CN107052283B - Crystallizer vibration control device - Google Patents
Crystallizer vibration control device Download PDFInfo
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- CN107052283B CN107052283B CN201710076072.8A CN201710076072A CN107052283B CN 107052283 B CN107052283 B CN 107052283B CN 201710076072 A CN201710076072 A CN 201710076072A CN 107052283 B CN107052283 B CN 107052283B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
- B22D11/053—Means for oscillating the moulds
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/16—Controlling or regulating processes or operations
- B22D11/166—Controlling or regulating processes or operations for mould oscillation
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- Mechanical Engineering (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention relates to a crystallizer vibration control device which comprises a driving mechanism, a bidirectional quantitative pump, an electromagnetic cut-off valve, a first energy accumulator and a single-outlet-rod three-cavity hydraulic cylinder, wherein the output end of the driving mechanism is connected with the input end of the bidirectional quantitative pump, the A port of the bidirectional quantitative pump is connected with the A cavity of the single-outlet-rod three-cavity hydraulic cylinder, the B port of the bidirectional quantitative pump is connected with the B cavity of the single-outlet-rod three-cavity hydraulic cylinder, the electromagnetic cut-off valve is arranged on a pipeline between the B port of the bidirectional quantitative pump and the B cavity of the single-outlet-rod three-cavity hydraulic cylinder, the first energy accumulator is connected with the C cavity of the single-outlet-rod three-cavity hydraulic cylinder, and the output shaft of the single-outlet-rod three-cavity hydraulic cylinder is connected with a vibration load. The invention has the advantages that: the problem of mismatching of the area ratio control flow of the two cavities of the single-output-rod asymmetric hydraulic cylinder is completely solved, meanwhile, the gravity load is balanced, the installed power is reduced, the operation energy consumption is reduced, and the investment and the operation cost of a crystallizer vibration system can be greatly reduced on the premise of meeting the control precision and the response characteristic of the system.
Description
Technical Field
The invention relates to the technical field of continuous casting crystallizer vibration, in particular to a crystallizer vibration control device.
Background
The crystallizer vibration device is used as key equipment of a continuous casting machine, and has the function of ensuring that a casting blank and a copper wall of the crystallizer are not bonded in the casting process through vibration of the crystallizer, and obtaining good surface quality of the casting blank. The existing crystallizer vibration device is divided into mechanical vibration, hydraulic servo vibration and electric cylinder vibration according to a driving control mode. The mechanical crystallizer vibrating device usually adopts a rotating motor and an eccentric wheel connecting rod mechanism to realize sinusoidal vibration, and has the defects that the mechanical abrasion is serious, the non-sinusoidal vibration, the vibration parameters such as amplitude, deflection and the like are difficult to realize, and the vibration parameters cannot be adjusted on line; the hydraulic servo crystallizer vibration device adopts an electrohydraulic servo valve to control a hydraulic cylinder to realize sinusoidal and non-sinusoidal vibration, and can conveniently realize on-line adjustment and monitoring of amplitude, frequency and waveform; the electric cylinder crystallizer vibrating device adopts the servo electric cylinder to directly drive the crystallizer vibrating table to realize sinusoidal and non-sinusoidal vibration, has the advantages of lower cost, convenient equipment maintenance, no pollution and the like, but has the defects of poor shock resistance, easy abrasion, short service life and the like of a lead screw of a core transmission component, and restricts the wider application of the electric cylinder crystallizer vibrating device.
With the development of hydraulic technology, a novel servo driving mode, namely a direct-drive electrohydraulic servo system, appears. The three functions of reversing, speed regulating and pressure regulating of the direct-drive electrohydraulic servo system are directly controlled by a servo motor, and a conventional electrohydraulic servo valve is not needed, so that the requirement on the cleanliness of oil is greatly reduced. Compared with the traditional electrohydraulic servo system, the direct-drive electrohydraulic servo system has the multiple advantages of flexible servo motor transmission control, low electric transmission energy consumption and large hydraulic transmission output.
PCT international patent publication No. WO2015/121829 A1 discloses the application of a direct drive electrohydraulic servo system to a single side drive crystallizer vibration device, and discloses two control loops for a double-rod symmetric cylinder and a single-rod asymmetric cylinder actuator. The control scheme has the advantages that the area ratio of the two cavities of the asymmetric cylinder is matched, the displacement of the quantitative pump is determined, the displacement of the commercial quantitative pump is of a certain series, the displacement ratio of the large pump and the small pump is difficult to completely correspond to the area ratio of the two cavities of the asymmetric cylinder through selection, so that the pressure fluctuation and control of the two cavities are difficult, and the final control accuracy is affected; if the two-cavity area ratio of the asymmetric cylinder is completely corresponding through the customization of the displacement of the constant displacement pump, the cost is greatly increased. Meanwhile, under sinusoidal or non-sinusoidal movement of two control loops of the double-rod symmetrical cylinder and the single-rod asymmetrical cylinder, loads to be overcome comprise gravity of the crystallizer and the vibrating rack, friction force and inertia force of the crystallizer and a casting blank, wherein the gravity of the crystallizer and the vibrating rack occupies a maximum ratio of about 20 tons and occupies about 90% of the total load, so that the overall power configuration of the system is greatly increased, and the investment and the running cost are increased.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, provides a crystallizer vibration control device, and provides a single-rod three-cavity cylinder control scheme controlled by a direct-drive electrohydraulic servo system and an energy accumulator, which not only completely solves the problem of mismatching of control flow of the area ratio of two cavities of a single-rod asymmetric hydraulic cylinder, but also balances gravity load, reduces installed power, reduces operation energy consumption, and can greatly reduce investment and operation cost of a crystallizer vibration system on the premise of meeting the control precision and response characteristic of the system.
The aim of the invention is achieved by the following technical scheme: the utility model provides a crystallizer vibration control device, includes actuating mechanism, two-way constant delivery pump, electromagnetic cut-off valve, first energy storage ware and single three-chamber pneumatic cylinder of going out the pole, actuating mechanism's output is connected with the input of two-way constant delivery pump, and two-way constant delivery pump has A mouth and B mouth, single three-chamber pneumatic cylinder of going out the pole has A chamber, B chamber and C chamber, and two-way constant delivery pump's A mouth is connected with single three-chamber pneumatic cylinder of going out the pole A chamber, and two-way constant delivery pump's B mouth is connected with single three-chamber pneumatic cylinder of going out the B chamber of going out the pole, be equipped with electromagnetic cut-off valve on the pipeline between two-way constant delivery pump's B mouth and the B chamber of single three-chamber pneumatic cylinder of going out the pole, first energy storage ware is connected with single three-chamber pneumatic cylinder of going out the pole, single three-chamber pneumatic cylinder's output shaft vibration load.
The sectional areas of the A cavity and the B cavity of the single-rod three-cavity hydraulic cylinder are equal.
The device also comprises a second energy accumulator which is respectively connected with the port A of the bidirectional constant delivery pump, the port B of the bidirectional constant delivery pump and the first energy accumulator.
A first one-way valve is arranged between the second energy accumulator and an A port of the bidirectional quantitative pump, and a second one-way valve is arranged between the second energy accumulator and a B port of the bidirectional quantitative pump.
A first safety valve is further arranged between the second energy accumulator and the port A of the bidirectional quantitative pump, a second safety valve is further arranged between the second energy accumulator and the port B of the bidirectional quantitative pump, and a third safety valve is arranged between the second energy accumulator and the first energy accumulator.
And a pressure reducing valve is further arranged between the first energy accumulator and the B cavity of the single-rod three-cavity hydraulic cylinder.
The control assembly comprises a first pressure sensor, a second pressure sensor, a third pressure sensor, a displacement sensor, a controller and a driver, wherein the first pressure sensor is arranged at a cavity B of the single-output-rod three-cavity hydraulic cylinder, the second pressure sensor is arranged at a cavity A of the single-output-rod three-cavity hydraulic cylinder, the third pressure sensor is arranged at a cavity C of the single-output-rod three-cavity hydraulic cylinder, the displacement sensor is arranged at an output shaft of the single-output-rod three-cavity hydraulic cylinder, the first pressure sensor, the second pressure sensor, the third pressure sensor and the displacement sensor are respectively connected with a signal input end of the controller, a signal output end of the controller is connected with a signal input end of the driver, and a signal output end of the driver is connected with a signal input end of the driving mechanism.
The driving mechanism is a servo motor.
The signal output end of the controller is connected with the signal input end of the electromagnetic cut-off valve.
The invention has the following advantages:
1. according to the invention, the energy accumulator and the two-way pump are adopted to control the single-rod-outlet three-cavity hydraulic cylinder, the motion control of the single-rod-outlet hydraulic cylinder is realized by one pump, and meanwhile, the control of the asymmetric hydraulic cylinder is converted into the control of the symmetric hydraulic cylinder, so that the problem of unbalanced flow of the asymmetric hydraulic cylinder is solved, the control scheme is simplified, and the control difficulty is reduced.
2. The gravity load is balanced by adopting the energy accumulator and the single-rod three-cavity hydraulic cylinder, so that the vibration system only needs to overcome friction force and inertia force, the installed power is greatly reduced, and the operation energy consumption is reduced.
Drawings
FIG. 1 is a schematic diagram of the system principle of the present invention;
in the figure: the hydraulic system comprises a 1-driving mechanism, a 2-bidirectional constant delivery pump, a 3-first one-way valve, a 4-second one-way valve, a 5-first safety valve, a 6-second safety valve, a 7-second energy accumulator, an 8-electromagnetic shut-off valve, a 9-first pressure sensor, a 10-second pressure sensor, a 11-third safety valve, a 12-pressure reducing valve, a 13-first energy accumulator, a 14-third pressure sensor, a 15-single-rod three-cavity hydraulic cylinder, a 16-displacement sensor, a 17-vibration load, a 18-controller and a 19-driver.
Detailed Description
The present invention will be further described with reference to the accompanying drawings, but the scope of the present invention is not limited to the following.
As shown in fig. 1, a crystallizer vibration control device comprises a driving mechanism 1, a bidirectional quantitative pump 2, an electromagnetic cut-off valve 8, a first energy accumulator 13 and a single-outlet rod three-cavity hydraulic cylinder 15, wherein the output end of the driving mechanism 1 is connected with the input end of the bidirectional quantitative pump 2, the bidirectional quantitative pump 2 is provided with an A port and a B port, the single-outlet rod three-cavity hydraulic cylinder 15 is provided with an A cavity, a B cavity and a C cavity, the A port of the bidirectional quantitative pump 2 is connected with the A cavity of the single-outlet rod three-cavity hydraulic cylinder 15, the B port of the bidirectional quantitative pump 2 is connected with the B cavity of the single-outlet rod three-cavity hydraulic cylinder 15, the electromagnetic cut-off valve 8 is arranged on a pipeline between the B port of the bidirectional quantitative pump 2 and the B cavity of the single-outlet rod three-cavity hydraulic cylinder 15, the first energy accumulator 13 is connected with the C cavity of the single-outlet rod three-cavity hydraulic cylinder 15, and the output shaft of the single-outlet rod three-cavity hydraulic cylinder 15 is connected with a vibration load 17.
Preferably, the sectional areas of the A cavity and the B cavity of the single-rod three-cavity hydraulic cylinder 15 are equal.
Preferably, the hydraulic pump further comprises a second energy accumulator 7, wherein the second energy accumulator 7 is respectively connected with the port A of the bidirectional constant displacement pump 2, the port B of the bidirectional constant displacement pump 2 and the first energy accumulator 13, and the second energy accumulator 7 is also connected with the oil discharging port of the bidirectional constant displacement pump 2.
Preferably, a first one-way valve 3 is arranged between the second accumulator 7 and the port A of the bidirectional constant delivery pump 2 to realize the oil supplementing function of the cavity A of the single-rod three-cavity hydraulic cylinder 15, a second one-way valve 4 is arranged between the second accumulator 7 and the port B of the bidirectional constant delivery pump 2, and the second one-way valve 4 realizes the oil supplementing function of the cavity B of the single-rod three-cavity hydraulic cylinder 15.
Preferably, a first safety valve 5 is further arranged between the second accumulator 7 and the port a of the bidirectional quantitative pump 2, a second safety valve 6 is further arranged between the second accumulator 7 and the port B of the bidirectional quantitative pump 2, and a third safety valve 11 is arranged between the second accumulator 7 and the first accumulator 13 to prevent the double cavities of the bidirectional quantitative pump 2 and the first accumulator 13 from being overpressurized.
Preferably, a pressure reducing valve 12 is further disposed between the first accumulator 13 and the B cavity of the single-rod three-cavity hydraulic cylinder 15, an inlet of the pressure reducing valve 12 is connected to the B cavity of the single-rod three-cavity hydraulic cylinder 15, and an outlet of the pressure reducing valve is connected to the first accumulator 13.
Preferably, the hydraulic control device also comprises a control assembly, wherein the control assembly comprises a first pressure sensor 9, a second pressure sensor 10, a third pressure sensor 14, a displacement sensor 16, a controller 18 and a driver 19, the first pressure sensor 9 is arranged at a B cavity of the single-rod three-cavity hydraulic cylinder 15, the second pressure sensor 10 is arranged at an A cavity of the single-rod three-cavity hydraulic cylinder 15, the third pressure sensor 14 is arranged at a C cavity of the single-rod three-cavity hydraulic cylinder 15, the displacement sensor 16 is arranged at an output shaft of the single-rod three-cavity hydraulic cylinder 15, the first pressure sensor 9, the second pressure sensor 10, the third pressure sensor 14 and the displacement sensor 16 are respectively connected with a signal input end of a controller 18, a signal output end of the controller 18 is connected with a signal input end of a driver 19, a signal output end of the driver 19 is connected with a signal input end of the driving mechanism 1, signals of the first pressure sensor 9, the electromagnetic cut-off valve 8, the second pressure sensor 10, the third pressure sensor 14 and the displacement sensor 16 are connected into the controller 18, a control instruction of the controller 18 is connected into the driver 19, and a driving instruction of the driver 19 is connected into the driving mechanism 1.
Preferably, the driving mechanism 1 is a servo motor.
Preferably, the signal output end of the controller 18 is connected with the signal input end of the electromagnetic cut-off valve 8, so that the oil circuit is conducted when electricity is obtained in a normal state, and the current position of the single-rod three-cavity hydraulic cylinder 15 is locked in a power-losing state, so that the function of stopping the single-rod three-cavity hydraulic cylinder 15 can be realized.
The working principle of the invention is as follows: when the crystallizer vibration system works, the controller 18 receives a vibration curve set by an external PLC instruction, converts and outputs the vibration curve to the driver 19 through a control algorithm, the driver 19 drives the driving mechanism 1 to forward and reverse according to the given instruction, the forward and reverse rotation of the driving mechanism 1 drives the bidirectional constant delivery pump 2 to forward and reverse rotation, and the forward and reverse rotation of the bidirectional constant delivery pump 2 drives the single-rod three-cavity hydraulic cylinder 15 to extend and retract.
Claims (3)
1. A crystallizer vibration control device is characterized in that: the hydraulic system comprises a driving mechanism (1), a bidirectional quantitative pump (2), an electromagnetic cut-off valve (8), a first energy accumulator (13) and a single-output-rod three-cavity hydraulic cylinder (15), wherein the output end of the driving mechanism (1) is connected with the input end of the bidirectional quantitative pump (2), the bidirectional quantitative pump (2) is provided with an A port and a B port, the single-output-rod three-cavity hydraulic cylinder (15) is provided with an A cavity, a B cavity and a C cavity, the A port of the bidirectional quantitative pump (2) is connected with the A cavity of the single-output-rod three-cavity hydraulic cylinder (15), the B port of the bidirectional quantitative pump (2) is connected with the B cavity of the single-output-rod three-cavity hydraulic cylinder (15), the electromagnetic cut-off valve (8) is arranged on a pipeline between the B port of the bidirectional quantitative pump (2) and the B cavity of the single-output-rod three-cavity hydraulic cylinder (15), and the first energy accumulator (13) is connected with the C cavity of the single-output-rod three-cavity hydraulic cylinder (15), and the output shaft of the single-rod three-cavity hydraulic cylinder (15) is connected with a vibration load (17); the sectional areas of the cavity A and the cavity B of the single-rod three-cavity hydraulic cylinder (15) are equal;
the device also comprises a second energy accumulator (7), wherein the second energy accumulator (7) is respectively connected with an A port of the bidirectional constant delivery pump (2), a B port of the bidirectional constant delivery pump (2) and the first energy accumulator (13);
a first one-way valve (3) is arranged between the second energy accumulator (7) and an A port of the bidirectional quantitative pump (2), and a second one-way valve (4) is arranged between the second energy accumulator (7) and a B port of the bidirectional quantitative pump (2); a first safety valve (5) is further arranged between the second energy accumulator (7) and the port A of the bidirectional quantitative pump (2), a second safety valve (6) is further arranged between the second energy accumulator (7) and the port B of the bidirectional quantitative pump (2), and a third safety valve (11) is arranged between the second energy accumulator (7) and the first energy accumulator (13);
a pressure reducing valve (12) is arranged between the first energy accumulator (13) and the B cavity of the single-rod three-cavity hydraulic cylinder (15);
still include control assembly, control assembly includes first pressure sensor (9), second pressure sensor (10), third pressure sensor (14), displacement sensor (16), controller (18) and driver (19), first pressure sensor (9) set up in the B chamber department of single three chamber pneumatic cylinders of pole (15), second pressure sensor (10) set up in the A chamber department of single three chamber pneumatic cylinders of pole (15), third pressure sensor (14) set up in the C chamber department of single three chamber pneumatic cylinders of pole (15), displacement sensor (16) set up in the output shaft department of single three chamber pneumatic cylinders of pole (15), first pressure sensor (9), second pressure sensor (10), third pressure sensor (14) and displacement sensor (16) are connected with the signal input part of controller (18) respectively, the signal output part of controller (18) is connected with the signal input part of driver (19), the signal output part of driver (19) is connected with the signal input part of actuating mechanism (1).
2. The crystallizer vibration control device according to claim 1, wherein: the driving mechanism (1) is a servo motor.
3. The crystallizer vibration control device according to claim 2, wherein: the signal output end of the controller (18) is connected with the signal input end of the electromagnetic cut-off valve (8).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710076072.8A CN107052283B (en) | 2017-02-10 | 2017-02-10 | Crystallizer vibration control device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710076072.8A CN107052283B (en) | 2017-02-10 | 2017-02-10 | Crystallizer vibration control device |
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| CN107052283A CN107052283A (en) | 2017-08-18 |
| CN107052283B true CN107052283B (en) | 2023-08-15 |
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| CN201710076072.8A Active CN107052283B (en) | 2017-02-10 | 2017-02-10 | Crystallizer vibration control device |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107448434A (en) * | 2017-09-26 | 2017-12-08 | 中冶赛迪工程技术股份有限公司 | A kind of continuous cast mold vibration energy saving servo hydraulic cylinder and hydraulic system |
| CN107816505B (en) * | 2017-10-19 | 2019-05-28 | 燕山大学 | A kind of active control hydraulic servo buffer |
| CN114603090B (en) * | 2022-03-11 | 2023-06-16 | 北京海卓博尔科技有限公司 | Crystallizer vibration driving device, control method and control system |
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