball valve NV2, D8 interface, and ball valve BV2 / 4, it enters the control terminal of the second brake 33 to release the second brake 33, thereby verifying whether emergency braking can be performed by the second brake 33 under special circumstances.

[0046] During steps S2.2.1 to S2.2.2, the pressure of the hydraulic oil entering the second multi-way valve 22 can be adjusted by first adjusting the pressure value of the first relief valve. When the hydraulic oil flows out through the second multi-way valve 22, the hydraulic oil entering the winch hydraulic system 3 is partially depressurized through the second relief valve 6 to provide protection. At the same time, the pressure of the hydraulic oil entering the winch hydraulic system 3 is adjusted. After the hydraulic oil enters the winch hydraulic system 3 through the MWA interface, the brake circuit is first made to directly act on the brake of the hydraulic system 3, opening the winch brake. Then, the hydraulic oil drives the weight lifted by the winch to detach from the ground. Next, the hydraulic oil from the winch hydraulic system 3 flows back to the D20 port of the second multi-way valve 22 through the MWB interface. Then, the hydraulic oil flowing back to the second multi-way valve 22 is depressurized through the third relief valve 71 to prevent excessive pressure. Finally, the hydraulic oil flowing back to the second multi-way valve 22 flows back to the oil tank 80 through the D18 port of the second multi-way valve 22. The above process allows for load testing under different hydraulic oil flow rates and pressures, thereby determining whether the flow control and pressure control of the oil circuit meet the actual operating requirements.

Claims

1. A control method for emergency testing of cranes under different loads, implemented through a hydraulic control system, the hydraulic control system comprising an oil pump unit, a winch hydraulic system, a throttling oil circuit, a brake oil circuit, an electric emergency oil circuit, and a manual emergency oil circuit, characterized in that: Includes the following steps: S1 performs manual emergency testing of the winch under no-load conditions, including steps S1.1 to S1.2; S1.1 Adjust the pressure of the brake oil circuit to be equal to the pressure at the winch valve, start the oil pump unit, and let the hydraulic oil flow through the oil pump unit to the second multi-way valve and enter the hydraulic system of the winch. Then open the brake oil circuit in the oil storage state to release the winch brake and observe whether the winch rotates normally. S1.2 When the oil pump unit stops working during the winch's no-load state, open the manual pump in the manual emergency oil circuit. The oil in the tank enters the winch's hydraulic system through the manual emergency oil circuit and the throttling oil circuit. Adjust the throttling valve knob of the throttling oil circuit to gradually slow down the winch's rotation speed until the winch stops rotating. S2 performs an electric emergency test on the winch during the load test, including steps S2.1 to S2.2; S2.1 Hang a load on the wire rope of the winch, restart the oil pump unit, so that the hydraulic oil of the oil pump unit opens the winch brake after passing through the second multi-way valve. By adjusting the hydraulic oil pressure at the inlet and outlet of the second multi-way valve, different weight load tests are carried out. Then, while keeping the oil pressure constant, the hydraulic oil flow of the second multi-way valve is changed to drive different speeds to achieve load testing. S2.2 During the process of the winch being under load, the emergency solenoid valve in the electric emergency oil circuit is energized, and then the knob of the throttle valve is adjusted to control the descent speed of the load on the winch.

2. The control method for emergency testing of cranes under different loads according to claim 1, characterized in that: The oil pump unit is provided in two parts, and step S1.1 further includes: The brake oil circuit forms a branch circuit from the oil inlet port D5 of the second multi-way valve and connects to the MEP interface of the winch's hydraulic system, thereby opening the winch brake.

3. The control method for emergency testing of cranes under different loads according to claim 1, characterized in that: Step S1.1 further includes: The control handle drives the hydraulic circuit of the cab to connect with ports a1 and b1 of the second multi-way valve, pushing the valve core of the second multi-way valve to switch directions. After switching, the second relief valve and the third relief valve are adjusted to a preset fixed value. Then, the valve core stroke screw in the second multi-way valve is adjusted to a preset stroke distance so that the hydraulic oil at the oil outlet port D19 and the oil inlet port D20 of the second multi-way valve is fixed at the pressure and flow rate to the hydraulic system of the winch, thereby driving the winch to rotate at a constant speed. It is also convenient to change the pressure value of the second relief valve and the third relief valve and the stroke distance of the valve core stroke screw, thereby driving the winch to rotate at different speeds.

4. The control method for emergency testing of cranes under different loads according to claim 1, characterized in that: The oil pump unit includes two hydraulic pumps. The output end formed by the connection of the two hydraulic pumps is connected to the oil inlet interface D5 of the second multi-way valve. One end of the brake oil circuit is connected to the oil inlet interface D5 of the second multi-way valve, and the other end of the brake oil circuit is connected to the A20 interface. The A20 interface is connected to the MEP interface of the hydraulic system. The oil outlet of the second multi-way valve is provided with two interfaces, D18 and D19. The D18 interface is connected to the oil tank. The oil outlet interface D19 and the oil inlet interface D20 of the second multi-way valve are connected to the MWA interface and MWB interface of the hydraulic system, respectively.

5. The control method for emergency testing of cranes under different loads according to claim 1, characterized in that: The oil inlet port D5 of the second multi-way valve is connected to one end of the first relief valve, and the other end of the first relief valve is connected to the oil tank. The oil outlet port D19 of the second multi-way valve is connected to one end of the second relief valve, and the other end of the second relief valve is connected to the oil tank. The oil inlet port D20 of the second multi-way valve is connected to one end of the third relief valve, and the other end of the third relief valve is connected to the end of the second relief valve connected to the oil tank.

6. The control method for emergency testing of cranes under different loads according to claim 1, characterized in that: The brake fluid circuit includes a first shuttle valve, a second shuttle valve, and a pressure reducing valve T12. One end of the first shuttle valve is connected to the oil inlet interface D5 of the second multi-way valve, the other end of the first shuttle valve is connected to one end of the second shuttle valve, the other end of the second shuttle valve is connected to one end of the pressure reducing valve T12, and the other end of the pressure reducing valve T12 is connected to the A20 interface.

7. The control method for emergency testing of cranes under different loads according to claim 1, characterized in that: The electric emergency hydraulic circuit includes an electric emergency release pump and an emergency solenoid valve, while the manual emergency hydraulic circuit includes a three-way ball valve and a manual pump. One end of the ball valve is connected to the hydraulic oil tank, and the other end of the ball valve is connected to both the electric emergency release pump and the manual pump.

8. The control method for emergency testing of cranes under different loads according to claim 1, characterized in that: The P port of the emergency solenoid valve is connected to the electric emergency release pump, and the B port of the emergency solenoid valve is connected to one end of the three-way ball valve; the manual pump is connected to the other end of the three-way ball valve, the third end of the three-way ball valve is connected to one end of the ball valve, and the other end of the ball valve is connected to the hydraulic system of the winch.

9. The control method for emergency testing of cranes under different loads according to claim 1, characterized in that: One end of the ball valve four is connected to the D port of the first multi-way valve and one end of the reversing valve, respectively. The other end of the ball valve four is connected to one end of the throttling oil circuit and the E port of the motor connected to the winch, respectively. The other end of the throttling oil circuit is connected to one end of the four-way interface, the other end of the four-way interface is connected to the F port of the motor, the third end of the four-way interface is connected to one end of the shuttle valve, the other end of the shuttle valve is connected to one end of the reversing valve, the other end of the reversing valve is connected to the first brake, and the fourth end of the four-way interface is connected to the MWA interface in the hydraulic system of the winch.

10. The control method for emergency testing of cranes under different loads according to claim 1, characterized in that: The throttling oil circuit includes a throttling valve, a non-adjustable flow valve, and a ball valve five. The throttling valve, the non-adjustable flow valve, and the ball valve five are connected in series. The non-adjustable flow valve is connected to one end of the three-way interface, and the ball valve five is connected to the motor E port and the other end of the ball valve four.

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