A hydraulic control device and method for clamping mechanism

Abstract

The present invention belongs to the technical field of petroleum equipment control, and specifically provides a hydraulic control device and method for a clamping mechanism, comprising a plurality of clamping mechanisms, and also comprising a hydraulic oil pump unit, an oil return unit, a high-pressure pressure reducing unit, a low-pressure pressure reducing unit, a clamping mechanism control unit, a safety overflow unit, and an oil tank. The number of the hydraulic oil pump unit, the clamping mechanism control unit, and the clamping mechanism are all multiple, and the number of the clamping mechanism control unit and the clamping mechanism is the same, which solves the problem of multiple groups of support wheels and clamping mechanisms arranged in the axial direction of a steel pipe in the prior art, and the control of opening and clamping of the clamping mechanism and the synchronization of the multiple groups of clamping mechanisms will affect the straightness and ovality of the steel pipe quenching, and meets the requirements of the opening, clamping, and synchronous operation of the multiple groups of clamping mechanisms required by the steel pipe quenching process, and prevents the phenomenon of the steel pipe jumping out of the support wheel during quenching, reduces the defects on the outer surface of the steel pipe, and increases the yield rate of the steel pipe.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum equipment control, and in particular relates to a hydraulic control device and method for a clamping mechanism. Background Art

[0002] With the development of the steel pipe industry and the expansion of the scope of steel pipe use, the overall quenching of steel pipes not only requires higher mechanical properties, but also puts forward higher requirements for the straightness and ovality of the steel pipes after quenching. According to tests, rotating the steel pipe at a certain speed during quenching will improve the straightness and ovality of the steel pipe. The smaller the steel pipe specification, the greater the rotation speed, and the larger the specification, the lower the rotation speed.

[0003] In order to meet the rotation of the steel pipe during quenching and prevent the steel pipe from jumping out of the support wheel during high-speed rotation, a clamping mechanism is designed. Figure 2 As shown, it mainly includes support wheels, steel pipes, clamping arms and oil cylinders. The support wheels rotate, driving the steel pipes to rotate in the opposite direction. The clamping arms loosen and clamp the steel pipes under the drive of the oil cylinders. The length of the steel pipe is generally 6000mm to 146300mm. Multiple sets of support wheels and clamping mechanisms are arranged in the axial direction of the steel pipe. The opening and clamping control of the clamping mechanisms and the synchronization of multiple clamping mechanisms will affect the straightness and ovality of the steel pipe quenching.

[0004] In order to control the above clamping mechanisms, it is necessary to design a hydraulic control system to control multiple clamping mechanisms through an electrical control system to meet the requirements of opening, clamping and synchronous operation of multiple clamping mechanisms required by the steel pipe quenching process. Summary of the invention

[0005] The present invention provides a hydraulic control device and method for a clamping mechanism, the first purpose of which is to overcome the problem in the prior art that multiple groups of support wheels and clamping mechanisms are arranged in the axial direction of the steel pipe, the opening and clamping control of the clamping mechanisms, and the synchronization of multiple groups of clamping mechanisms will affect the straightness and ovality of the steel pipe quenching.

[0006] To this end, the present invention provides a hydraulic control device for a clamping mechanism, including multiple clamping mechanisms, each clamping mechanism including a supporting wheel, a steel pipe, a clamping arm, an oil cylinder, and a clamping wheel, the upper end of the clamping arm is connected to the oil cylinder, the lower end of the clamping arm is connected to the clamping wheel, the supporting wheel is connected to the steel pipe, the clamping wheel is in contact with and connected to the steel pipe and the clamping wheel is located above the steel pipe; it is characterized in that it also includes a hydraulic oil pump unit, an oil return unit, a high-pressure pressure reducing unit, a low-pressure pressure reducing unit, a clamping mechanism control unit, a safety overflow unit, and an oil tank, the number of the hydraulic oil pump unit, the clamping mechanism control unit and the clamping mechanism are all multiple, and the clamping mechanism control unit The number of the clamping mechanisms is the same as that of the clamping mechanisms, the inlet of each oil pump unit is connected to the outlet of the oil tank through an oil pipe, the outlet of each oil pump unit is respectively connected to the inlet of the high-pressure reducing unit and the inlet of the low-pressure reducing unit through oil pipes, the outlet of the high-pressure reducing unit is respectively connected to the inlet of each clamping mechanism control unit and the inlet of the safety overflow unit through oil pipes, the outlet of the low-pressure reducing unit is respectively connected to the inlet of each clamping mechanism control unit and the inlet of the safety overflow unit through oil pipes, the outlet of each clamping mechanism control unit is connected to an oil cylinder through an oil pipe, and the outlet of the safety overflow unit is connected to the inlet of the oil tank through an oil return unit.

[0007] The hydraulic oil pump unit includes an oil pump, a first solenoid valve, a relief valve and a pressure gauge. The oil tank is respectively connected to the inlet end of the oil pump and the inlet end of the first solenoid valve, the outlet end of the oil pump is respectively connected to the inlet of the high-pressure reducing unit and the inlet of the low-pressure reducing unit through the pressure gauge, and the outlet end of the first solenoid valve is respectively connected to the inlet of the high-pressure reducing unit and the inlet of the low-pressure reducing unit through the relief valve.

[0008] The hydraulic oil pump unit also includes a first one-way valve. The outlet end of the overflow valve and the outlet end of the pressure gauge are connected to the inlet end of the first one-way valve after merging through an oil pipe. The outlet end of the first one-way valve is respectively connected to the inlet of the high-pressure pressure reducing unit and the inlet of the low-pressure pressure reducing unit.

[0009] The high-pressure pressure reducing unit includes a first pressure reducing valve, a first pilot valve, and a first on-off valve, and the outlet end of the first one-way valve is connected to the first pressure reducing valve, the first pilot valve, and the first on-off valve in sequence; the low-pressure pressure reducing unit includes a second pressure reducing valve, a second pilot valve, and a second on-off valve, and the outlet end of the first one-way valve is connected to the second pressure reducing valve, the second pilot valve, and the second on-off valve in sequence.

[0010] The clamping mechanism control unit includes an electromagnetic control valve, a hydraulic lock, a throttle valve, and a valve. The first on-off valve is connected to the electromagnetic control valve, the hydraulic lock, the throttle valve, the valve and the cylinder in sequence, and the second on-off valve is connected to the electromagnetic control valve, the hydraulic lock, the throttle valve, the valve and the cylinder in sequence.

[0011] The safety overflow unit includes a second solenoid valve, a safety valve and a pressure sensor, the inlet end of the second solenoid valve is respectively connected to the first on-off valve and the second on-off valve, the outlet end of the second solenoid valve is connected to the oil return unit through the safety valve, and the safety valve is respectively connected to the first on-off valve and the second on-off valve.

[0012] The oil return unit comprises a second one-way valve and a filter, and the safety valve is connected to the second one-way valve, the filter and the inlet of the oil tank in sequence.

[0013] The oil pump adopts a constant pressure variable displacement pump.

[0014] The first on-off valve and the second on-off valve are both cartridge valves.

[0015] A hydraulic control method for a clamping mechanism comprises the following steps:

[0016] 1) When clamping is required, the first solenoid valve of the hydraulic oil pump unit is energized, the oil pump draws oil from the oil tank into the high-pressure pressure reducing unit, the high-pressure pressure reducing unit outputs high-pressure oil through the clamping mechanism control unit into the oil cylinder of the clamping mechanism, the oil cylinder causes the clamping arm to descend, thereby driving the clamping wheel to contact the outer surface of the steel pipe, and the high-pressure pressure reducing unit is closed; the low-pressure pressure reducing unit is opened, the oil pump draws oil from the oil tank into the low-pressure pressure reducing unit, the low-pressure pressure reducing unit outputs low-pressure oil through the clamping mechanism control unit into the oil cylinder of the clamping mechanism, and the oil cylinder causes the clamping wheel to press on the steel pipe; when the oil pressure exceeds the set value of the pressure sensor, the second solenoid valve is energized, and the oil flows into the oil tank through the second solenoid valve, the safety valve and the oil return unit in sequence;

[0017] 2) When releasing after clamping, the low-pressure pressure reducing unit is closed, the high-pressure pressure reducing unit is opened, the oil pump draws oil from the oil tank into the high-pressure pressure reducing unit, and the high-pressure pressure reducing unit outputs high-pressure oil through the clamping mechanism control unit into the oil cylinder of the clamping mechanism. The oil cylinder causes the clamping wheel to release the steel pipe, and the steel pipe rotates freely.

[0018] Beneficial effects of the present invention:

[0019] 1) In the hydraulic control device and method of the clamping mechanism of the present invention, each clamping mechanism is controlled by a separate clamping mechanism control unit. The throttle valve of the clamping mechanism control unit can ensure the synchronous operation of the clamping arms of the clamping mechanism, so that the entire length of the steel pipe can be clamped simultaneously during quenching, thereby ensuring the straightness of the steel pipe.

[0020] 2) The hydraulic control device and method of the clamping mechanism of the present invention switches between the high-pressure pressure reducing unit and the low-pressure pressure reducing unit to meet the requirements of the high pressure drop of the clamping cylinder, the low pressure is maintained after approaching the steel pipe, and the high pressure return can be achieved when returning.

[0021] 3) In the hydraulic control device and method of the clamping mechanism of the present invention, once the steel pipe bends during the quenching process, the bent steel pipe will react on the oil cylinder when rotating, and the pressure in the oil pipe will increase. When the oil source pressure exceeds the set value of the pressure sensor, the safety overflow unit will operate, and the energized oil source of the second solenoid valve will flow into the oil tank through the second solenoid valve and the safety valve. The oil source pressure is reduced to prevent the steel pipe from being crushed by the clamping mechanism, and at the same time, the equipment can be protected from overpressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described in detail below with reference to the accompanying drawings.

[0023] Figure 1 It is the structural principle diagram of the hydraulic control device of the clamping mechanism;

[0024] Figure 2 It is a simplified structural diagram of the clamping mechanism;

[0025] Figure 3 It is the structural principle diagram of the hydraulic oil pump unit;

[0026] Figure 4 It is the structural principle diagram of the high pressure reducing unit;

[0027] Figure 5 It is the structural principle diagram of the low-pressure pressure reducing unit;

[0028] Figure 6 It is a structural principle diagram of the clamping mechanism control unit;

[0029] Figure 7 It is the structural principle diagram of the oil return unit;

[0030] Figure 8 It is the structural principle diagram of the safety overflow unit.

[0031] Explanation of the reference numerals in the accompanying drawings: 1. Hydraulic oil pump unit; 2. Oil return unit; 3. High-pressure pressure reducing unit; 4. Low-pressure pressure reducing unit; 5. Clamping mechanism control unit; 6. Clamping mechanism; 7. Safety overflow unit; 8. Oil tank; 11. Oil pump; 12. First solenoid valve; 13. Overflow valve; 14. First non-return valve; 15. Pressure gauge; 21. Second non-return valve; 22. Filter; 31. First pressure reducing valve; 32. First pilot valve; 33. First on-off valve; 41. Second pressure reducing valve; 42. Second pilot valve; 43. Second on-off valve; 51. Solenoid control valve; 52. Hydraulic lock; 53. Throttle valve; 54. Valve; 61. Support wheel; 62. Steel pipe; 63. Clamping arm; 64. Oil cylinder; 65. Clamping wheel; 71. Second solenoid valve; 72. Safety valve; 73. Pressure sensor. DETAILED DESCRIPTION

[0032] Embodiment 1:

[0033] like Figure 1 and Figure 2 As shown, a clamping mechanism hydraulic control device includes multiple clamping mechanisms 6, each clamping mechanism 6 includes a support wheel 61, a steel pipe 62, a clamping arm 63, an oil cylinder 64, and a clamping wheel 65. The upper end of the clamping arm 63 is connected to the oil cylinder 64, and the lower end of the clamping arm 63 is connected to the clamping wheel 65. The support wheel 61 is connected to the steel pipe 62, and the clamping wheel 65 is in contact with the steel pipe 62 and is located above the steel pipe 62; it is characterized in that it also includes a hydraulic oil pump unit 1, an oil return unit 2, a high-pressure pressure reducing unit 3, a low-pressure pressure reducing unit 4, a clamping mechanism control unit 5, a safety overflow unit 7, and an oil tank 8, and the number of the hydraulic oil pump unit 1, the clamping mechanism control unit 5 and the clamping mechanism 6 are all multiple The number of clamping mechanism control units 5 and clamping mechanisms 6 is the same, the inlet of each oil pump unit 1 is connected to the outlet of the oil tank 8 through an oil pipe, the outlet of each oil pump unit 1 is respectively connected to the inlet of the high-pressure reducing unit 3 and the inlet of the low-pressure reducing unit 4 through an oil pipe, the outlet of the high-pressure reducing unit 3 is respectively connected to the inlet of each clamping mechanism control unit 5 and the inlet of the safety overflow unit 7 through an oil pipe, the outlet of the low-pressure reducing unit 4 is respectively connected to the inlet of each clamping mechanism control unit 5 and the inlet of the safety overflow unit 7 through an oil pipe, the outlet of each clamping mechanism control unit 5 is connected to an oil cylinder 64 through an oil pipe, and the outlet of the safety overflow unit 7 is connected to the inlet of the oil tank 8 through the oil return unit 2.

[0034] The working principle of the hydraulic control device of the clamping mechanism is:

[0035] 1) When clamping is required, that is, after receiving the clamping command from the PLC system, the first solenoid valve 12 of the hydraulic oil pump unit 1 is energized, and the oil pump 11 sucks oil from the oil tank 8 into the high-pressure pressure reducing unit 3. The high-pressure pressure reducing unit 3 outputs high-pressure oil into the oil cylinder 64 of the clamping mechanism 6 through the clamping mechanism control unit 5. Since the oil pressure required for the operation resistance of the oil cylinder 64 is high, the oil cylinder 64 causes the clamping arm 63 to descend, thereby driving the clamping wheel 65 to contact the outer surface of the steel pipe 62, and the high-pressure pressure reducing unit 3 is closed; low The high-pressure reducing unit 4 is opened, and the oil pump 11 sucks oil from the oil tank 8 into the low-pressure reducing unit 4. The low-pressure reducing unit 4 outputs low-pressure oil into the oil cylinder 64 of the clamping mechanism 6 through the clamping mechanism control unit 5. The oil cylinder 64 presses the clamping wheel 65 on the steel pipe 62, which prevents the steel pipe from jumping out of the support wheel during quenching and also prevents the clamping wheel from scratching the outer surface of the steel pipe. When the oil pressure exceeds the set value of the pressure sensor 73, the charged oil of the second solenoid valve 71 flows into the oil tank through the second solenoid valve 71, the safety valve 72 and the oil return unit 2 in sequence.

[0036] 2) When releasing after clamping is completed, that is, after clamping is completed, the PLC system issues a release command, the low-pressure pressure reducing unit 4 is closed, the high-pressure pressure reducing unit 3 is opened, the oil pump 11 draws oil from the oil tank 8 into the high-pressure pressure reducing unit 3, and the high-pressure pressure reducing unit 3 outputs high-pressure oil through the clamping mechanism control unit 5 into the oil cylinder 64 of the clamping mechanism 6, and the oil cylinder 64 causes the clamping wheel 65 to release the steel pipe 62, and the steel pipe 62 rotates freely.

[0037] Beneficial effects of the present invention:

[0038] 1) In the hydraulic control device and method for the clamping mechanism of the present invention, each clamping mechanism 6 is controlled by a separate clamping mechanism control unit 5. Through the throttle valve 53 of the clamping mechanism control unit 5, the clamping arm 63 of the clamping mechanism 6 can run synchronously, so that the entire length of the steel pipe 62 can be clamped simultaneously during quenching, thereby ensuring the straightness of the steel pipe.

[0039] 2) The hydraulic control device and method of the clamping mechanism of the present invention switches between the high-pressure pressure reducing unit and the low-pressure pressure reducing unit to meet the requirements of the high pressure drop of the clamping cylinder, the low pressure is maintained after approaching the steel pipe, and the high pressure return can be achieved when returning.

[0040] 3) In the hydraulic control device and method of the clamping mechanism of the present invention, during the quenching process, once the steel pipe 62 bends, the bent steel pipe 62 will react on the oil cylinder 64 when rotating, and the pressure in the oil pipe will increase. When the oil source pressure exceeds the set value of the pressure sensor 73, the safety overflow unit 7 works, and the second solenoid valve 71 charges the oil source through the second solenoid valve 71 and the safety valve 72 to flow into the oil tank 8. The oil source pressure is reduced to prevent the steel pipe 62 from being crushed by the clamping mechanism 6, and at the same time, the equipment can be protected from overpressure.

[0041] Embodiment 2:

[0042] like Figure 3 As shown, on the basis of Example 1, the hydraulic oil pump unit 1 includes an oil pump 11, a first solenoid valve 12, a relief valve 13 and a pressure gauge 15, the oil tank 8 is connected to the inlet end of the oil pump 11 and the inlet end of the first solenoid valve 12 respectively, the outlet end of the oil pump 11 is connected to the inlet of the high-pressure pressure reducing unit 3 and the inlet of the low-pressure pressure reducing unit 4 respectively through the pressure gauge 15, and the outlet end of the first solenoid valve 12 is connected to the inlet of the high-pressure pressure reducing unit 3 and the inlet of the low-pressure pressure reducing unit 4 respectively through the relief valve 13. The oil pressure output by the oil pump 11 is adjusted by adjusting the relief valve 13, and the on and off of the first solenoid valve 12 can realize whether the pressure oil enters the high-pressure pressure reducing unit 3 and the low-pressure pressure reducing unit 4.

[0043] The hydraulic oil pump unit 1 also includes a first one-way valve 14. The outlet end of the overflow valve 13 and the outlet end of the pressure gauge 15 are connected to the inlet end of the first one-way valve 14 after merging through an oil pipe. The outlet end of the first one-way valve 14 is respectively connected to the inlet of the high-pressure reducing unit 3 and the inlet of the low-pressure reducing unit 4; the setting of the first one-way valve 14 can prevent the impact of overpressure of the hydraulic control device of the clamping mechanism on the oil pump unit 1.

[0044] like Figure 4 and Figure 5 As shown, the high-pressure pressure reducing unit 3 includes a first pressure reducing valve 31, a first pilot valve 32, and a first on-off valve 33, and the outlet end of the first one-way valve 14 is connected to the first pressure reducing valve 31, the first pilot valve 32, and the first on-off valve 33 in sequence; the low-pressure pressure reducing unit 4 includes a second pressure reducing valve 41, a second pilot valve 42, and a second on-off valve 43, and the outlet end of the first one-way valve 14 is connected to the second pressure reducing valve 41, the second pilot valve 42, and the second on-off valve 43 in sequence. The first on-off valve 33 and the second on-off valve 43 meet the large flow of oil required by the oil cylinder 64 in the clamping mechanism 6; the first pilot valve 32 controls the opening of the first on-off valve 33, and the second pilot valve 42 controls the opening of the second on-off valve 43; the opening of the first pressure reducing valve 31 and the second pressure reducing valve 41 adjusts the oil pressure required by the clamping mechanism 6.

[0045] like Figure 6 As shown, the clamping mechanism control unit 5 includes an electromagnetic control valve 51, a hydraulic lock 52, a throttle valve 53, and a valve 54. The first on-off valve 33 is connected to the electromagnetic control valve 51, the hydraulic lock 52, the throttle valve 53, the valve 54, and the oil cylinder 64 in sequence. The second on-off valve 43 is connected to the electromagnetic control valve 51, the hydraulic lock 52, the throttle valve 53, the valve 54, and the oil cylinder 64 in sequence. The clamping mechanism control unit 5 corresponds to the clamping mechanism 6, and the number is consistent with the number of the clamping mechanism 6, so as to ensure that the steel pipe 62 jumps out of the support wheel 61 during rotary quenching; the oil flow returned by the hydraulic control device of the clamping mechanism is adjusted by adjusting the opening degree of the throttle valve 53. The control of the clamping mechanism control unit 5 adopts oil return throttling, so that back pressure will be generated when the clamping mechanism 6 is running, ensuring that the clamping mechanism 6 runs smoothly.

[0046] like Figure 8 As shown, the safety overflow unit 7 includes a second solenoid valve 71, a safety valve 72 and a pressure sensor 73. The inlet end of the second solenoid valve 71 is connected to the first on-off valve 33 and the second on-off valve 43 respectively, and the outlet end of the second solenoid valve 71 is connected to the oil return unit 2 through the safety valve 72. The safety valve 72 is connected to the first on-off valve 33 and the second on-off valve 43 respectively. When the oil pressure exceeds the set value of the pressure sensor 73, the charged oil of the second solenoid valve 71 flows into the oil tank 8 through the second solenoid valve 71 and the safety valve 72, and the oil pressure is reduced accordingly to prevent the steel pipe 62 from being crushed by the clamping mechanism 6, and at the same time, the hydraulic control device of the clamping mechanism can be protected from overpressure.

[0047] like Figure 7 As shown, the oil return unit 2 includes a second one-way valve 21 and a filter 22, and the safety valve 72 is sequentially connected to the second one-way valve 21, the filter 22 and the inlet of the oil tank 8. The second one-way valve 21 ensures that the return oil flows into the oil tank 8, and the filter 22 ensures the cleanliness of the oil in the hydraulic control device of the clamping mechanism.

[0048] The oil pump 11 adopts a constant pressure variable displacement pump, which has low noise, high speed, fast response speed, compact structure, high reliability, good repeatability, light weight and long service life.

[0049] The first on-off valve 33 and the second on-off valve 43 are both cartridge valves, which are small in size, low in cost, good in sealing, and can reduce installation time, leakage points, and maintenance time.

[0050] Embodiment 3:

[0051] A hydraulic control method for a clamping mechanism comprises the following steps:

[0052] 1) When clamping is required, the first solenoid valve 12 of the hydraulic oil pump unit 1 is energized, the oil pump 11 sucks oil from the oil tank 8 into the high-pressure pressure reducing unit 3, the high-pressure pressure reducing unit 3 outputs high-pressure oil through the clamping mechanism control unit 5 into the oil cylinder 64 of the clamping mechanism 6, the oil cylinder 64 causes the clamping arm 63 to descend, thereby driving the clamping wheel 65 to contact the outer surface of the steel pipe 62, and the high-pressure pressure reducing unit 3 is closed; the low-pressure pressure reducing unit 4 is opened, the oil pump 11 sucks oil from the oil tank 8 into the low-pressure pressure reducing unit 4, the low-pressure pressure reducing unit 4 outputs low-pressure oil through the clamping mechanism control unit 5 into the oil cylinder 64 of the clamping mechanism 6, and the oil cylinder 64 causes the clamping wheel 65 to press on the steel pipe 62; when the oil pressure exceeds the set value of the pressure sensor 73, the energized oil of the second solenoid valve 71 flows into the oil tank 8 through the second solenoid valve 71, the safety valve 72, the second one-way valve 21, and the filter 22 in sequence;

[0053] 2) When releasing after clamping is completed, the low-pressure pressure reducing unit 4 is closed, the high-pressure pressure reducing unit 3 is opened, the oil pump 11 sucks oil from the oil tank 8 into the high-pressure pressure reducing unit 3, and the high-pressure pressure reducing unit 3 outputs high-pressure oil into the oil cylinder 64 of the clamping mechanism 6 through the clamping mechanism control unit 5. The oil cylinder 64 causes the clamping wheel 65 to loosen the steel pipe 62, and the steel pipe 62 rotates freely.

[0054] In the clamping mechanism hydraulic control device and method of the present invention, each clamping mechanism 6 is controlled by a separate clamping mechanism control unit 5. Through the throttle valve 53 of the clamping mechanism control unit 5, the clamping arm 63 of the clamping mechanism 6 can be operated synchronously, and the full length of the steel pipe 62 can be clamped at the same time during quenching, thereby ensuring the straightness of the steel pipe, meeting the requirements of the opening, clamping and synchronous operation of multiple clamping mechanisms required by the steel pipe quenching process, preventing the steel pipe from jumping out of the support wheel during quenching, greatly reducing the defects on the outer surface of the steel pipe, and increasing the yield rate of the steel pipe; through the high-pressure pressure reducing unit The element switches to operate with the low-pressure reducing unit to meet the high-pressure drop of the clamping cylinder. The low pressure is maintained after approaching the steel pipe, and the return can achieve high-pressure return; during the quenching process, once the steel pipe 62 bends, the bent steel pipe 62 will react on the cylinder 64 when rotating, and the pressure in the oil pipe will increase. When the oil source pressure exceeds the set value of the pressure sensor 73, the safety overflow unit 7 works, and the second solenoid valve 71 charges the oil source through the second solenoid valve 71 and the safety valve 72 to flow into the oil tank 8. The oil source pressure is reduced to prevent the steel pipe 62 from being crushed by the clamping mechanism 6, and the equipment can be protected from overpressure at the same time.

[0055] In the description of the present invention, it should be understood that if a term indicates an orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on this patent.

[0056] The above examples are merely illustrative of the present invention and do not constitute a limitation on the protection scope of the present invention. All designs that are the same or similar to the present invention fall within the protection scope of the present invention.

Claims

1. A hydraulic control method for a clamping mechanism, characterized in that: The control is performed based on a clamping mechanism hydraulic control device, the clamping mechanism hydraulic control device comprising a plurality of clamping mechanisms (6), a hydraulic oil pump unit (1), an oil return unit (2), a high-pressure decompression unit (3), a low-pressure decompression unit (4), a clamping mechanism control unit (5), a safety overflow unit (7) and an oil tank (8), each clamping mechanism (6) comprising a support wheel (61), a steel pipe (62), a clamping arm (63), an oil cylinder (64), and a clamping wheel (65), the upper end of the clamping arm (63) being connected to the oil cylinder (64), the lower end of the clamping arm (63) being connected to the clamping wheel (65), the upper end of the support wheel (61) being connected to the steel pipe (62), the clamping wheel (65) being in contact with and connected to the steel pipe (62), and the clamping wheel (65) being located above the steel pipe (62); the hydraulic oil pump unit (1), the clamping mechanism control unit (5) and the clamping mechanism The number of the clamping mechanisms (6) is multiple, the number of the clamping mechanism control units (5) and the number of the clamping mechanisms (6) are the same, the inlet of the oil pump unit (1) is connected to the outlet of the oil tank (8) through an oil pipe, the outlet of the oil pump unit (1) is respectively connected to the inlet of the high-pressure pressure reducing unit (3) and the inlet of the low-pressure pressure reducing unit (4) through oil pipes, the outlet of the high-pressure pressure reducing unit (3) is respectively connected to the inlet of each clamping mechanism control unit (5) and the inlet of the safety overflow unit (7) through oil pipes, the outlet of the low-pressure pressure reducing unit (4) is respectively connected to the inlet of each clamping mechanism control unit (5) and the inlet of the safety overflow unit (7) through oil pipes, the outlet of each clamping mechanism control unit (5) is connected to an oil cylinder (64) through an oil pipe, and the outlet of the safety overflow unit (7) is connected to the inlet of the oil tank (8) through an oil return unit (2); The clamping mechanism hydraulic control method comprises the following steps: 1) When clamping is required, the first solenoid valve (12) of the hydraulic oil pump unit (1) is energized, the oil pump (11) draws oil from the oil tank (8) into the high-pressure pressure reducing unit (3), the high-pressure pressure reducing unit (3) outputs high-pressure oil into the oil cylinder (64) of the clamping mechanism (6) through the clamping mechanism control unit (5), the oil cylinder (64) causes the clamping arm (63) to descend, thereby driving the clamping wheel (65) to contact the outer surface of the steel pipe (62), and the high-pressure pressure reducing unit (3) is closed; the low-pressure pressure reducing unit ( 4) is opened, the oil pump (11) sucks oil from the oil tank (8) into the low-pressure pressure reducing unit (4), the low-pressure pressure reducing unit (4) outputs low-pressure oil into the oil cylinder (64) of the clamping mechanism (6) through the clamping mechanism control unit (5), and the oil cylinder (64) presses the clamping wheel (65) onto the steel pipe (62); when the oil pressure exceeds the set value of the pressure sensor (73), the charged oil of the second solenoid valve (71) flows into the oil tank (8) through the second solenoid valve (71), the safety valve (72) and the oil return unit (2) in sequence; 2) When releasing after the clamping is completed, the low-pressure pressure reducing unit (4) is closed, the high-pressure pressure reducing unit (3) is opened, the oil pump (11) sucks oil from the oil tank (8) into the high-pressure pressure reducing unit (3), the high-pressure pressure reducing unit (3) outputs high-pressure oil into the oil cylinder (64) of the clamping mechanism (6) through the clamping mechanism control unit (5), and the oil cylinder (64) causes the clamping wheel (65) to release the steel pipe (62), so that the steel pipe (62) rotates freely.

2. The hydraulic control method of the clamping mechanism according to claim 1, characterized in that: The hydraulic oil pump unit (1) comprises an oil pump (11), a first solenoid valve (12), a relief valve (13) and a pressure gauge (15); the oil tank (8) is respectively connected to the inlet end of the oil pump (11) and the inlet end of the first solenoid valve (12); the outlet end of the oil pump (11) is respectively connected to the inlet of the high-pressure pressure reducing unit (3) and the inlet of the low-pressure pressure reducing unit (4) via the pressure gauge (15); the outlet end of the first solenoid valve (12) is respectively connected to the inlet of the high-pressure pressure reducing unit (3) and the inlet of the low-pressure pressure reducing unit (4) via the relief valve (13).

3. The hydraulic control method of the clamping mechanism according to claim 2, characterized in that: The hydraulic oil pump unit (1) further comprises a first one-way valve (14); the outlet end of the overflow valve (13) and the outlet end of the pressure gauge (15) are connected to the inlet end of the first one-way valve (14) after merging through an oil pipe; the outlet end of the first one-way valve (14) is respectively connected to the inlet of the high-pressure pressure reducing unit (3) and the inlet of the low-pressure pressure reducing unit (4).

4. The hydraulic control method of the clamping mechanism according to claim 3, characterized in that: The high-pressure pressure reducing unit (3) comprises a first pressure reducing valve (31), a first pilot valve (32), and a first on-off valve (33), and the outlet end of the first one-way valve (14) is connected to the first pressure reducing valve (31), the first pilot valve (32), and the first on-off valve (33) in sequence; the low-pressure pressure reducing unit (4) comprises a second pressure reducing valve (41), a second pilot valve (42), and a second on-off valve (43), and the outlet end of the first one-way valve (14) is connected to the second pressure reducing valve (41), the second pilot valve (42), and the second on-off valve (43) in sequence.

5. The hydraulic control method of the clamping mechanism according to claim 4, characterized in that: The clamping mechanism control unit (5) comprises an electromagnetic control valve (51), a hydraulic lock (52), a throttle valve (53), and a valve (54); the first on-off valve (33) is sequentially connected to the electromagnetic control valve (51), the hydraulic lock (52), the throttle valve (53), the valve (54), and the oil cylinder (64); and the second on-off valve (43) is sequentially connected to the electromagnetic control valve (51), the hydraulic lock (52), the throttle valve (53), the valve (54), and the oil cylinder (64).

6. The hydraulic control method of the clamping mechanism according to claim 4, characterized in that: The safety overflow unit (7) comprises a second solenoid valve (71), a safety valve (72) and a pressure sensor (73); the inlet end of the second solenoid valve (71) is respectively connected to the first on-off valve (33) and the second on-off valve (43); the outlet end of the second solenoid valve (71) is connected to the oil return unit (2) via the safety valve (72); and the safety valve (72) is respectively connected to the first on-off valve (33) and the second on-off valve (43).

7. The hydraulic control method of the clamping mechanism according to claim 6, characterized in that: The oil return unit (2) comprises a second one-way valve (21) and a filter (22), and the safety valve (72) is connected to the second one-way valve (21), the filter (22) and the inlet of the oil tank (8) in sequence.

8. The hydraulic control method of the clamping mechanism according to claim 2, characterized in that: The oil pump (11) is a constant pressure variable displacement pump.

9. The hydraulic control method of the clamping mechanism according to claim 6, characterized in that: The first on-off valve (33) and the second on-off valve (43) are both cartridge valves.

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