JPS58199613A - Method and device for controlling coiling temperature at transformation in hot rolling mill - Google Patents

Abstract

PURPOSE:To perform titled temperature control, by spraying water onto a strip under conditions of including the data on the temperature distribution of a strip detected by several kinds of detectors and the data on the several conditions of transformation depending on the several kinds of steels. CONSTITUTION:In hot rolling a carbon steel containing 0.10-1.7% carbon or an alloy steel, the temperature distribution of a strip 4, moving from a hot finishing mill 1 to a coiler 3 through a cooling device 2, is detected by a thermometer 5 at the exit of the mill 1, intermediate thermometers 6, and a thermometer 7 at the front of the coiler 3. These detected values, and the heat capacity of transformation, the starting temperature of the transformation, and the time of the transformation depending respectively on the kinds of steels are included into the conditions of water cooling spraying cooling water from nozzles 9 onto the strip 4. Thus, by controlling the positions of starting and completing the transformation to an optional position, the temperature distribution of the strip 4 at the coiler 3 is controlled to be in an untransformed state, under transformation, and a completely transformed state, and further, the starting of transformation is controlled at the position of the thermometer 6.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a transformation winding a! which is most suitable for hot rolling materials.
In order to set the degree, we can understand the changes in the transformation state of each steel type based on various measurement data (), and we can control the transformation start point and transformation completion point of each rope to the desired position.Transformation winding in the hot rolling mill The present invention relates to a temperature control method and device.

In general, during hot rolling of carbon steel and alloy steel, the hot rolled steel material after exiting the finishing mill is cooled to a transformation temperature point at which the iron austenite structure transforms into the iron pearlite structure. When this happens, an exothermic phenomenon occurs due to metamorphosis. The calorific value of this transformation is primarily determined by the carbon content, but it also depends on the use of the material.

The place where metamorphosis starts and the place where metamorphosis is completed vary depending on the destination.

Taking this situation as an example based on Figures 1 to 4, the untransformed winding temperature control shown in Figure 1 extends the incubation time in order to obtain a coarse pearlite structure, and the transformation starts after the winding point 1.1. The winding temperature control during the f state in Fig. 2 is to start the transformation at lnJ 11 at the winding humidity needle in order to obtain a spherical pearlite structure, and to control the winding temperature during the f state in Fig. 3.
'The winding temperature control is performed by changing the winding temperature needle at the winding temperature needle in order to obtain a fine pearlite structure, and then winding is performed after the transformation is completed. degree tIII11
In order to obtain a homogeneous pearlite structure, 11 controls the transformation temperature to be maintained at a substantially constant level immediately after the direction change starts at the intermediate thermometer and the transformation is completed at the winding humidity needle.

Despite the fact that the transformation state varies depending on the type of steel, in conventional hot rolling, operations were carried out by controlling only the target winding humidity, so as can be seen in the above drawing, the transformation condition B + There were 3 points where the temperature was the same, and the operator was winding without knowing whether the temperature was in the 3 transformation states, i.e., untransformed, undergoing transformation 1, or completed transformation, resulting in variations in the steel structure and uniformity. This was an obstacle to obtaining products with good mechanical properties.

The present invention is such a jl! The temperature distribution and winding temperature at each part of the strip and knob that moves through the hot run table after passing through the L rolling mill and the winding temperature are adjusted to adjust the winding temperature according to the intended use and destination of the finished product. The present invention provides a method and apparatus for controlling variable winding aa degree, in which cooling water is injected into the strip at any time in order to control the humidity and transformation state of the strip.

EMBODIMENT OF THE INVENTION The transformation coiling temperature control method and device for a hot rolling mill according to the present invention will be explained based on the drawings.

Along the moving direction of the strip 4, there is a hot rolling finishing mill 1, a cooling device 21, a winding device! i13 and No.
Behind the finishing mill 1 and the cooling device 2, which are made up of stands No. 1 to No. 6, are a pulse transmitter 19 attached to the No. 5 stands, a thickness needle 20, and a strip temperature measuring device. Thermometers 5 on the utility output side are placed at 11R, respectively.

In addition, each water injection nozzle 9 that supplies water to the water injection banks 8, 8, which are distributed between the hot run tables 21 in the cooling device 2 above and below, is provided with a water source control valve 10, so that the water flow can be freely controlled, and the water can be cooled as well. An intermediate thermometer 6 for strip heating is installed at any intermediate location within the device 2.

Furthermore, a Tani Tori thermometer 7 is installed in the darkness between the cooling bag r2 and the winding device 13, and the initial setting device 11 is used for control based on the data of each god ml device. ．． Upper computer 2. Cooling information receiving device 11113. Required bank number calculation device 14. Water injection matrix creation device 11
15. Water injection bank control device 716° feedback control device 17. The learning device 18 and the like are provided to configure variable winding standard control vk* in the hot rolling mill.

Here, the model of humidity drop for each spear due to cooling at each moving position of the rope is as follows.

1. Temperature drop model in the air cooling area d6 13 4 dt-h"θ+273) 4 At - (#A+273) ) - (θ-θA) - Aλ , (θ-θl') 1" P 2, In the water region Temperature drop model do Am A7 dt""k"θ-θg)-(o-θW)A-,-(#-θm>10'! p 3, Temperature drop model in the water-cooled region of the lower bank only f
=-ri ((θ+273)' 4 At -(θA+273) ,)-'j (θ-θ^)A
t h-(lj Ow) + ru-2 However, θ:
Material temperature °C, IH time set, B: radiation constant / z #
, 7 # t 3 , A l : Lower bank water cooling constant ″j 1/ , , , , , A , , air cooling constant 11/.

,,,Al: Heat transfer chamber 11!19' to table roller
/ j I (I θ^: temperature ℃, ni: Itagishikai, 91
: Metamorphosis heat generated per unit time. 3.8c
al ,,,C: specific heat /,,ρ: ratio 11 f/*3+
A'': upper bank water cooling constant, θW: water at 4°C.

In addition, the coefficients of the model equation are B, A, A I A r ,
Al was determined by off-line calculation of actual operation data, and 1
'1 The transformation a momentum is determined by the transformation time, which is determined by the steel type and the transformation start temperature, and -
It is calculated from the total heat value of metamorphosis that depends only on the bridge.

Even more strange - the start timing is constantly changing MANN
The required data for each embroidery value obtained in this manner is inputted into the cooling information receiving device 13 as the cooling information and transformation information of the strip 4.

In carrying out the actual transformation winding m+r control,
When the moving strip 4 is put into the No. 1 stand of the finishing rolling mill 1, the initial setting device 11 is activated.
Cooling information received value 1111 via host computer 12
Based on the various cooling information of the strip 4 and the V-opening information received by the controller 3, the tip part number of the strip 4 calculates the necessary water injection bank disease and water injection pattern.

Then, the water injection bank control value *16 is activated to command the upper and lower water injection banks 8.8 in the four-side cooling device 2 to open and close the water break control valve 1° installed in each water nozzle 9. Output.

Furthermore, the number of the finishing pressing machine 1 is
, 6, the pulse compensator 19 generates a compensator signal for every fixed length pitch, and the required bank number calculating device 14 is activated.

At this point, the finishing exit temperature needle 5. Nakayami Oni total 6I
Each temperature in the winding thermometer 7 and other materials.

Based on the cooling information of the cooling information receiving device 13 that takes into account the data of each apple that measures the board, water injection pattern, etc., and the changing planer information, calculate the required number of water injection banks directly below the finish exit side thermometer 5, and then perform the following steps. When bank response delay 1 passes due to water injection matrices and sox making device 15, lII! A water injection matrix is created taking into account the above factors, and the water injection puncture control value -16 is activated to output an opening/closing command for the water capacity control valve lO as described above.Furthermore, the movement of the strip 4 progresses, and its tip reaches the winding temperature 9 meter. When the temperature reaches 7, the feedback opening/opening device 17 is activated to control the winding thermometer 7 so that it reaches the target winding temperature 1. Further, the learning device 9 is operated to appropriately mill the variation between the coils.

In this way, cooling water is injected into the strip 4 by taking into account the measurement data of each loincloth measurement device and the data of each metamorphosis state by each type II of the MY distribution of the strip 4. It is designed to freely control the metamorphosis heat generation phenomenon.

As mentioned above, the transformation coiling temperature in the hot rolling mill according to the present invention! Method 4 is a method of hot rolling carbon steel or copper alloy with a carbon content of 010 to 1,7 shea, from a hot rolling finishing mill 1 to a cooling device 2 to a winding machine 3. Finish the temperature distribution of the moving strip 4 with the temperature needle on the exit side 5.
Transformation is started by pouring cooling water into the strip 4, which is measured by the intermediate degree meter 61 and winding temperature needle 7 in the cooling device 2, and further takes into account the transformation heat capacity, transformation start humidity, and transformation time, which depend on the steel type. The temperature distribution in the winder 3 is controlled to be in the untransformed state, in the transformation state, and in the f-transformation completed state, and the transformation starts at the position of the intermediate thermometer. It is something to do.

Similarly, the transformation coiling temperature control device is installed in the hot ductility top rolling mill l located along the moving direction of the strike IJ tube 4.
Strip il! between the cooling device 2 and the cooling device 2! A finished steel tapping thermometer 5 for measuring If is provided, and an intermediate thermometer 6 in the cooling device for measuring strip humidity is provided at an arbitrary point in the middle of the cooling device 2,
Furthermore, a winding thermometer 7 is provided between the cooling device 2 and the winding machine 3,
In addition, a water injection puncture control device 16 that controls the flow rate of water for each water injection nozzle 9 in the cooling system 2 @ the water flow rate of the control valve lO is connected to the finishing outlet side thermometer 5. The intermediate temperature needle 61 is configured to receive a signal from the winding temperature gauge 7.

By controlling the transformation coiling temperature during hot rolling, the present invention guarantees the hardness desired by the user in the untransformed and transformed coiling temperature control numbers, and the shearing of the finished product in the transformation completed coiling temperature control. It improves workability, and also eliminates some cold rolling processes and TOP annealing.It is also effective against coil deformation, reducing coil deformation from 15% to 0.3 in total production. %, and further improves the mechanical properties of the product, such as the ability to omit the heat treatment process, as it has the effect of changing the structure to a tough and fine structure similar to that of patenting treatment on a transformation table. It has many excellent effects in measuring the improvement of

[Brief Description of the Drawings] The drawings show an embodiment of the transformation coiling temperature control method and device in a hot rolling mill according to the present invention.
Figures 4 to 4 are for explaining the changes in each brown transformation state due to cooling of general hot-rolled steel. Figure 1 shows untransformed winding, Figure 2 shows winding in the transformation range, Figure 3 shows transformation completed winding, and Figure 4 explains transformation completed winding, and the winding points in each temperature/degree control. , FIG. 5 is a schematic diagram illustrating the entire transformation winding and knitting control method and apparatus. 1 Hot rolling finishing mill 2 Cooling device 3 Winding device 4 Strip 5 Finishing flange humidity needle 6 Intermediate thermometer 7 Winding temperature needle 9 Water injection nozzle 10 Water volume 1+ll valve patent Out - person Nikko Steel Co., Ltd.
Others^6] Representative Patent attorney Furu
1) Keita Tsuyoshi 1 Figure 2 3'l (乍や) 7-I *3 Prisoner 6 + ■ Continued from page 1 0 Inventor Toshihiko Kato 1-29-35 Honmachi, Asaka City 0 Inventor Person: 1-26-2 Honjuku-cho, Fuchu-shi, Tokyo 0 Person: Seiji Fukuda 6-32, Sagami-ga-oka, Zama-shi ■Applicant: Tokyo Shibaura Electric Co., Ltd. 72, Horikawa-cho, Saiwai-ku, Kawasaki-shi

Claims (1)

[Claims] 1. In a method of hot rolling carbon steel or alloy steel with a carbon content of 0.10 to 17%, hot rolling finish I11: from the rolling machine to the winding machine I through the cooling device. 1) The temperature distribution of the strip is measured by the humidity needle on the finish exit side, the temperature needle in the center of the cooling device, and the temperature needle for one winding. Start a! Every time. Taking into account the transformation time, the cooling water is supplied to the strip, thereby controlling the transformation start location, the xmaer field Wt, to an arbitrary location, and leaving the knitting portion in the winding machine in an untransformed state. Metamorphosis in progress, metamorphosis complete state [LF metamorphosis begins at the position of the middle temperature needle and the position of the middle temperature needle, which stretches one time! , il ml. 2. Install an AM111 gauge on the finishing outlet side for measuring the strip temperature between the hot-rolling finishing mill and the cooling device in the middle of the power distribution along the direction of strip movement, and install the strip temperature meter at an arbitrary point in the middle of the cooling device. Equipped with a thermometer inside the regular cooling system, cooling 4II! A winding humidity needle is provided between the winder and the winder, and a water injection bank IJ111111 device that controls the temperature of the flowing water of the water flow control valve for each water injection nozzle in the cooling device is installed on the finishing exit side knitting needle, intermediate @ degree. Transformation winding temperature in a hot rolling mill, where the device is configured to receive a signal from a total of one winding thermometer.