CN112775193A - Development and application technology of pressure closed-loop roll gap control technology for aluminum alloy cast-rolled plate - Google Patents
Development and application technology of pressure closed-loop roll gap control technology for aluminum alloy cast-rolled plate Download PDFInfo
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- CN112775193A CN112775193A CN202011572153.5A CN202011572153A CN112775193A CN 112775193 A CN112775193 A CN 112775193A CN 202011572153 A CN202011572153 A CN 202011572153A CN 112775193 A CN112775193 A CN 112775193A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/58—Roll-force control; Roll-gap control
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Abstract
The invention discloses a development and application technology of a pressure closed-loop roll gap control technology for an aluminum alloy cast-rolled plate, which controls the roll gap opening of an aluminum plate strip continuous casting-rolling machine through thickness AGC (automatic gain control), realizes high-speed rolling and accurate plate shape control, and produces a qualified thin strip cast-rolled plate. The invention has high automation degree, and the roll gap control and adjustment is simple, convenient and quick through the touch screen operation. Meanwhile, an advanced hydraulic AGC pressing system is adopted, and the control precision can reach 0.01 mm. The PLC is adopted to control the hydraulic pressure of the roller load oil cylinder, so that the consistency of the given rolling pressure and the plate thickness between the rolling load and an operator is realized.
Description
Technical Field
The invention relates to the technical field of aluminum alloy cast-rolling, in particular to a development and application technology of a pressure closed-loop roll gap control technology of an aluminum alloy cast-rolling plate.
Background
Since eighties, after the introduction of the first casting and rolling production line in China, along with the rapid development of economy and technology in China, the processing requirements on aluminum strips are more and more, and in the field of aluminum and aluminum alloy smelting, smelted aluminum liquid is usually conveyed from a smelting furnace to a casting and rolling machine through a launder to be cast and rolled so as to directly form aluminum strip plates. The roll gap between the casting rolls outside the aluminum casting and rolling mill is fixed, and the roll gap between the casting rolls is difficult to adjust according to aluminum materials with different sizes, so that the difficulty of aluminum material production and the cost of enterprises for producing aluminum materials with different sizes are increased.
Subsequently, with the progress of the equipment manufacturing technology, equipment manufacturers have provided a roll gap adjusting apparatus for an aluminum casting mill to solve the problem that it is difficult to adjust the roll gap between the casting rolls based on aluminum materials of different sizes because the size of the roll gap between the casting rolls outside the aluminum casting mill is fixed, which has been proposed in the above-mentioned technology. According to the roll gap adjusting device, the adjusting box body and the rotating gear are adopted, the rotating gear drives the adjusting box body to move, the convenience of adjusting the transverse distance between the driving roller and the driven roller is improved, and the difficulty in processing aluminum profiles of different sizes is reduced; the rotary screw rod and the sliding block are adopted, the screw block is driven by the rotary screw rod to adjust the height, the longitudinal distance between the driving roller and the driven roller is further adjusted, the convenience of height adjustment of the driven roller is improved, the sliding block is utilized to drive the other side of the sliding block to adjust the height, and the difficulty of height adjustment of the driven roller is reduced; adopt spacing piece and the limiting screw of supporting, fix thread piece and stopper through rotatory limiting screw, avoid stopper and thread piece to take place not hard up stability that influences the structure to through spacing friction that supports the piece increase junction, avoid the inside emergence of thread piece to slide.
However, in general, the roll gap adjusting device installed between the upper and lower roll bearing boxes is manually adjusted by workers in the production process, which is not only complicated and has the possibility of great error, but also has higher quality requirement on operators, and the most fundamental problem is that the roll gap real-time automatic compensation cannot be realized in the production process, and the whole roll of strip cannot be adjusted and changed once the thickness of the strip is set from the beginning of production.
Disclosure of Invention
The invention aims to provide a development and application technology of a pressure closed-loop roll gap control technology of an aluminum alloy cast-rolled plate, which is provided with a clean pressure oil source with stable pressure and enough flow for the pressure control of a rolling mill by adding an independent hydraulic pump station so as to meet the requirement of automatic control of the rolling thickness. The automatic oil-liquid separator is characterized in that two main pumps are arranged, one working pump is standby, the system is provided with an independent cooling and filtering loop, multi-stage filtering and magnetic filtering are realized, the cleanliness of oil is guaranteed, a heating device and a cooling device are further arranged, constant control over the oil temperature is realized, no-load starting and stopping can be realized, the service life of the pump is prolonged, the advantages of complete oil temperature, oil pressure, liquid level detection and alarming are achieved, manual adjustment through workers is achieved, the possibility of complexity and great error is overcome, the requirement on the quality of operators is high, the most fundamental problem is that real-time automatic compensation of roll gaps can not be achieved in the production process, and once the thickness of strips is set from the beginning of production, the whole roll of strips can not be adjusted and changed.
In order to achieve the purpose, the invention provides the following technical scheme: the closed-loop control structure of the development application technology of the pressure closed-loop roll gap control technology of the aluminum alloy cast-rolled plate is characterized in that:
a pressure control section: the actual rolling load is consistent with the rolling load given by an operator by adjusting the pressure of each side load oil cylinder;
a position control system: the roll gap corresponding to the outlet thickness given by the operator can be obtained, and the actual outlet thickness is equal to a given value;
a position AGC system: through a thickness error feedback control mode;
auxiliary functions: through two automatic and manual oil drainage modes, the load oil cylinder in the roller changing and emergency states can be reset to zero for fault protection.
As a further scheme of the invention, the bounce compensation of the rolling mill is carried out during the compensation control of the position of the roll gap and the pressure; the method is used for testing and fault finding of a rolling mill correction system during trial rolling.
As a further scheme of the invention, the position control can calculate a given roll gap through a bounce equation, and the actual roll gap is presented by changing the position of the hydraulic cylinder, and the bounce amount in the roll gap calculation is calculated according to the expected load and the actually measured rigidity of the rolling mill.
As a further scheme of the invention, the outlet thickness deviation is input into the position control system after control operation, and the position of the load oil cylinder is adjusted to eliminate the strip thickness difference.
As a further scheme of the invention, when the rolling mill is set to zero, the rollers synchronously move in the same horizontal state; during zeroing, the work rolls are pressed together under the zeroing load, the position of the load cylinder at this time is stored in the PLC for later control, and the position is used as the reference zero point of the roll gap.
The development and application technology of the pressure closed-loop roll gap control technology of the aluminum alloy cast-rolling plate is characterized in that aluminum liquid enters a given roll gap cast-rolling area to be rolled, crystallized and solidified, and finally the thickness actually obtained is just equal to the thickness given by an operator.
As a further aspect of the invention, the caster used must eliminate the traditional wedge adjustment and employ an AGC hydraulic reduction system.
As a further scheme of the invention, through hydraulic pressure reduction and position sensor feedback signal correction, the longitudinal thickness difference of the perimeter of the upper roll in the same length direction of the plate strip is as follows: less than or equal to 1.0 percent of H; the inclination of the thickness per meter is less than 0.5 percent; the longitudinal thickness difference of the whole length of the strip is less than or equal to 1.5 percent H.
Compared with the prior art, the invention has the following beneficial effects: the thickness of the cast-rolled finished product can be greatly reduced, the rolling speed can be increased, the thickness of the finished product can reach 2.0mm, and the highest rolling speed can reach 6 m/min.
(1) The automation degree is high, the operation is simple, and most functional computers finish the operation automatically.
(2) The display screen is clear and visual, the information is displayed by Chinese characters, and the display content is rich and easy to understand. And the touch screen is adopted for operation, so that the operation is convenient and fast.
(3) The control precision is high, and the same precision of the world advanced hydraulic AGC system can be achieved.
(4) The reliability is high, the PLC adopts imported products, and all components and parts adopt high-quality products in the world.
(5) The system response speed is fast.
Drawings
FIG. 1 is a schematic diagram of the AGC system elements of the present invention;
fig. 2 is an assembly diagram of the AGC crown control apparatus of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", "both ends", "one end", "the other end", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," "connected," and the like are to be construed broadly, such as "connected," which may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Example 1
Referring to fig. 1 and fig. 2, an embodiment of the present invention: the development and application technology of the pressure closed-loop roll gap control technology of the aluminum alloy cast-rolled plate is characterized in that the closed-loop control structure comprises the following steps:
a pressure control section: the actual rolling load is consistent with the rolling load given by an operator by adjusting the pressure of each side load oil cylinder;
a position control system: the roll gap corresponding to the outlet thickness given by the operator can be obtained, and the actual outlet thickness is equal to a given value;
a position AGC system: through a thickness error feedback control mode;
auxiliary functions: through two automatic and manual oil drainage modes, the load oil cylinder in the roller changing and emergency states can be reset to zero for fault protection.
The oil tank and the pipeline of the closed-loop control structure are all made of stainless steel materials, so that the working reliability is improved. The oil is filtered by three stages, wherein a filter with the diameter of 3 mu m is adopted in front of the servo valve, so that the cleanliness of the oil, the reliability of a system and the service life of the servo valve are improved. The system is provided with functions of overpressure overflow valve protection, pressure sensor alarm, interlocking and the like. The use is safe and reliable.
The hydraulic valve block is arranged at the upper part of the oil tank, and a pressure sensor, a servo valve, a filter and the like are arranged on the hydraulic valve block; the oil tank adopts stainless steel, realizes pressure measurement and the quick response of system. The oil cylinder is pressed up, and a position sensor is added to realize accurate position measurement.
The automatic thickness control system realizes thickness control by continuously adjusting the roll gap through a hydraulic control system or continuously adjusting the back tension or the rolling speed through a tension and speed adjusting system in an electric transmission system. The system is controlled by a Siemens S7-1500 programmable controller, and guarantees the long-term reliable operation of the system.
Molten aluminum in a molten state is controlled to enter a given roll gap between an upper roll gap and a lower roll gap through a casting nozzle, and a cast-rolling alloy plate with a fixed thickness requirement is formed through roll gap thickness adjustment in the cast-rolling process. And assembling the roller sleeve structure to a corresponding casting and rolling machine group to perform rolling forming on the molten aluminum alloy. After the rolling engagement is stable, the preloading force is increased to realize stable rolling, the thickness of the cast and rolled strip is directly increased, the rolling efficiency of the aluminum alloy is improved, and the crystallization quality and the stability of the plate shape are guaranteed.
Example 2
The embodiment provided by the invention comprises the following steps: the development and application technology of the pressure closed-loop roll gap control technology of the aluminum alloy cast-rolled plate is characterized in that a thickness automatic control system realizes thickness control by continuously adjusting the roll gap through a hydraulic control system, and the system has the following functions:
(1) pressure control
The pressure control is realized by adjusting the pressure of each side load cylinder to realize that the actual rolling load is consistent with the rolling load given by an operator, such as:
a. performing the bounce compensation of the rolling mill during the position and pressure compensation control;
B. the method is used for testing and fault finding of a rolling mill correction system during trial rolling;
C. monitoring a pressure limit;
D. and (5) zero setting of the rolling mill.
(2) Position control
The position of the hydraulic cylinder is controlled to obtain a roll gap corresponding to the outlet thickness given by an operator, when the outlet thickness and the expected load are given, a given roll gap can be calculated through a bounce equation, the roll gap is realized by changing the position of the hydraulic cylinder, and the bounce amount in roll gap calculation is calculated according to the expected load and the actually measured rigidity of the rolling mill.
(3) Position AGC
The position AGC is a thickness error feedback control mode, and is characterized in that outlet thickness deviation is input into a position control system after control operation, and the position of a load oil cylinder is adjusted to achieve the purpose of eliminating strip thickness difference.
The position AGC has a large adjusting range, the thickness range of the strip which is adapted to the position AGC is also large, and the position AGC is the most main AGC control mode of the strip mill.
(4) Auxiliary function
a. Oil drainage: under draining the oil state, the hydraulic oil in two load hydro-cylinders will be discharged, and after the hydro-cylinder decompression, there are two kinds of draining control methods: firstly, manual draining is used for roller changing and stopping, and secondly, automatic draining is used for fault protection under emergency conditions, for example, when a hard foreign body enters a rolling mill to cause the rolling pressure to exceed the limit.
b. Various physical parameters in the rolling process are displayed.
The method mainly comprises the following steps: rolling speed, rolling pressure, thickness deviation, roll gap on both sides and inclined pressure.
c. Synchronization of hydraulic cylinders: when the rolling mill is adjusted to zero, the rollers synchronously move in the same horizontal state, so that the rollers are prevented from generating indentation or damage.
d. Zero setting: and when the roll is changed, oil drainage or position control needs zero setting data, zero setting is carried out. During zeroing, the work rolls are pressed together under the zeroing load, the position of the load cylinder at this time is stored in the PLC for later control, and the position is used as the reference zero point of the roll gap.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Claims (8)
1. The closed-loop control structure of the development application technology of the pressure closed-loop roll gap control technology of the aluminum alloy cast-rolled plate is characterized in that: the closed-loop control structure:
a pressure control section: the actual rolling load is consistent with the rolling load given by an operator by adjusting the pressure of each side load oil cylinder;
a position control system: the roll gap corresponding to the outlet thickness given by the operator can be obtained, and the actual outlet thickness is equal to a given value;
a position AGC system: through a thickness error feedback control mode;
auxiliary functions: through two automatic and manual oil drainage modes, the load oil cylinder in the roller changing and emergency states can be reset to zero for fault protection.
2. The closed-loop control structure of the development and application technology of the pressure closed-loop roll gap control technology for the aluminum alloy cast-rolled plate as claimed in claim 1, wherein: performing the bounce compensation of the rolling mill during the compensation control of the position and the pressure of the roll gap; the method is used for testing and fault finding of a rolling mill correction system during trial rolling.
3. The closed-loop control structure of the development and application technology of the pressure closed-loop roll gap control technology for the aluminum alloy cast-rolled plate as claimed in claim 1, wherein: the position control can calculate a given roll gap through a bounce equation, and the actual roll gap is presented by changing the position of a hydraulic cylinder, wherein the bounce amount in the roll gap calculation is calculated according to the expected load and the actually measured rigidity of the rolling mill.
4. The closed-loop control structure of the development and application technology of the pressure closed-loop roll gap control technology for the aluminum alloy cast-rolled plate as claimed in claim 1, wherein: and (4) inputting the outlet thickness deviation after control operation into a position control system, and adjusting the position of the load oil cylinder to eliminate the thickness difference of the strip.
5. The closed-loop control structure of the development and application technology of the pressure closed-loop roll gap control technology for the aluminum alloy cast-rolled plate as claimed in claim 1, wherein: when the rolling mill is adjusted to zero, the rollers synchronously move in the same horizontal state; during zeroing, the work rolls are pressed together under the zeroing load, the position of the load cylinder at this time is stored in the PLC for later control, and the position is used as the reference zero point of the roll gap.
6. The development and application technology of the closed-loop control structure in the pressure closed-loop roll gap control technology of the aluminum alloy cast-rolling plate according to the claim 1, 2, 3, 4 or 5 is characterized in that: and (4) allowing the molten aluminum to enter a given roll gap casting area for rolling, crystallizing and solidifying, and finally obtaining the thickness which is exactly equal to the thickness given by an operator.
7. The development and application technology of the pressure closed-loop roll gap control technology for the aluminum alloy cast-rolled plate as claimed in claim 6, wherein the development and application technology comprises the following steps: the casting and rolling machine has to cancel the traditional wedge adjustment and adopt AGC hydraulic pressing system.
8. The development and application technology of the pressure closed-loop roll gap control technology for the aluminum alloy cast-rolled plate as claimed in claim 6, wherein the development and application technology comprises the following steps: through hydraulic pressure reduction and position sensor feedback signal correction, the longitudinal thickness difference of the perimeter of the upper roll in the same length direction of the plate strip is as follows: less than or equal to 1.0 percent of H; the inclination of the thickness per meter is less than 0.5 percent; the longitudinal thickness difference of the whole length of the strip is less than or equal to 1.5 percent H.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011572153.5A CN112775193A (en) | 2020-12-27 | 2020-12-27 | Development and application technology of pressure closed-loop roll gap control technology for aluminum alloy cast-rolled plate |
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| CN202011572153.5A CN112775193A (en) | 2020-12-27 | 2020-12-27 | Development and application technology of pressure closed-loop roll gap control technology for aluminum alloy cast-rolled plate |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114054554A (en) * | 2021-11-23 | 2022-02-18 | 北方工业大学 | Roll bending forming equipment auxiliary system capable of automatically adjusting roll gap |
| CN114535520A (en) * | 2022-03-03 | 2022-05-27 | 洛阳万基铝钛合金新材料有限公司 | Method for adjusting roll gap of casting and rolling machine without stopping |
| CN117862435A (en) * | 2024-03-11 | 2024-04-12 | 烟台一诺电子材料有限公司 | Aluminum strip casting forming device |
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| CN107138537A (en) * | 2017-06-08 | 2017-09-08 | 北京科技大学 | A kind of rolled aluminum sheet mill method for controlling thickness using electronic and hydraulic pressing |
| CN110181016A (en) * | 2019-05-27 | 2019-08-30 | 北京首钢国际工程技术有限公司 | A kind of big pressure casting and rolling machine of the box-like heavy slab of 2+8 roller group |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114054554A (en) * | 2021-11-23 | 2022-02-18 | 北方工业大学 | Roll bending forming equipment auxiliary system capable of automatically adjusting roll gap |
| CN114535520A (en) * | 2022-03-03 | 2022-05-27 | 洛阳万基铝钛合金新材料有限公司 | Method for adjusting roll gap of casting and rolling machine without stopping |
| CN114535520B (en) * | 2022-03-03 | 2024-05-03 | 洛阳万基铝钛合金新材料有限公司 | Method for adjusting roll gap of casting and rolling machine without stopping |
| CN117862435A (en) * | 2024-03-11 | 2024-04-12 | 烟台一诺电子材料有限公司 | Aluminum strip casting forming device |
| CN117862435B (en) * | 2024-03-11 | 2024-05-28 | 烟台一诺电子材料有限公司 | Aluminum strip casting forming device |
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