Automatic control method for outlet width of hot rolling roughing mill

Abstract

The invention relates to an automatic control method for the outlet width of a hot-rolling roughing mill, and belongs to the technical field of steel machining. Comprising the following steps that the R1 last-pass width average value WAVG and the R1 last-pass full-length width minimum value WMIN in the rolling process of a roughing mill are collected; the collected data are judged, if the conditions are not met, rolling is carried out normally, and if the conditions are met, outlet width compensation is carried out; the method comprises the steps that firstly, a target width compensation value A is calculated, then the target width compensation value A and a final-pass target width value WAIM are added to obtain a final width target value WNEW of the final pass, a roughing mill R2 area is set according to the WNEW, and then the steel-making plate special-shaped blank is rolled according to the WNEW. According to the method, on the premise that new equipment is not added, automatic control over the outlet width (the width of the last pass of the second pair of vertical rollers in the roughing mill R2 area) in the rolling process of the steel-making plate special-shaped blanks of different sizes is achieved, and the problem of width degradation occurring in the roughing process of existing steel-making plate special-shaped blanks is solved.

Description

Technical Field

[0001] The present invention relates to an automatic control method for the outlet width of a hot rolling roughing mill, belonging to the technical field of steel processing. Background Art

[0002] During the production of strip steel by hot continuous rolling, in order to pursue the ultimate cost and efficiency, the width adjustment conditions during the casting process of steel slabs are continuously relaxed, resulting in an increasing number of width-adjusted slabs. At the same time, the variation range of the shaped slabs of the slabs is getting larger and larger. When these width-adjusted shaped slabs are rough-rolled on the hot rolling roughing mill, a width degradation phenomenon will occur. Through the analysis of the entire roughing process, it is found that increasing the appropriate outlet width of the roughing mill when the width degradation of the shaped slab occurs can greatly improve the width degradation problem. Therefore, the engineers summarized the reason for the width degradation problem of the shaped slab during rough rolling as follows: the set outlet width of the hot rolling roughing mill (i.e., the width of the last pass in the roughing R2 area) is smaller than the actual required outlet width of the shaped slab. Therefore, how to appropriately control the outlet width of the hot rolling roughing mill has become the key to solving the width degradation problem of the shaped slab during rough rolling. Most of the existing technologies adopt the following methods: 1. Add the identification of the shaped slab of the slab in the rolling plan information. After seeing the identification, the operator increases the target value of the outlet width of the roughing mill in advance according to experience; however, this method requires manual adjustment according to experience and inaccurately controls the outlet width of the hot rolling roughing mill. 2. Add a pressure width setter in front of the roughing R1 to restore the shaped slab to a normal slab for rough rolling; this method requires a relatively high equipment cost. Summary of the Invention

[0003] The technical problem to be solved by the present invention is: how to automatically control the outlet width of the hot rolling roughing mill without adding equipment.

[0004] The technical solution proposed by the present invention is: an automatic control method for the outlet width of a hot rolling roughing mill, including the following steps:

[0005] Step 1: Set the target width values of each pass of the first opposing rolls in the roughing mill R1 area and the target width values of each pass of the second opposing rolls in the R2 area; collect the average width W of the last pass in the roughing mill R1 area during the rolling process of the shaped slab of the steel slab in the roughing mill R1 area AVG and the minimum full-length width W of the last pass in the roughing mill R1 area MIN ;

[0006] Step 2: Substitute the data collected in Step 1 into the following formula (1) for judgment,

[0007]

[0008] In formula (1), a is an empirical value, and its value range is an integer between 2 mm and 8 mm; WLAST is the target width value W of the last pass set in the roughing mill R1 area LAST ;

[0009] If any of the data collected in step 1 does not satisfy any of the formulas (1), the rolling process of the special-shaped billet of the steel plate in the roughing mill R2 area is completed according to the target width values of each pass of the second opposing rolls in the roughing mill R2 area set in step 1; if the data collected in step 1 satisfies the formula (1), proceed to the next step;

[0010] Step 3: Calculate the target width compensation value A of the last pass in the roughing mill R2 area through the following formula (2),

[0011]

[0012] In formula (2), L is the width compensation coefficient, which is an empirical value, and its value range is from 0.5 to 1;

[0013] When the special-shaped billet of the steel plate is transported from the roughing mill R1 area to the R2 area, the target width value W of the last pass of the second opposing rolls in the R2 area AIM is compensated to obtain the final width target value W of the last pass in the roughing mill R2 area NEW ;

[0014] The compensation process is as follows: Add the target width compensation value A of the last pass in the roughing mill R2 area to the target width value W of the last pass of the second opposing rolls set in step 1 AIM to obtain the final width target value W of the last pass in the roughing mill R2 area NEW ;

[0015] After the compensation is completed, the target width value of the last pass of the second opposing rolls in the roughing mill R2 area is set according to the W NEW and then the special-shaped billet of the steel plate is rolled according to the W NEW For rolling.

[0016] Furthermore, when the target width compensation value A of the last pass in the roughing mill R2 area in step 3 is greater than the target width correction value B of the last pass in the roughing mill R2 area, adjust the target width compensation value A of the last pass in the roughing mill R2 area to the target width correction value B of the last pass in the roughing mill R2 area. The target width correction value B of the last pass in the roughing mill R2 area is an empirical value, and its value range is an integer between 0 mm and 8 mm.

[0017] Advantages of the present invention: Without adding new equipment, the present invention determines whether the width control of the outlet of the roughing mill is required by collecting data of the profiled billet of steel plate during rolling in the R1 area of the roughing mill. If width control is required, width compensation is performed on the outlet width of the roughing mill to meet the rolling requirements of the profiled billet of steel plate, realizing the automatic control of the outlet width (the width of the last pass of the second opposing rolls in the R2 area of the roughing mill) during the process of the roughing mill rolling profiled billets of steel plates with different sizes without human intervention, and greatly alleviating the problem of width degradation of the existing profiled billets of steel plate during rough rolling. Specific embodiments

[0018] The following further describes an automatic control method for the outlet width of a hot rolling roughing mill according to the present invention in conjunction with embodiments

[0019] An automatic control method for the outlet width of a hot rolling roughing mill includes the following steps:

[0020] Step 1: Set the target width values of each pass of the first opposing rolls in the R1 area of the roughing mill and the target width values of each pass of the second opposing rolls in the R2 area; collect the average width W of the last pass in the R1 area of the roughing mill during the rolling process of the profiled billet of steel plate in the R1 area of the roughing mill AVG and the minimum full-length width W of the last pass in the R1 area of the roughing mill MIN ;

[0021] Step 2: Substitute the data collected in Step 1 into the following formula (1) for judgment,

[0022]

[0023] In formula (1), a is an empirical value, and its value range is an integer between 2 mm and 8 mm; W LAST is the set target width value W of the last pass in the R1 area of the roughing mill LAST ;

[0024] If the data collected in Step 1 does not meet any of the conditions in formula (1), the rolling process of the profiled billet of steel plate in the R2 area of the roughing mill is completed according to the target width values of each pass of the second opposing rolls in the R2 area of the roughing mill set in Step 1; if the data collected in Step 1 meets formula (1), proceed to the next step;

[0025] Step 3: Calculate the target width compensation value A of the last pass in the R2 area of the roughing mill through the following formula (2),

[0026]

[0027] In formula (2), L is the width compensation coefficient, which is an empirical value, and its value range is 0.5 to 1;

[0028] If the target width compensation value A for the last pass in the roughing mill R2 area is greater than the target width correction value B for the last pass in the roughing mill R2 area, then adjust the target width compensation value A for the last pass in the roughing mill R2 area to the target width correction value B for the last pass in the roughing mill R2 area. The target width correction value B for the last pass in the roughing mill R2 area is an empirical value, and its value range is an integer between 0 mm and 8 mm.

[0029] When the special-shaped billet of the steel plate is transported from the roughing mill R1 area to the R2 area, the target width value W for the last pass of the second opposing roll in the R2 area AIM is compensated to obtain the final width target value W for the last pass in the roughing mill R2 area NEW ;

[0030] The compensation process is as follows: Add the target width compensation value A for the last pass in the roughing mill R2 area to the target width value W for the last pass of the second opposing roll set in step 1 AIM to obtain the final width target value W for the last pass in the roughing mill R2 area NEW ;

[0031] After the compensation is completed, the target width value for the last pass of the second opposing roll in the roughing mill R2 area is set according to W NEW and then the special-shaped billet of the steel plate is rolled according to W NEW .

Claims

1. An automatic control method for the outlet width of a hot rolling roughing mill, characterized in that: It includes the following steps: Step 1: Set the target width values for each pass of the first opposing rolls in the roughing mill R1 area and the target width values for each pass of the second opposing rolls in the R2 area; collect the average width W of the last pass in the roughing mill R1 area and the minimum full-length width W of the last pass in the roughing mill R1 area during the rolling process of the special-shaped billet of the steel plate in the roughing mill R1 area AVG and the minimum full-length width W of the last pass in the roughing mill R1 area MIN ; Step 2: Substitute the data collected in Step 1 into the following formula (1) for judgment. In formula (1), a is an empirical value, and its value range is an integer between 2 mm and 8 mm; W LAST is the target width value of the last pass set in the R1 area of the roughing mill W LAST ; If the data collected in Step 1 does not meet any of the formulas in formula (1), the rolling process of the special-shaped billet of the steel plate in the R2 area of the roughing mill is completed according to the target width values of each pass of the second opposing rolls in the R2 area of the roughing mill set in Step 1; if the data collected in Step 1 meets formula (1), proceed to the next step; Step 3: Calculate the target width compensation value A for the last pass in the R2 area of the roughing mill through the following formula (2). In formula (2), L is the width compensation coefficient, which is an empirical value, and the value range is from 0.5 to 1. When the special-shaped billet of the steel slab being rolled is transported from the R1 area to the R2 area in the roughing mill R1 area, the target width value W of the last pass of the second opposing rolls in the R2 area AIM is compensated to obtain the final width target value W of the last pass in the R2 area of the roughing mill R2 NEW ; The compensation process is as follows: Add the target width compensation value A of the last pass in the roughing mill R2 area to the target width value W of the second opposing roll set in step 1 AIM to obtain the final width target value W of the last pass in the roughing mill R2 area NEW ; After the compensation is completed, the target width value of the last pass of the second opposing roll in the roughing mill R2 area is set according to the W NEW and then the special-shaped billet of the steel slab is rolled according to the W NEW ​ 2. The automatic control method for the outlet width of a hot rolling roughing mill according to claim 1, characterized in that: When the target width compensation value A for the last pass in the R2 area of the roughing mill in Step 3 is greater than the target width correction value B for the last pass in the R2 area of the roughing mill, adjust the target width compensation value A for the last pass in the R2 area of the roughing mill to the target width correction value B for the last pass in the R2 area of the roughing mill. The target width correction value B for the last pass in the R2 area of the roughing mill is an empirical value, and the value range is an integer between 0 mm and 8 mm.

Images