A clamping cylinder pressurization and decompression switching circuit and its switching method

Abstract

The present invention provides a clamping cylinder pressurization and depressurization switching circuit and its method, including the following steps: Step S001: Adjust the first pressure reducing valve to the required high pressure and the second pressure reducing valve to the required low pressure; Step S002: When starting the clamping cylinder, make the first pilot valve in a cut-off state and the second pilot valve in a conducting state. At this time, the first pressure reducing valve is in communication with the first on-off valve, and the clamping cylinder operates at high pressure; Step S003: After the clamping cylinder is in the clamping state, make the first pilot valve in a conducting state and the second pilot valve in a cut-off state. At this time, the second pressure reducing valve is in communication with the second on-off valve, and the clamping cylinder maintains a low pressure. The clamping cylinder pressurization and depressurization switching circuit and its switching method of the present invention can switch the clamping cylinder between the high-pressure operating state and the low-pressure holding state, prevent the steel pipe from jumping out of the support wheel during quenching, solve the problem of bruising and scratching the outer surface of the steel pipe, reduce the defects on the outer surface of the steel pipe, and increase the yield of the steel pipe.

Description

Technical Field

[0001] The present invention belongs to the technical field related to the pressing of steel pipe quenching equipment, and particularly relates to a clamping cylinder pressurization and decompression switching circuit and a switching method thereof. Background Art

[0002] The straightness of the overall quenching of a steel pipe is the main parameter for evaluating the success or failure of the quenching process. Experiments have proved that rotating the steel pipe at a certain speed during quenching will greatly increase the straightness of the steel pipe. The steel pipe rotates on the support wheels and is particularly prone to jumping out of the rotating device when rotating at high speed. In order to prevent the steel pipe from jumping out during the quenching process and to ensure the straightness of the steel pipe, the steel pipe needs to be clamped during the high-speed rotation process. And the magnitude of the clamping force will affect the surface quality of the steel pipe. If the clamping force is too large, it will inevitably increase the rotation resistance, and will also damage and scratch the outer surface of the steel pipe, causing defects on the outer surface of the steel pipe and affecting the yield of the steel pipe; if the clamping force is too small, it will be difficult to clamp the steel pipe, and the steel pipe will jump out of the support wheels. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a clamping cylinder pressurization and decompression switching circuit and a switching method thereof, which are used to overcome the above problems or at least partially solve or alleviate the above problems.

[0004] The present invention provides a clamping cylinder pressurization and decompression switching circuit, comprising:

[0005] A high-pressure medium circuit, one end of the high-pressure medium circuit is connected to an oil pump, and the other end is connected in parallel with a first pressure reducing valve and a second pressure reducing valve, and the pressure regulation magnitudes of the first pressure reducing valve and the second pressure reducing valve are different;

[0006] A first pilot valve and a second pilot valve, the inlet of the first pilot valve is communicated with the outlet of the first pressure reducing valve, and the inlet of the second pilot valve is communicated with the outlet of the second pressure reducing valve;

[0007] A first on-off valve and a second on-off valve, the housings of the first on-off valve and the second on-off valve are respectively provided with an inlet, a control port and an outlet. The control port on the first on-off valve is communicated with the outlet of the first pilot valve, and the inlet on the first on-off valve is communicated with the outlet of the first pressure reducing valve; the control port on the second on-off valve is communicated with the outlet of the second pilot valve, and the inlet on the second on-off valve is communicated with the outlet of the first pressure reducing valve;

[0008] A low-pressure medium circuit, one end of the low-pressure medium circuit is respectively connected to the outlet of the first on-off valve and the outlet of the second on-off valve, and the other end is connected to the inlet of the clamping cylinder;

[0009] An oil return pipeline, the oil return pipeline is communicated with the outlet of the clamping cylinder.

[0010] The present invention also has the following optional features.

[0011] Optionally, the first on-off valve and the second on-off valve are large-diameter cartridge valves.

[0012] Optionally, the first pressure reducing valve and the second pressure reducing valve are manually adjustable valves.

[0013] Optionally, the first pilot valve and the second pilot valve are two-position four-way valves, which are in the conducting state in the initial state and in the cut-off state in the switching state.

[0014] Optionally, the first pilot valve and the second pilot valve are two-position four-way solenoid valves, which are in the conducting state in the power-off state and in the cut-off state in the power-on state.

[0015] Optionally, a first check valve is further connected between the outlet of the first pressure reducing valve and the inlet of the first pilot valve; a second check valve is further connected between the outlet of the second pressure reducing valve and the inlet of the second pilot valve.

[0016] Optionally, the high-pressure medium circuit, the low-pressure medium circuit, the first on-off valve and the second on-off valve are all integrated in a valve block.

[0017] The present invention also provides a method for switching the pressurization and pressure reduction of a clamping cylinder, which is implemented by using the clamping cylinder pressurization and pressure reduction switching circuit described in any one of the above, and includes the following steps:

[0018] Step S001: Adjust the first pressure reducing valve to the required high pressure and the second pressure reducing valve to the required low pressure;

[0019] Step S002: When it is necessary to start the clamping cylinder, make the first pilot valve in the cut-off state and the second pilot valve in the conducting state. At this time, the first pressure reducing valve is in communication with the first on-off valve, and the clamping cylinder operates at high pressure;

[0020] Step S003: After the clamping cylinder is in the clamping state, make the first pilot valve in the conducting state and the second pilot valve in the cut-off state. At this time, the second pressure reducing valve is in communication with the second on-off valve, and the clamping cylinder maintains low pressure.

[0021] The clamping cylinder pressurization and decompression switching circuit and its switching method of the present invention control the conduction or truncation of the first pilot valve and the second pilot valve, thereby switching the low-pressure medium circuit to be connected to the first on-off valve or the second on-off valve, and further enabling the high-pressure medium circuit to be connected to the low-pressure medium circuit through the first pressure reducing valve or the second pressure reducing valve, ensuring that the required pressure medium enters the low-pressure medium circuit, realizing that the high-pressure medium enters the low-pressure medium circuit after decompression, and controlling the pressure of the clamping cylinder. Through such circuit control, the clamping cylinder can achieve "high-pressure operation and low-pressure maintenance", prevent the phenomenon of the steel pipe jumping out of the supporting wheel during quenching, solve the problem of bruising and scratching the outer surface of the steel pipe, reduce the defects on the outer surface of the steel pipe, increase the yield of the steel pipe, and ensure the smooth implementation of the steel pipe quenching process. Brief Description of the Drawings

[0022] Figure 1 is a schematic structural diagram of the clamping cylinder pressurization and decompression switching circuit of the present invention.

[0023] In the above figures: 1 high-pressure medium circuit; 2 first pressure reducing valve; 3 second pressure reducing valve; 4 first pilot valve; 5 second pilot valve; 6 first on-off valve; 7 second on-off valve; 8 low-pressure medium circuit; 9 oil return pipeline; 10 first check valve; 11 second check valve; 12 valve block.

[0024] The present invention will be further described in detail below with reference to the drawings and embodiments. Detailed Embodiment

[0025] Embodiment 1

[0026] Refer to Figure 1 , the embodiment of the present invention proposes a clamping cylinder pressurization and decompression switching circuit, including: a high-pressure medium circuit 1, a first pilot valve 4 and a second pilot valve 5, a first on-off valve 6 and a second on-off valve 7, a low-pressure medium circuit 8 and an oil return pipeline 9; one end of the high-pressure medium circuit 1 is connected to an oil pump, and the other end is connected in parallel with a first pressure reducing valve 2 and a second pressure reducing valve 3, and the pressure regulation magnitudes of the first pressure reducing valve 2 and the second pressure reducing valve 3 are different; the inlet of the first pilot valve 4 is connected to the outlet of the first pressure reducing valve 2, and the inlet of the second pilot valve 5 is connected to the outlet of the second pressure reducing valve 3; the housing of the first on-off valve 6 and the second on-off valve 7 are respectively provided with an inlet, a control port and an outlet, the control port on the first on-off valve 6 is connected to the outlet of the first pilot valve 4, and the inlet on the first on-off valve 6 is connected to the outlet of the first pressure reducing valve 2; the control port on the second on-off valve 7 is connected to the outlet of the second pilot valve 5, and the inlet on the second on-off valve 7 is connected to the outlet of the first pressure reducing valve 3; one end of the low-pressure medium circuit 8 is respectively connected to the outlet of the first on-off valve 6 and the outlet of the second on-off valve 7, and the other end is connected to the inlet of the clamping cylinder; the oil return pipeline 9 is connected to the outlet of the clamping cylinder;

[0027] Before use, one end of the oil pump of the pump station is connected to one end of the high-pressure medium circuit through a hydraulic pipeline, one end of the low-pressure medium circuit is connected to the hydraulic inlet of the clamping cylinder through a hydraulic pipeline, and the hydraulic outlet of the clamping cylinder is connected to the oil tank of the pump station through an oil return pipeline; during use, first adjust the first pressure reducing valve 2 to the required high pressure and the second pressure reducing valve 3 to the required low pressure; at this time, control the conduction and cutoff of the first pilot valve 4 and the second pilot valve 5.

[0028] When the outlet of the first pilot valve 4 is in conduction with the control port of the first on-off valve 6, the inlet and outlet of the first control valve 6 are cut off; when the outlet of the first pilot valve 4 is cut off from the control port of the first on-off valve 6, the inlet and outlet of the first on-off valve 6 are in conduction; when the outlet of the second pilot valve 5 is in conduction with the control port of the second on-off valve 7, the inlet and outlet of the second on-off valve 7 are cut off, and when the outlet of the second pilot valve 5 is cut off from the control port of the second on-off valve 7, the inlet and outlet of the second on-off valve 7 are in conduction.

[0029] According to the above rules, when it is necessary to start the clamping cylinder, make the first pilot valve 4 in the cutoff state and the second pilot valve 5 in the conduction state. At this time, the first pressure reducing valve 2 and the first on-off valve 6 are in conduction, and at this time, the clamping cylinder operates at high pressure to clamp the steel pipe; after the clamping cylinder clamps the steel pipe, make the first pilot valve 4 in the conduction state and the second pilot valve 5 in the cutoff state. At this time, the second pressure reducing valve 3 and the second on-off valve 7 are in conduction, and at this time, the clamping cylinder maintains low pressure. In this way, it can not only prevent the phenomenon that the steel pipe jumps out of the supporting wheel during quenching, but also avoid the clamping cylinder from scratching or damaging the outer surface of the steel pipe, reduce the defects on the outer surface of the steel pipe, and increase the yield rate of the steel pipe.

[0030] Embodiment 2

[0031] Reference Figure 1 , on the basis of Embodiment 1, the first on-off valve 6 and the second on-off valve 7 are large-diameter cartridge valves.

[0032] The cartridge valve itself has an inlet, a control port and an outlet. After supplying pressure to the control port, the conduction between the inlet and the outlet will be cut off. After the control port is depressurized, supplying pressure to the inlet can make the inlet and the outlet in conduction. The first on-off valve 6 and the second on-off valve 7 using large-diameter cartridge valves can meet the requirements of switching the pressurization and depressurization of the clamping cylinder.

[0033] Embodiment 3

[0034] Reference Figure 1 , on the basis of Embodiment 2, the first pressure reducing valve 2 and the second pressure reducing valve 3 are manual regulating valves.

[0035] Manually adjusting the first pressure reducing valve 2 and the second pressure reducing valve 3 has pressure stability and can greatly enhance the anti-pollution ability of the circuit.

[0036] Example 4

[0037] Reference Figure 1 , on the basis of Example 1 or 3, the first pilot valve 4 and the second pilot valve 5 are two-position four-way valves, which are in the conducting state in the initial state and in the cut-off state in the switching state.

[0038] In the initial state, the first pilot valve 4 and the second pilot valve 5 are in the conducting state, that is, they supply pressure to the control ports of the first on-off valve 6 and the second on-off valve 7 respectively, so that the inlets and outlets of the first on-off valve 6 and the second on-off valve 7 are both in the cut-off state. At this time, the clamping cylinder is not started. After switching the state of one of the first pilot valve 4 and the second pilot valve 5, the clamping cylinder starts to clamp at the pressure corresponding to the first pressure reducing valve 2 or the second pressure reducing valve 3 corresponding to the switched first pilot valve 4 or second pilot valve 5.

[0039] Example 5

[0040] Reference Figure 1 , on the basis of Example 4, the first pilot valve 4 and the second pilot valve 5 are two-position four-way solenoid valves, which are in the conducting state in the power-off state and in the cut-off state in the power-on state.

[0041] The first pilot valve 4 and the second pilot valve 5 adopt solenoid valves, and a controller such as a PLC can be used to control them to make them automated or semi-automated.

[0042] Example 6

[0043] Reference Figure 1 , on the basis of Example 1 or 5, a first check valve 10 is further connected between the outlet of the first pressure reducing valve 2 and the inlet of the first pilot valve 4; a second check valve 11 is further connected between the outlet of the second pressure reducing valve 3 and the inlet of the second pilot valve 5.

[0044] The first check valve 10 and the second check valve 11 can respectively prevent the hydraulic oil from flowing back from the inlets of the first pilot valve 4 and the second pilot valve 5 to the hydraulic pipelines connected thereto.

[0045] Example 7

[0046] Reference Figure 1 , on the basis of Example 1 or 6, the high-pressure medium circuit 1, the low-pressure medium circuit 9, the first on-off valve 6 and the second on-off valve 7 are all integrated in a valve block 12.

[0047] The high-pressure medium circuit 1 and the low-pressure medium circuit 9 can directly be the hydraulic oil channels in the valve block 12, and the valve block 12 can also directly serve as the valve body of the first on-off valve 6 and the second on-off valve 7.

[0048] Example 8

[0049] The implementation of the present invention proposes a method for switching the pressurization and decompression of a clamping cylinder, which is implemented by using the clamping cylinder pressurization and decompression switching circuit described in any of the above embodiments, and includes the following steps: Step S001: Adjust the first pressure reducing valve 2 to the required high pressure, and adjust the second pressure reducing valve 3 to the required low pressure; Step S002: When it is necessary to start the clamping cylinder, make the first pilot valve 4 in a cut-off state and the second pilot valve 5 in a conducting state. At this time, the first pressure reducing valve 2 is in communication with the first on-off valve 6, and the clamping cylinder operates at high pressure; Step S003: After the clamping cylinder is in the clamping state, make the first pilot valve 4 in a conducting state and the second pilot valve 5 in a cut-off state. At this time, the second pressure reducing valve 3 is in communication with the second on-off valve 7, and the clamping cylinder maintains a low pressure.

[0050] In step S001, the high pressure adjusted by the first pressure reducing valve 2 is the operating pressure for the clamping cylinder to start clamping the steel pipe, and the low pressure adjusted by the second pressure reducing valve 3 is the holding pressure after the clamping cylinder clamps the steel pipe;

[0051] In step S002, make the first pilot valve 4 switch to the cut-off state and the second pilot valve 5 remain in the conducting state. At this time, the control port of the first on-off valve 6 loses pressure, and the inlet and outlet of the first on-off valve 6 can be conducted under pressure. The control port of the second on-off valve 7 is supplied with pressure and cannot be conducted. Therefore, the inlet and outlet of the second on-off valve 7 are cut off. In this way, the hydraulic oil in the high-pressure medium circuit 1 passes through the first pressure reducing valve 2 and then through the first on-off valve 6 into the low-pressure medium circuit 8, and finally enters the inlet of the clamping cylinder, making the clamping cylinder operate at high pressure;

[0052] In step S003, make the second pilot valve 5 switch to the cut-off state and the first pilot valve 4 switch to the conducting state. At this time, the control port of the second on-off valve 7 loses pressure, and the inlet and outlet of the second on-off valve 7 can be conducted under pressure. The control port of the first on-off valve 6 is supplied with pressure and cannot be conducted. Therefore, the inlet and outlet of the first on-off valve 6 are cut off. In this way, the hydraulic oil in the high-pressure medium circuit 1 passes through the second pressure reducing valve 3 and then through the second on-off valve 7 into the low-pressure medium circuit 8, and finally enters the inlet of the clamping cylinder, making the clamping cylinder maintain a low-pressure clamping state.

[0053] As described above, it is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any change or replacement that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims. The components and structures not described in detail in this embodiment are well-known components and common structures or common means in this industry, and will not be described one by one here.

Claims

1. A clamping cylinder pressurization and depressurization switching circuit, characterized in that, Comprising: A high-pressure medium circuit (1), one end of the high-pressure medium circuit (1) is connected to an oil pump, and the other end is connected in parallel with a first pressure reducing valve (2) and a second pressure reducing valve (3), and the pressure regulation magnitudes of the first pressure reducing valve (2) and the second pressure reducing valve (3) are different; A first pilot valve (4) and a second pilot valve (5), an inlet of the first pilot valve (4) is communicated with an outlet of the first pressure reducing valve (2), and an inlet of the second pilot valve (5) is communicated with an outlet of the second pressure reducing valve (3); A first on-off valve (6) and a second on-off valve (7), inlets, control ports and outlets are respectively arranged on the housings of the first on-off valve (6) and the second on-off valve (7), the control port on the first on-off valve (6) is communicated with an outlet of the first pilot valve (4), and the inlet on the first on-off valve (6) is communicated with the outlet of the first pressure reducing valve (2); The control port on the second on-off valve (7) is communicated with an outlet of the second pilot valve (5), and the inlet on the second on-off valve (7) is communicated with the outlet of the first pressure reducing valve (3); A low-pressure medium circuit (8), one end of the low-pressure medium circuit (8) is respectively connected to the outlets of the first on-off valve (6) and the second on-off valve (7), and the other end is communicated with an inlet of a clamping cylinder; An oil return pipeline (9), the oil return pipeline (9) is communicated with an outlet of the clamping cylinder; The first pilot valve (4) and the second pilot valve (5) are two-position four-way valves, and are in a conducting state in an initial state and in a cut-off state in a switching state; A first check valve (10) is further connected between the outlet of the first pressure reducing valve (2) and the inlet of the first pilot valve (4); A second check valve (11) is further connected between the outlet of the second pressure reducing valve (3) and the inlet of the second pilot valve (5); The high-pressure medium circuit (1), the low-pressure medium circuit (9), the first on-off valve (6) and the second on-off valve (7) are all integrated in a valve block (12).

2. The clamping cylinder pressurization and depressurization switching circuit according to claim 1, characterized in that, The first on-off valve (6) and the second on-off valve (7) are large-diameter cartridge valves.

3. The clamping cylinder pressurization and depressurization switching circuit according to claim 1, characterized in that, The first pressure reducing valve (2) and the second pressure reducing valve (3) are manually adjustable valves.

4. The clamping cylinder pressurization and depressurization switching circuit according to claim 1, characterized in that, The first pilot valve (4) and the second pilot valve (5) are two-position four-way solenoid valves, and are in a conducting state in a power-off state and in a cut-off state in a power-on state.

5. A clamping cylinder pressurization and depressurization switching method, implemented using the clamping cylinder pressurization and depressurization switching circuit according to any one of claims 1 to 4, characterized in that, Including the following steps: Step S001: Adjust the first pressure reducing valve (2) to a required high pressure and adjust the second pressure reducing valve (3) to a required low pressure; Step S002: When it is necessary to start the clamping cylinder, make the first pilot valve (4) in a cut-off state and make the second pilot valve (5) in a conducting state. At this time, the first pressure reducing valve (2) is conducted with the first on-off valve (6), and at this time, the clamping cylinder operates at high pressure; Step S003: After the clamping cylinder is in a clamping state, make the first pilot valve (4) in a conducting state and make the second pilot valve (5) in a cut-off state. At this time, the second pressure reducing valve (3) is conducted with the second on-off valve (7), and at this time, the clamping cylinder maintains a low pressure.

Images