A hydraulic control system and control method for a mandrel support frame adjustment device

Abstract

The present invention discloses a hydraulic control system and a control method for a mandrel support adjusting device. The system includes: a pressure reducing valve, a first hydraulic control check valve, a second hydraulic control check valve, a third hydraulic control check valve, a two-position four-way electromagnetic directional control valve, a three-position four-way high-frequency response proportional directional control valve, an adjusting hydraulic cylinder, and an opening hydraulic cylinder. In the present invention, by filling the rodless cavity of the adjusting hydraulic cylinder with hydraulic oil, when the opening hydraulic cylinder acts on the piston rod of the adjusting hydraulic cylinder, the hydraulic oil in the rodless cavity can be used as a hydraulic spring to absorb the impact, and can buffer the transient force generated when the mandrel roller opens and closes. Compared with the prior art, it effectively solves the problem of the cracking of the lift base caused by using a worm and screw lift for adjustment and positioning. Moreover, the hydraulic control system of the mandrel support adjusting device has a low failure rate, a compact structure, a low equipment maintenance cost, can improve the service life of the entire device, and improve production efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of rolling mill control, and particularly to a hydraulic control system and a control method for a mandrel support adjusting device. Background Art

[0002] Rolling mill machinery and equipment, especially the continuous rolling mill in hot-rolled seamless steel pipe production equipment, is the most widely used longitudinal rolling forming equipment today. During the process of rolling steel pipes, the rolls and the mandrel on the continuous rolling mill can form a fixed pass. The rolls will transmit a huge rolling force to the mandrel through the rolled piece. Therefore, the stability of the mandrel during the steel pipe rolling process directly affects the wall thickness accuracy of the finished pipe. That is to say, the stability of the mandrel has an important impact on the quality of the finished pipe and the productivity of the entire unit. In actual production, different steel pipes require different mandrels. After replacing mandrels of different specifications according to the requirements of the steel pipe rolling process, the position of the mandrel support must be adjusted accordingly to ensure that the mandrel is in the correct position. Currently, the position of the mandrel support is mainly adjusted through a mandrel support adjusting device to ensure the stability of the mandrel during the rolling process.

[0003] In the prior art, the mandrel support adjusting device includes a lifting motor and a worm gear screw jack. The base of the worm gear screw jack is fixed on the rolling mill frame, and the lifting motor can drive the screw of the worm gear screw jack to move. After the position of the mandrel support is adjusted, the mandrel support, the opening hydraulic cylinder and the closing hydraulic cylinder that can drive the mandrel support to move, and the mandrel roller cooperate to complete the steel pipe rolling process. Among them, the opening hydraulic cylinder can drive the mandrel roller to open, and the closing hydraulic cylinder can drive the mandrel roller to close. During the rolling process, the opening hydraulic cylinder and the closing hydraulic cylinder can indirectly adjust the opening and closing state of the mandrel roller by controlling the swing of the swing arm. Among them, the moving stroke of the piston rod of the opening hydraulic cylinder is limited by the screw of the worm gear screw jack, thereby finally realizing the control of the opening size of the mandrel support.

[0004] However, during the rolling process, due to the high rolling speed, before the mandrel tube reaches the position of the mandrel roller, the mandrel roller must be quickly opened to prevent the mandrel tube from colliding with the mandrel roller, thus avoiding accidents such as steel piling. Therefore, the opening hydraulic cylinder and the closing hydraulic cylinder need to have a sufficiently fast opening and closing speed. In the actual rolling process, the transient force generated when the mandrel roller opens and closes will directly act on the base of the worm screw lift through the piston rod of the opening hydraulic cylinder. During long-term operation, this will cause fatigue fracture of the base of the worm screw lift and it can no longer work, which will have a greater impact on the continuous production of the pipe mill. At the same time, there is an adjustment gap in the screw structure of the worm screw lift itself, and the worm screw lift is prone to position adjustment errors, which will lead to deviation in the front-end positioning of the piston rod of the opening hydraulic cylinder. For example, when the extension position of the piston rod of the opening hydraulic cylinder is too small, the mandrel roller is likely to damage the surface of the mandrel when closing, causing damage to the mandrel; when the extension position of the piston rod of the opening hydraulic cylinder is too large, there is a large gap between the mandrel roller and the mandrel when closing, which cannot effectively ensure the stability of the mandrel during the rolling process, directly affecting the wall thickness accuracy of the steel pipe at the outlet of the rolling mill, and thus affecting the quality of the finished pipe. Summary of the Invention

[0005] To solve some or all of the above-mentioned technical problems existing in the prior art, the present invention provides a hydraulic control system and control method for a mandrel support adjusting device.

[0006] The technical solution of the present invention is as follows:

[0007] According to a first aspect of the present invention, there is provided a hydraulic control system for a mandrel support adjusting device, the system comprising: a pressure reducing valve, a first pilot-operated check valve, a second pilot-operated check valve, a third pilot-operated check valve, a two-position four-way solenoid directional control valve, a three-position four-way high-frequency response proportional directional control valve, an adjusting hydraulic cylinder, and an opening hydraulic cylinder, wherein,

[0008] The inlet port of the pressure reducing valve is connected to the hydraulic oil inlet, the outlet port of the pressure reducing valve is connected to the P port of the two-position four-way solenoid directional control valve, and the outlet port of the pressure reducing valve is also connected to the outlet port of the first pilot-operated check valve;

[0009] The A port of the two-position four-way solenoid directional control valve is connected to the closed end, the B port of the two-position four-way solenoid directional control valve is connected to the control ports of the first pilot-operated check valve, the second pilot-operated check valve, and the third pilot-operated check valve, the T port of the two-position four-way solenoid directional control valve is connected to the return pipeline, and when the electromagnet Y1 of the two-position four-way solenoid directional control valve is energized, the A port is communicated with the T port, and the B port is communicated with the P port;

[0010] The P port of the three-position four-way high-frequency proportional directional valve is connected to the oil inlet of the first hydraulic check valve, the A port of the three-position four-way high-frequency proportional directional valve is connected to the oil inlet of the second hydraulic check valve, the B port of the three-position four-way high-frequency proportional directional valve is connected to the oil inlet of the third hydraulic check valve, and the T port of the three-position four-way high-frequency proportional directional valve is connected to the oil return line. When the three-position four-way high-frequency proportional directional valve is in the neutral position, the T port, A port, and B port are connected, and the P port is not connected to the above three ports.

[0011] The adjustment hydraulic cylinder includes a rod chamber and a rodless chamber. The piston rod of the adjustment hydraulic cylinder is inserted into the rod chamber, and the piston rod of the adjustment hydraulic cylinder can abut against the piston rod of the opening hydraulic cylinder. The oil outlet of the second hydraulic check valve is connected to the rod chamber of the adjustment hydraulic cylinder, and the oil outlet of the third hydraulic check valve is connected to the rodless chamber of the adjustment hydraulic cylinder.

[0012] The opening hydraulic cylinder is configured to be fixedly arranged on the rolling mill frame. One end of the piston rod of the opening hydraulic cylinder can abut against the right bearing column on the rolling mill frame, and the other end can abut against the end of the piston rod of the adjustment hydraulic cylinder.

[0013] Optionally, the system further includes: a displacement sensor and a controller.

[0014] Wherein, the displacement sensor is arranged on the adjustment hydraulic cylinder. The displacement sensor is configured to sense the position of the piston rod of the adjustment hydraulic cylinder. The displacement sensor, the three-position four-way high-frequency proportional directional valve, and the two-position four-way solenoid directional valve are all electrically connected to the controller. The controller is configured to adjust the three-position four-way high-frequency proportional directional valve according to the position of the piston rod sensed by the displacement sensor.

[0015] Optionally, when the three-position four-way high-frequency proportional directional valve is in the left position, the A port and the T port are connected, and the B port and the P port are connected; when the three-position four-way high-frequency proportional directional valve is in the right position, the A port and the P port are connected, and the B port and the T port are connected.

[0016] Optionally, the controller is a PLC control device.

[0017] Optionally, the system further includes: a cartridge pilot-operated priority unloading valve and a cartridge check valve.

[0018] Wherein, the P port of the cartridge pilot-operated priority unloading valve is connected to the rodless chamber of the adjustment hydraulic cylinder, the X port of the cartridge pilot-operated priority unloading valve is connected to the rod chamber of the adjustment hydraulic cylinder, and the T port and the Y port of the cartridge pilot-operated priority unloading valve are both connected to the oil return line; the oil inlet of the cartridge check valve is connected to the oil return line, and the oil outlet of the cartridge check valve is connected to the rod chamber of the adjustment hydraulic cylinder.

[0019] Optionally, the system further includes: a tube check valve, wherein the tube check valve is connected in series to the oil return line, and the oil outlet of the tube check valve is connected to the hydraulic oil outlet.

[0020] According to a second aspect of the present invention, there is also provided a control method for controlling the hydraulic control system of the mandrel support frame adjustment device as described in the first aspect of the present invention. The control method includes:

[0021] Move the piston rod of the adjustment hydraulic cylinder to the required position according to the rolling process requirements;

[0022] Energize the electromagnet Y1 of the two-position four-way solenoid directional valve, so that hydraulic oil enters the control ports of the first pilot-operated check valve, the second pilot-operated check valve, and the third pilot-operated check valve;

[0023] Energize the electromagnet Y2 of the three-position four-way high-response proportional directional valve, so that hydraulic oil enters the rod chamber and the non-rod chamber of the adjustment hydraulic cylinder via the pressure reducing valve and the three-position four-way high-response proportional directional valve.

[0024] The main advantages of the technical solution of the present invention are as follows:

[0025] In the hydraulic control system of the mandrel support frame adjustment device in the present invention, by filling the non-rod chamber of the adjustment hydraulic cylinder with hydraulic oil, when the opening hydraulic cylinder acts on the piston rod of the adjustment hydraulic cylinder, the hydraulic oil in the non-rod chamber can be used as a hydraulic spring to absorb the impact, and can buffer the transient force generated when the mandrel roller opens and closes. Compared with the prior art, it effectively solves the problem of the cracking of the lift base caused by using the worm gear screw jack for adjustment and positioning. Moreover, the hydraulic control system of the mandrel support frame adjustment device has a low failure rate, a compact structure, and a low equipment maintenance cost, can improve the service life of the entire device, and improve production efficiency. Description of the Drawings

[0026] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention, and do not constitute an improper limitation of the present invention. In the drawings:

[0027] Figure 1 It is a schematic installation structure diagram of the hydraulic control system of the mandrel support frame adjustment device in a continuous rolling mill according to an embodiment of the present invention;

[0028] Figure 2 It is a schematic structural principle diagram of the hydraulic control system of the mandrel support frame adjustment device according to an embodiment of the present invention.

[0029] Description of the reference numerals:

[0030] 11: Pressure reducing valve 21: First pilot-operated check valve 22: Second pilot-operated check valve

[0031] 23: Third pilot-operated check valve 13: Two-position four-way solenoid directional control valve

[0032] 14: Three-position four-way high-response proportional directional control valve 15: Cartridge check valve

[0033] 16: Cartridge pilot-operated priority unloading valve 17: Adjusting hydraulic cylinder

[0034] 18: Opening hydraulic cylinder 19: Displacement sensor 30: Controller

[0035] 31: Pipe check valve 32: Oil manifold block 200: Rolling mill housing

[0036] 210: Mandrel support frame 220: Mandrel roller 230: Mandrel

[0037] 240: Closing hydraulic cylinder 251: Right actuating column 252: Left actuating column Detailed implementation manners

[0038] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0039] The technical solutions provided by the embodiments of the present invention will be described in detail below in conjunction with the drawings.

[0040] In an embodiment according to the present invention, a hydraulic control system for a mandrel support frame adjusting device is provided. The system is used to be arranged on a continuous rolling mill, and it can replace the existing worm gear screw lift, accurately control the stroke of the adjusting hydraulic cylinder, buffer the transient force generated when the mandrel roller opens and closes during the actual steel rolling process, improve the service life of the entire device, and ensure the rolling quality at the same time. The following will be combined with Figure 1 and Figure 2 to further describe the hydraulic control system for the mandrel support frame adjusting device in this embodiment.

[0041] Specifically, as Figure 1 and Figure 2As shown in the figure, the hydraulic control system of the mandrel support adjusting device in this embodiment includes: a pressure reducing valve 11, a first pilot-operated check valve 21, a second pilot-operated check valve 22, a third pilot-operated check valve 23, a two-position four-way solenoid directional control valve 13, a three-position four-way high-response proportional directional control valve 14, an adjusting hydraulic cylinder 17, and an opening hydraulic cylinder 18.

[0042] Among them, the oil inlet of the pressure reducing valve 11 is connected to the hydraulic oil inlet, the oil outlet of the pressure reducing valve 11 is connected to the P port of the two-position four-way solenoid directional control valve 13, and the oil outlet of the pressure reducing valve 11 is also connected to the oil outlet of the first pilot-operated check valve 21.

[0043] It can be understood that the pressure reducing valve 11 is arranged on the inlet pipeline. The hydraulic oil enters the pressure reducing valve 11 through the pipeline from the hydraulic oil inlet to achieve pressure reduction. After that, the hydraulic oil passing through the pressure reducing valve 11 is divided into two paths. One path flows to the P port of the two-position four-way solenoid directional control valve 13, and the other path flows to the oil outlet of the first pilot-operated check valve 21.

[0044] The A port of the two-position four-way solenoid directional control valve 13 is connected to the closed end, the B port of the two-position four-way solenoid directional control valve 13 is connected to the control ports of the first pilot-operated check valve 21, the second pilot-operated check valve 22, and the third pilot-operated check valve 23, and the T port of the two-position four-way solenoid directional control valve 13 is connected to the return oil pipeline. Moreover, when the electromagnet Y1 of the two-position four-way solenoid directional control valve 13 is energized, the A port is communicated with the T port, and the B port is communicated with the P port.

[0045] It can be understood that the two-position four-way solenoid directional control valve 13 has a total of four ports, namely A, B, P, and T. Among them, the A port is connected to the closed end, the B port is simultaneously connected to the control ports of the first pilot-operated check valve 21, the second pilot-operated check valve 22, and the third pilot-operated check valve 23, and the T port is connected to the return oil pipeline.

[0046] Moreover, the electromagnet Y1 can control the position of the spool of the two-position four-way solenoid directional control valve 13 by being energized or de-energized. In this embodiment, when the electromagnet Y1 is energized, the A port is communicated with the T port, and the B port is communicated with the P port. When the electromagnet Y1 is de-energized, the A port is communicated with the P port, and the B port is communicated with the T port.

[0047] The P port of the three-position four-way high-response proportional directional control valve 14 is connected to the oil inlet of the first pilot-operated check valve 21, the A port of the three-position four-way high-response proportional directional control valve 14 is connected to the oil inlet of the second pilot-operated check valve 22, the B port of the three-position four-way high-response proportional directional control valve 14 is connected to the oil inlet of the third pilot-operated check valve 23, and the T port of the three-position four-way high-response proportional directional control valve 14 is connected to the return oil pipeline. Moreover, when the three-position four-way high-response proportional directional control valve 14 is in the middle position, the T port, the A port, and the B port are communicated, and the P port is not communicated with the above three ports.

[0048] It can be understood that the three-position four-way high-frequency proportional directional valve 14 also has four ports, namely A, B, P, and T. Among them, the P port is connected to the oil inlet of the first hydraulic check valve 21, the A port is connected to the oil inlet of the second hydraulic check valve 22, the B port is connected to the oil inlet of the third hydraulic check valve 23, and the T port is connected to the return pipeline.

[0049] Moreover, when the three-position four-way high-frequency proportional directional valve 14 is in the neutral position, the T port, A port, and B port are connected, and the P port is not connected to the above three ports. In this embodiment, the electromagnet Y2 can control the position of the spool of the three-position four-way high-frequency proportional directional valve 14 through the received electrical signal.

[0050] The adjusting hydraulic cylinder 17 includes a rod chamber and a rodless chamber. The piston rod of the adjusting hydraulic cylinder 17 is inserted into the rod chamber. The piston rod of the adjusting hydraulic cylinder 17 can extend out of the rod chamber and abut against the piston rod of the opening hydraulic cylinder 18. The oil outlet of the second hydraulic check valve 22 is connected to the rod chamber of the adjusting hydraulic cylinder 17, and the oil outlet of the third hydraulic check valve 23 is connected to the rodless chamber of the adjusting hydraulic cylinder 17.

[0051] It can be understood that based on the movement of the piston rod of the adjusting hydraulic cylinder 17, the cylinder barrel of the adjusting hydraulic cylinder 17 can be divided into two chambers. Among them, the chamber containing the piston rod is the rod chamber, and the other is the rodless chamber. The rod chamber is connected to the oil outlet of the second hydraulic check valve 22 through a pipeline and can receive hydraulic oil from the second hydraulic check valve 22. The rodless chamber is connected to the oil outlet of the third hydraulic check valve 23 through a pipeline and can receive hydraulic oil from the third hydraulic check valve 23.

[0052] In addition, the piston rod of the adjusting hydraulic cylinder 17 can abut against the piston rod of the opening hydraulic cylinder 18 to facilitate positioning of the piston rod of the opening hydraulic cylinder 18.

[0053] The opening hydraulic cylinder 18 is configured to be fixedly arranged on the rolling mill frame 200. One end of the piston rod of the opening hydraulic cylinder 18 can abut against the right supporting column 251 on the rolling mill frame 200, and the other end can abut against the end of the piston rod of the adjusting hydraulic cylinder 17.

[0054] It can be understood that the cylinder barrel of the opening hydraulic cylinder 18 can be fixed on the rolling mill frame 200. The piston rod of the opening hydraulic cylinder 18 can be driven and abut against the right supporting column 251 on the rolling mill frame 200. Moreover, when it retracts, it can abut against the end of the piston rod of the adjusting hydraulic cylinder 17.

[0055] In this embodiment, the piston rod of the opening hydraulic cylinder 18 can be controlled by an external separate hydraulic control valve.

[0056] As Figure 1As shown, before the rolling process starts, according to the mandrel diameter determined by the continuous rolling mill rolling process, the piston rod of the adjustment hydraulic cylinder 17 is adjusted to the required position. Then, the electromagnet Y1 is energized. At this time, the first hydraulic control check valve 21, the second hydraulic control check valve 22, and the third hydraulic control check valve 23 are opened simultaneously. An electrical signal is input to the electromagnet Y2, and the hydraulic oil enters the rod chamber and the rodless chamber of the adjustment hydraulic cylinder 17 through the pressure reducing valve 11, the first hydraulic control check valve 21, the three-position four-way high-response proportional reversing valve 14, and the second hydraulic control check valve 22 and the third hydraulic control check valve 23 respectively.

[0057] During this process, the pressure reducing valve 11 can not only ensure the stable pressure of the hydraulic oil entering the three-position four-way high-response proportional reversing valve 14, improve the positioning accuracy of the adjustment hydraulic cylinder 17, but also effectively reduce the adjustment force of the adjustment hydraulic cylinder 17, preventing the fixing device of the adjustment hydraulic cylinder 17 from being damaged due to excessive adjustment force.

[0058] In this embodiment, in order to ensure reliable cut-off of the hydraulic oil and avoid the position deviation of the oil cylinder caused by the hydraulic oil entering the high-response proportional valve, the first hydraulic control check valve 21 is installed reversely. Thus, only when the electromagnet Y1 of the two-position four-way electromagnetic reversing valve 13 is energized, the hydraulic oil will enter the control ports of the first hydraulic control check valve 21, the second hydraulic control check valve 22, and the third hydraulic control check valve 23. At this time, the first hydraulic control check valve 21, the second hydraulic control check valve 22, and the third hydraulic control check valve 23 will be opened simultaneously.

[0059] Preferably, the main spool of the three-position four-way high-response proportional reversing valve 14 has position feedback, and can adjust the adjustment hydraulic cylinder 17 in place in real time and quickly.

[0060] In an alternative embodiment, after the proportional electromagnet of the three-position four-way high-response proportional reversing valve 14 is energized, it can drive the main valve spool to act. The main valve spool is equipped with a position sensor. Through this position sensor, the opening direction and opening amount of the main valve spool moving in the valve body can achieve continuous and controllable internal feedback. By precisely controlling the displacement of the main valve spool changing with the follower, the flow rate of the hydraulic oil entering the adjustment hydraulic cylinder 17 can be adjusted.

[0061] During the actual steel rolling process, as Figure 1 shown, the piston rod of the opening hydraulic cylinder 18 is driven to move towards the right supporting column 251 and push the right supporting column 251 to move leftward. At the same time, the piston rod of the closing hydraulic cylinder 240 located on the left retracts, so that the three mandrel rollers 220 are opened, allowing the mandrel 230 to penetrate between the three mandrel rollers 220 along the center line of the continuous rolling mill.

[0062] After the mandrel 230 reaches the predetermined position, the piston rod of the closing hydraulic cylinder 240 on the left side extends rapidly, pushing the left actuating column 252 to move rightward. At the same time, the piston rod of the opening hydraulic cylinder 18 retracts until the rear end of the piston rod of the opening hydraulic cylinder 18 abuts against the end of the piston rod of the adjusting hydraulic cylinder 17. The three mandrel rollers 220 hold the mandrel 230 tightly. When the piston rod of the adjusting hydraulic cylinder 17 is impacted by the piston rod of the opening hydraulic cylinder 18, the rodless cavity of the adjusting hydraulic cylinder 17 is filled with hydraulic oil, and the hydraulic oil can act as a hydraulic spring to absorb the impact. Thus, the transient force generated when the mandrel rollers 220 open and close is buffered, improving the service life of the entire device.

[0063] Furthermore, in order to effectively control the position of the piston rod of the adjusting hydraulic cylinder 17, as Figure 2 shown, the hydraulic control system of the mandrel support adjusting device further includes: a displacement sensor 19 and a controller 30.

[0064] Specifically, the displacement sensor 19 is arranged on the adjusting hydraulic cylinder 17. The displacement sensor 19 is configured to sense the position of the piston rod of the adjusting hydraulic cylinder 17. The displacement sensor 19, the three-way four-position high-response proportional directional control valve 14, and the two-way four-position solenoid directional control valve 13 are all electrically connected to the controller 30. The controller 30 is configured to adjust the three-way four-position high-response proportional directional control valve 14 according to the position of the piston rod sensed by the displacement sensor 19.

[0065] In practical applications, when the displacement sensor 19 detects that the position change of the piston rod of the adjusting hydraulic cylinder 17 exceeds the set range value, it transmits the corresponding adjustment position signal to the controller 30. The controller 30 controls the electromagnet Y1 of the two-way four-position solenoid directional control valve 13 to be energized, and the first hydraulic control check valve 21, the second hydraulic control check valve 22, and the third hydraulic control check valve 23 are opened simultaneously. At the same time, the controller 30 inputs an adjustment signal to the electromagnet Y2 of the three-way four-position high-response proportional directional control valve 14, causing the spool position of the three-way four-position high-response proportional directional control valve 14 to change, so as to quickly compensate the hydraulic oil in the rod cavity and the rodless cavity to the set value, making the piston rod of the adjusting hydraulic cylinder 17 reach the required position, and further ensuring that the adjustment position of the mandrel roller is accurately controllable.

[0066] It can be understood that before rolling steel, the closing hydraulic cylinder 240 will push the left actuating column 252 to move rightward, the mandrel rollers 220 hold the mandrel tightly, and the right actuating column 251 is simultaneously pushed to abut against the left end of the piston rod of the opening hydraulic cylinder 18, and the right end of the piston rod of the opening hydraulic cylinder 18 will abut against the piston rod of the adjusting hydraulic cylinder 17.

[0067] During the rolling process, before the mandrel roller 220 reaches its position, the mandrel roller 220 must be quickly opened. The left end of the piston rod of the opening hydraulic cylinder 18 pushes the right support column 251 to move leftward. At the same time, the right end of the piston rod of the opening hydraulic cylinder 18 disengages from the piston rod of the adjusting hydraulic cylinder 17. The three mandrel rollers 220 are opened, and at the same time, the piston rod of the closing hydraulic cylinder 240 contracts and retracts.

[0068] Specifically, in this embodiment, when the three-way four-way high-frequency response proportional direction valve 14 is in the left position, port A and port T are connected, and port B and port P are connected; when the three-way four-way high-frequency response proportional direction valve 14 is in the right position, port A and port P are connected, and port B and port T are connected.

[0069] Thus, when it is necessary to replenish oil to the rod chamber, the three-way four-way high-frequency response proportional direction valve 14 can be made to be in the right position. When it is necessary to replenish oil to the non-rod chamber, the three-way four-way high-frequency response proportional direction valve 14 can be made to be in the left position.

[0070] Exemplarily, the controller 30 can be a PLC control device.

[0071] Further, in this embodiment, as Figure 2 shown, the hydraulic control system of the mandrel support adjusting device further includes: a cartridge pilot-operated priority unloading valve 16 and a cartridge check valve 15.

[0072] Specifically, the P port of the cartridge pilot-operated priority unloading valve 16 is connected to the non-rod chamber of the adjusting hydraulic cylinder 17. The X port of the cartridge pilot-operated priority unloading valve 16 is connected to the rod chamber of the adjusting hydraulic cylinder 17. The T port and the Y port of the cartridge pilot-operated priority unloading valve 16 are both connected to the oil return pipeline. The inlet port of the cartridge check valve 15 is connected to the oil return pipeline, and the outlet port of the cartridge check valve 15 is connected to the rod chamber of the adjusting hydraulic cylinder 17.

[0073] Thus, in actual use, when the adjusting hydraulic cylinder 17 is in the high-frequency adjustment process, once the oil pressure in the rod chamber or the non-rod chamber is too high, the cartridge pilot-operated priority unloading valve 16 can pre-unload the pressure mutations in both the rod chamber and the non-rod chamber of the adjusting hydraulic cylinder 17 simultaneously, avoiding a large pressure impact on the opening hydraulic cylinder 18 or the rolling mill frame 200 by the adjusting hydraulic cylinder 17.

[0074] Moreover, in this embodiment, both the cartridge check valve 15 and the cartridge pilot-operated priority unloading valve 16 can be integrally inserted into the oil circuit block 32, thus ensuring that hydraulic oil does not leak, and the entire structure is more compact.

[0075] Optionally, in this embodiment, as Figure 2As shown, the hydraulic control system of the mandrel support frame adjustment device further includes: a tube-type one-way valve 31. Among them, the tube-type one-way valve 31 is connected in series to the oil return pipeline, and the oil outlet of the tube-type one-way valve 31 is connected to the hydraulic oil outlet.

[0076] In actual use, when the oil pressure impact pressure in the rodless cavity exceeds the protection pressure set by the cartridge pilot-operated priority unloading valve 16, the pressure can be relieved to the oil return pipeline through the cartridge pilot-operated priority unloading valve 16. At the same time, the rod cavity of the hydraulic cylinder 17 is quickly replenished with oil through the cartridge one-way valve 15. At this time, the tube-type one-way valve 31 can ensure that the oil return pipeline is always filled with low-pressure hydraulic oil.

[0077] Thus, in this embodiment, by arranging the tube-type one-way valve 31 in the oil return pipeline, on the one hand, when the oil pressure impact pressure in the rodless cavity exceeds the protection pressure set by the cartridge pilot-operated priority unloading valve 16, the rod cavity can be quickly replenished with oil. On the other hand, it can also maintain the oil return back pressure at the T port of the three-position four-way high-frequency response proportional directional valve 14, thereby improving the response ability of this directional valve.

[0078] In this embodiment, a control method is also provided. This control method is used to control the hydraulic control system of the mandrel support frame adjustment device in this embodiment. This control method includes:

[0079] According to the rolling process requirements, move the piston rod of the adjustment hydraulic cylinder to the required position;

[0080] Energize the electromagnet Y1 of the two-position four-way electromagnetic directional valve, so that the hydraulic oil enters the control ports of the first hydraulic control one-way valve, the second hydraulic control one-way valve, and the third hydraulic control one-way valve;

[0081] Energize the electromagnet Y2 of the three-position four-way high-frequency response proportional directional valve, so that the hydraulic oil enters the rod cavity and the rodless cavity of the adjustment hydraulic cylinder via the pressure reducing valve and the three-position four-way high-frequency response proportional directional valve.

[0082] Thus, the system in this embodiment has the following advantages:

[0083] First, by filling the rodless cavity of the adjustment hydraulic cylinder with hydraulic oil, when the opening hydraulic cylinder acts on the piston rod of the adjustment hydraulic cylinder, the hydraulic oil in this rodless cavity can be used as a hydraulic spring to absorb the impact, and can buffer the transient force generated when the mandrel roller opens and closes. Compared with the prior art, it effectively solves the problem of cracking of the lift base caused by using the worm and screw lift for adjustment and positioning. Moreover, the hydraulic control system of this mandrel support frame adjustment device has a low failure rate, a compact structure, and a low equipment maintenance cost, and can improve the service life of the entire device and improve production efficiency;

[0084] Second, by enabling the displacement sensor to sense the position of the piston rod of the adjusting hydraulic cylinder, the controller can input an electrical signal to the three-position four-way high-frequency response proportional directional valve based on the position information sensed by the displacement sensor, and can timely adjust the position of the piston rod of the adjusting hydraulic cylinder, thereby positioning the opening size of the mandrel roller in real time, quickly, and accurately. This avoids the adjustment error caused by the gap between the lead screws in the prior art when using a worm screw lift, effectively solves the problem of mandrel surface bruising, ensures the stability of the mandrel during the rolling process, and can improve the wall thickness accuracy of the finished pipe.

[0085] Third, by setting up a cartridge pilot-operated priority unloading valve, it is possible to pre-unload the pressure mutations in both the rod chamber and the non-rod chamber of the adjusting hydraulic cylinder simultaneously, avoiding the rigid impact of the adjusting hydraulic cylinder on the rolling mill frame.

[0086] Fourth, by setting up a cartridge check valve, oil can be quickly replenished after the transient position of the rod chamber changes. Moreover, when the adjusting hydraulic cylinder is in the locked rolling state, this cartridge structure can prevent hydraulic oil leakage.

[0087] It should be noted that in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. In addition, in this article, "front", "rear", "left", "right", "upper", and "lower" are all referenced based on the placement state shown in the drawings.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A hydraulic control system for a mandrel support frame adjustment device, characterized in that, The system includes: a pressure reducing valve, a first pilot-operated check valve, a second pilot-operated check valve, a third pilot-operated check valve, a two-position four-way solenoid-operated directional control valve, a three-position four-way high-response proportional directional control valve, an adjusting hydraulic cylinder, and an opening hydraulic cylinder. Among them, The inlet port of the pressure reducing valve is connected to the hydraulic oil inlet, the outlet port of the pressure reducing valve is connected to the P port of the two-position four-way solenoid-operated directional control valve, and the outlet port of the pressure reducing valve is also connected to the outlet port of the first pilot-operated check valve; The A port of the two-position four-way solenoid-operated directional control valve is connected to the closed end, the B port of the two-position four-way solenoid-operated directional control valve is connected to the control ports of the first pilot-operated check valve, the second pilot-operated check valve, and the third pilot-operated check valve, and the T port of the two-position four-way solenoid-operated directional control valve is connected to the return pipeline. Moreover, when the electromagnet Y1 of the two-position four-way solenoid-operated directional control valve is energized, the A port is communicated with the T port, and the B port is communicated with the P port; The P port of the three-position four-way high-response proportional directional control valve is connected to the inlet port of the first pilot-operated check valve, the A port of the three-position four-way high-response proportional directional control valve is connected to the inlet port of the second pilot-operated check valve, the B port of the three-position four-way high-response proportional directional control valve is connected to the inlet port of the third pilot-operated check valve, and the T port of the three-position four-way high-response proportional directional control valve is connected to the return pipeline. Moreover, when the three-position four-way high-response proportional directional control valve is in the middle position, the T port, the A port, and the B port are communicated, and the P port is not communicated with the above three ports; The adjusting hydraulic cylinder includes a rod chamber and a rodless chamber. The piston rod of the adjusting hydraulic cylinder is inserted into the rod chamber. The piston rod of the adjusting hydraulic cylinder can extend out of the rod chamber and abut against the piston rod of the opening hydraulic cylinder. The outlet port of the second pilot-operated check valve is connected to the rod chamber of the adjusting hydraulic cylinder, and the outlet port of the third pilot-operated check valve is connected to the rodless chamber of the adjusting hydraulic cylinder; The opening hydraulic cylinder is configured to be fixedly arranged on the rolling mill frame. One end of the piston rod of the opening hydraulic cylinder can abut against the right bearing column on the rolling mill frame, and the other end can abut against the end of the piston rod of the adjusting hydraulic cylinder.

2. The hydraulic control system of the mandrel support frame adjusting device according to claim 1, wherein, The system further includes: a displacement sensor and a controller, Among them, the displacement sensor is arranged on the adjusting hydraulic cylinder. The displacement sensor is configured to sense the position of the piston rod of the adjusting hydraulic cylinder. The displacement sensor, the three-position four-way high-response proportional directional control valve, and the two-position four-way solenoid-operated directional control valve are all electrically connected to the controller. The controller is configured to adjust the three-position four-way high-response proportional directional control valve according to the position of the piston rod sensed by the displacement sensor.

3. The hydraulic control system of the mandrel support frame adjusting device according to claim 2, characterized in that, When the three-position four-way high-response proportional directional control valve is in the left position, the A port and the T port are communicated, and the B port and the P port are communicated; when the three-position four-way high-response proportional directional control valve is in the right position, the A port and the P port are communicated, and the B port and the T port are communicated.

4. The hydraulic control system of the mandrel support frame adjusting device according to claim 2, wherein, The controller is a PLC control device.

5. The hydraulic control system of the mandrel support frame adjusting device according to claim 1, characterized in that The system further includes: a cartridge-type pilot-operated priority unloading valve and a cartridge-type check valve, Among them, the P port of the cartridge pilot-operated priority unloading valve is connected to the rodless cavity of the adjustment hydraulic cylinder, the X port of the cartridge pilot-operated priority unloading valve is connected to the rod cavity of the adjustment hydraulic cylinder, and the T port and Y port of the cartridge pilot-operated priority unloading valve are both connected to the oil return pipeline; the oil inlet of the cartridge check valve is connected to the oil return pipeline, and the oil outlet of the cartridge check valve is connected to the rod cavity of the adjustment hydraulic cylinder.

6. The hydraulic control system of the mandrel support frame adjusting device according to claim 1, characterized in that The system further includes: a pipe check valve, wherein the pipe check valve is connected in series to the oil return pipeline, and the oil outlet of the pipe check valve is connected to the hydraulic oil outlet.

7. A control method, characterized in that, The control method is used to control the hydraulic control system of the mandrel support adjustment device as described in claim 1, and the control method includes: According to the rolling process requirements, move the piston rod of the adjustment hydraulic cylinder to the required position; Energize the electromagnet Y1 of the two-position four-way solenoid directional valve, so that hydraulic oil enters the control ports of the first hydraulic control check valve, the second hydraulic control check valve, and the third hydraulic control check valve; Energize the electromagnet Y2 of the three-position four-way high-frequency response proportional directional valve, so that hydraulic oil enters the rod cavity and the rodless cavity of the adjustment hydraulic cylinder via the pressure reducing valve and the three-position four-way high-frequency response proportional directional valve.

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