CN115254974A - A heating device for work rolls - Google Patents

Abstract

A heating device for a work roll, comprising a plurality of temperature sensors, spray heads, and a control system; the plurality of temperature sensors are arranged along the axial direction of the work roll to sense the roll surface temperature of each section of the work roll; the plurality of spray heads are respectively connected to the Each section of the work roll corresponds to each section, and each nozzle is connected to the heat medium pipeline and the cold medium pipeline through an electromagnetic throttle valve; the control system is connected to a temperature sensor and an electromagnetic throttle valve, which can be adjusted according to the roll surface temperature of each section of the work roll. The flow rate of each electromagnetic throttle valve enables each nozzle to spray media with different temperatures to heat or cool the corresponding work roll section. The invention can solve the problem of uniform preheating of the work rolls before rolling; in the rolling process, the temperature gradient can be eliminated, so that the upper and lower work rolls can maintain the original middle crown, and the rolling quality of the strip can be guaranteed; After the design deviation occurs in the middle convexity of the plate, the invention can also compensate for the defect of the middle convexity through the temperature deviation, so as to obtain a better plate shape.

Description

A heating device for work rolls

technical field

The invention relates to the technical field of aluminum strip rolling, in particular to a heating device for work rolls.

Background technique

Wide and thin aluminum alloy strips will have tight edges during cold rolling. The reason is that during the rolling process of the work rolls and the strip, the temperature rises in the middle area of the work rolls, while the temperature rises at the two sides are low, and the temperature is gradient. distribution, resulting in a tight edge at the edge of the strip. The tight edge phenomenon will not only cause poor strip shape and edge cracks, but also cause strip breakage, especially for high-grade aluminum alloy strips rolled at high speeds, strip breakage often occurs, seriously affecting the normal rolling production . The essence of tight edge phenomenon is that the appearance of temperature gradient causes the thermal expansion and contraction of the work roll, which increases the original crown of the work roll, making the strip thinner in the middle and thicker on both sides.

The current solution is to heat both sides of the work rolls to ease the temperature gradient. The existing problem is that the heating of the edge of the work roll depends entirely on experience and cannot be accurately controlled, causing the heating temperature to be too high or insufficient, and the temperature gradient cannot be completely eliminated.

Contents of the invention

In order to overcome the deficiencies in the background technology, the invention discloses a heating device for working rolls, the purpose of which is to eliminate the temperature gradient of the working rolls and solve the problem of edge tightness.

In order to realize the above-mentioned purpose of the invention, the present invention adopts following technical scheme:

A heating device for work rolls, comprising:

A plurality of temperature sensors, arranged along the axial direction of the work roll, are used to sense the roll surface temperature of each section of the work roll;

A plurality of nozzles correspond to each section of the work roll, and each nozzle is connected to the hot medium pipeline and the cold medium pipeline through an electromagnetic throttle valve;

The control system is connected with the temperature sensor and the electromagnetic throttle valve. The control system can adjust the flow rate of each electromagnetic throttle valve according to the roll surface temperature of each section of the work roll, so that each nozzle sprays out media with different temperatures to heat or cool its parts. Corresponding work roll section.

To further improve the technical solution, the temperature sensor is an infrared sensing temperature sensor.

To further improve the technical solution, the heat medium pipeline is connected to the heating box, and the heating box is used to inject heat medium into the heat medium pipeline.

To further improve the technical solution, the cold medium pipeline is connected to a refrigeration box, and the refrigeration box is used to inject cold medium into the cold medium pipeline.

To further improve the technical solution, the medium is rolling oil or air.

Due to the adoption of the above technical solution, compared with the background technology, the present invention has the following beneficial effects:

1. The present invention can solve the problem of uniform preheating of work rolls before rolling;

2. During the rolling process, the present invention can eliminate the temperature gradient, keep the upper and lower work rolls at the original crown, and ensure the rolling quality of the strip;

3. When the design deviation of the crown of the work roll occurs, the present invention can compensate the design defect of the crown through the temperature deviation, so as to obtain a better plate shape.

Description of drawings

What Fig. 1 shows is the structural representation of the present invention.

FIG. 2 shows a side view of FIG. 1 .

Figure 3 shows a schematic diagram of the workflow of the present invention.

In the figure: 1. Work roll; 2. Backup roll; 3. Strip; 4. Temperature sensor; 5. Nozzle; 6. Electromagnetic throttle valve; 7. Hot medium pipeline; 8. Cold medium pipeline; 9. Heating box; 10. Cooling box; 11. Collection box; 12. Spray area.

Detailed ways

Preferred embodiments of the present invention are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention, and are not intended to limit the protection scope of the present invention. It should be noted that, in the description of the present invention, the terms "front", "rear", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", Terms such as "outside" and other indicated directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, use a specific Azimuth configuration and operation, therefore, should not be construed as limiting the invention. It should also be noted that, in the description of the present invention, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be interpreted in a broad sense, for example, it can be a fixed connection or a flexible connection. Detachable connection, or integral connection; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary, or the internal communication of two components. Those skilled in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

A heating device for work rolls is arranged on a rolling mill. The rolling mill has a pair of work rolls 1 and a pair of back-up rolls 2 for rolling aluminum strips 3 . The heating device mainly includes 12 temperature sensors 4, 12 nozzles 5, and a control system. Its structure and function are described in detail below.

As shown in Figure 1-2, 12 temperature sensors 4 are arranged along the axial direction of the work roll 1, among which 6 are arranged on the upper work roll 1 and 16 are arranged on the lower work roll. The temperature sensor 4 divides the upper work roll 1 and the lower work roll 1 into 6 sections respectively, and is used to sense the roll surface temperature of each section of the upper and lower work roll 1 . In this embodiment, the temperature sensor 4 is an infrared temperature sensor 4, which has the advantages of high sensitivity and non-contact measurement. In particular, the infrared temperature sensor 4 can convert temperature information into electrical signals, so as to communicate with the control system.

The 12 nozzles 5 correspond to the 6 sections of the upper and lower work rolls 1 respectively. It can be seen from FIG. Axial. Each spray head 5 is connected to the heat medium pipeline 7 and the cold medium pipeline 8 through two electromagnetic throttle valves 6 respectively. Wherein, the heat medium pipeline 7 is connected with a heating box 9 , and the heating box 9 is used for injecting heat medium into the heat medium pipeline 7 . The cooling medium pipeline 8 is connected to the refrigeration box 10 , and the refrigeration box 10 is used for injecting the cooling medium into the cooling medium pipeline 8 . In this embodiment, the medium is rolling oil. Rolling oil is a lubricating medium that must be used in the cold rolling process. In the invention, rolling oil is also used as a heat transfer medium. The heating box 9 can heat the rolling oil to make the temperature of the rolling oil reach 260°C. The refrigeration box 10 can cool the rolling oil so that the temperature of the rolling oil can reach -10°C. The opening size of the two electromagnetic throttle valves 6 determines the injection volume and mixing ratio of the hot rolling oil and the cold rolling oil.

As shown in Figure 3, the control system is connected with each temperature sensor 4 and each electromagnetic throttle valve 6, and the control system can adjust the flow rate of each electromagnetic throttle valve 6 according to the roll surface temperature of each section of the work roll 1, so that each nozzle 5 sprays Different temperature media are used to heat or cool the corresponding work roll 1 section. The control system can be a control system with PLC as the core, or a control system with PID control as the core. Both the background of PLC and PID are editable.

In order to recover and utilize the sprayed rolling oil, a rolling oil collection box 11 is provided below the rolling mill. The rolling oil enters the collection box 11 and after being filtered in the collection box 11, it is pumped into the heating box 9 and the refrigeration box 10 respectively for reuse.

It is worth noting that the medium can also be air. The hot and cold air can also cool and heat the work roll 1 without causing environmental pollution. However, the heat capacity of air is smaller than that of rolling oil, and the cooling or heating effect is not as good as that of rolling oil.

work process:

For the rolling of the aluminum strip 3, the upper and lower work rolls 1 must be preheated before rolling. At this time, the control system strictly controls the injection ratio of hot and cold rolling oil from each nozzle 5, so that the rolling oil injected from each nozzle 5 has the same temperature, and the upper and lower work rolls 1 are evenly heated. In this way, the crown of the upper and lower work rolls 1 remains unchanged.

After starting rolling, the upper and lower work rolls 1 begin to have a gradient change, and the temperature in the middle area of the upper and lower work rolls 1 is higher than that at both sides. At this time, 12 temperature sensors 4 collect and upload the temperature of each section of the upper and lower work rolls 1 . After knowing the temperature information of each section of the upper and lower work rolls 1, the control system adjusts the proportion of cold rolling oil correspondingly to the nozzle 5 located in the middle area of the work roll 1, reduces the spraying temperature of the rolling oil, and controls the temperature of the area. cool down. For the nozzle 5 located in the edge area of the work roll 1, the ratio of the hot rolling oil is increased accordingly, the injection temperature of the rolling oil is increased, and the area is heated. In other transitional areas, the injection temperature should also be adjusted appropriately. Its purpose is to make the roll surface temperature of each section of the upper and lower work rolls 1 basically consistent, eliminate the temperature gradient, and ensure the original crown of the upper and lower work rolls 1 .

In another case, sometimes even if the upper and lower work rolls 1 maintain the original crown, the rolled aluminum strip 3 still has tight edges or other problems, which shows that the designed crown of the upper and lower work rolls 1 is related to rolling Condition did not match. At this time, by adjusting the background of PLC or PID, the spraying temperature of each nozzle 5 can be adjusted accordingly, and the temperature of each section of the work roll 1 can be intentionally different, so that the crown of the work roll 1 can be changed accordingly, so as to obtain a better shape of the plate. For example, the crown design is small, in order to compensate for the crown, for the nozzle 5 located in the middle area of the work roll 1, the ratio of the hot rolling oil is increased accordingly, the injection temperature of the rolling oil is increased, and the area is heated , so that the actual crown of the work roll 1 increases. Furthermore, the design of the crown is large. In order to reduce the crown, for the nozzle 5 located at the edge of the work roll 1, the ratio of the hot rolling oil is increased accordingly, the injection temperature of the rolling oil is increased, and the area is heated. , so that the actual crown of the work roll 1 is reduced.

As can be seen from the above, the present invention can solve the problem of uniform preheating of the work rolls 1 before rolling; during the rolling process, the temperature gradient can be eliminated, so that the upper and lower work rolls 1 can maintain the original crown, ensuring the uniformity of the strip 3. Rolling quality; when the crown of the work roll 1 deviates from the design, the present invention can also make up the defect of the crown through the temperature deviation, so as to obtain a better plate shape.

The parts not described in detail are prior art. Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes, modifications and substitutions can be made to these embodiments without departing from the principle and spirit of the present invention. and modifications, the scope of the present invention is defined by the appended claims and their equivalents.

Claims (5)

1. A heating device for work rolls, characterized in that: comprising: A plurality of temperature sensors, arranged along the axial direction of the work roll, are used to sense the roll surface temperature of each section of the work roll; A plurality of nozzles correspond to each section of the work roll, and each nozzle is connected to the hot medium pipeline and the cold medium pipeline through an electromagnetic throttle valve; The control system is connected with the temperature sensor and the electromagnetic throttle valve. The control system can adjust the flow rate of each electromagnetic throttle valve according to the roll surface temperature of each section of the work roll, so that each nozzle sprays out media with different temperatures to heat or cool its parts. Corresponding work roll section. 2. A heating device for work rolls according to claim 1, characterized in that: the temperature sensor is an infrared temperature sensor. 3. A heating device for work rolls according to claim 1, characterized in that: the heat medium pipeline is connected to a heating box, and the heating box is used to inject heat medium into the heat medium pipeline. 4. A heating device for work rolls according to claim 1, characterized in that: the cold medium pipeline is connected to a refrigeration box, and the refrigeration box is used to inject cold medium into the cold medium pipeline. 5. A heating device for work rolls according to claim 1, characterized in that: said medium is rolling oil or air.

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