阅读说明：本技术 平整机过焊缝的控制方法 (Control method for passing welding seam of temper mill ) 是由 黄才铨 张洁露 于 2018-09-13 设计创作，主要内容包括：本发明提供了一种平整机过焊缝的控制方法,采用增大弯辊力到大于轧制力的方式,使平整机下工作辊自动下降,从而打开用于带钢焊缝通过平整机的辊缝,包括如下步骤：步骤1：机组降速到过焊缝速度；步骤2：轧制力下降到过焊缝轧制力的设定值；步骤3：弯辊力上升到过焊缝弯辊力的设定值；步骤4：焊缝通过平整机后,轧制力和弯辊力重新回到初始轧制时的设定值,随后机组升速到初始工作速度；本发明对轧制力和弯辊力变化的时间点有精确计算。本发明通过优化过焊缝模式,已最简洁的步骤过焊缝,减少带钢过焊缝废料长度,提高带钢的成材率。(The invention provides a method for controlling the passing of a welding seam of a temper mill, which adopts a mode of increasing a roll bending force to be larger than a rolling force to automatically lower a working roll under the temper mill so as to open a roll seam for a strip steel welding seam to pass through the temper mill, and comprises the following steps: step 1: the speed of the machine set is reduced to the speed of passing the welding seam; step 2: the rolling force is reduced to a set value of the over-welding seam rolling force; and step 3: the roll bending force rises to the set value of the roll bending force of the over-welding seam; and 4, step 4: after the welding seam passes through the planisher, the rolling force and the roller bending force return to the set values in the initial rolling process again, and then the unit is accelerated to the initial working speed; the invention has accurate calculation to the time point of the change of the rolling force and the roll bending force. According to the invention, the welding seam is passed through the simplest steps by optimizing the welding seam passing mode, the length of the waste materials of the strip steel welding seam is reduced, and the yield of the strip steel is improved.)

1. A method for controlling the welding seam passing of a temper mill is characterized in that a mode of increasing a roll bending force to be larger than a rolling force is adopted, so that a lower working roll of the temper mill automatically descends, and a roll seam for a strip steel welding seam to pass through the temper mill is opened, and comprises the following steps:

step 1: the speed of the machine set is reduced to the speed of passing the welding seam;

step 2: the rolling force is reduced to a set value of the over-welding seam rolling force;

and step 3: the roll bending force rises to the set value of the roll bending force of the over-welding seam;

and 4, step 4: after the welding seam passes through the planisher, the rolling force and the roll bending force return to the set values in the initial rolling process again, and then the unit is accelerated to the initial working speed.

2. The control method for the bead passing of the temper mill according to claim 1, wherein the time node of the reduction of the rolling force in the step 2 is calculated by the following method:

wherein D is_RFIndicating the distance of the weld to the temper mill, RF, when the rolling force begins to drop_ActRepresenting the actual value of the rolling force during initial rolling, RF_SetSet point for roll force, RF, at passing weld_RampShows the falling gradient of the rolling force, D₁And when the rolling force is reduced to a set value when the rolling force passes through the welding line, the distance from the welding line to the temper mill is shown, and v shows the speed of the unit passing through the welding line.

3. The method of claim 1, wherein the time node of the roll bending force rise in step 3 is calculated by:

wherein D is_BendIndicating the distance, Bend, of the weld to the temper mill when the roll bending force begins to rise_ActIndicating the actual value of the roll bending force at the initial rolling, Bend_SetIndicating the set value of the roll bending force during the passing of the weld bead, Bend_RampShows the slope of the rise of the roll bending force, D₂And when the bending roll force rises to a set value when the bending roll force passes through the welding line, the distance from the welding line to the temper mill is shown, and v shows the speed of the unit passing through the welding line.

Technical Field

The invention relates to the field of metallurgy automation, in particular to a control method for a welding line passing of a temper mill.

Background

The process flow before and after the cold acid temper mill is shown in figure 1, the strip steel enters the temper mill after passing through 1 four-roller tension roller, and finally enters 1 two-roller tension roller to leave the temper mill. Tension meters are arranged at the front and the rear of the temper mill to measure the front and rear tension. The leveler mechanism is mainly composed of 2 work rolls, 2 push-up cylinders and a roll bending cylinder, as shown in fig. 3. Because the welding seam of the directly pressed strip steel can damage the roller, when the welding seam passes through the flattening machine, the roller must open a certain roller seam, and the roller seam is closed after the welding seam passes through, and the mode is called as micro-open welding seam.

When a traditional planishing mill slightly passes through a welding seam, the speed of a unit needs to be reduced to 30m/min, the rolling force is reduced to 50 tons, the control is switched to position control through the rolling force, the roller seam is opened by 5mm, after the welding seam passes through the planishing mill by 1m, the planishing mill is closed, and the speed of the unit is increased after the rolling force reaches an initial working set value, as shown in figure 3, the unit is subjected to the switching process between two tension mode control modes, a rolling force mode and a roller seam control mode. The process is long and the distance of the over-welding seam is also long. The yield of the strip steel is influenced, certain welding seam waste is generated, and the production rhythm of the unit is influenced (the furnace section needs to run at a reduced speed at a high speed).

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a control method for the over-welding seam of a temper mill.

According to the control method for the welding seam passing of the temper mill, provided by the invention, the lower working roll of the temper mill is automatically lowered by increasing the roll bending force to be greater than the rolling force, so that the roll seam for the welding seam of the strip steel to pass through the temper mill is opened, and the method comprises the following steps:

step 1: the speed of the machine set is reduced to the speed of passing the welding seam;

step 2: the rolling force is reduced to a set value of the over-welding seam rolling force;

and step 3: the roll bending force rises to the set value of the roll bending force of the over-welding seam;

and 4, step 4: after the welding seam passes through the planisher, the rolling force and the roll bending force return to the set values in the initial rolling process again, and then the unit is accelerated to the initial working speed.

Preferably, the time node of the reduction of the rolling force in step 2 is calculated by the following method:

wherein D is_RFIndicating the distance of the weld to the temper mill, RF, when the rolling force begins to drop_ActRepresenting the actual value of the rolling force during initial rolling, RF_SetIndicating rolling while passing the weldSet value of braking force, RF_RampShows the falling gradient of the rolling force, D₁And when the rolling force is reduced to a set value when the rolling force passes through the welding line, the distance from the welding line to the temper mill is shown, and v shows the speed of the unit passing through the welding line.

Preferably, the time node of the roll bending force rising in step 3 is calculated by the following method:

wherein D is_BendIndicating the distance, Bend, of the weld to the temper mill when the roll bending force begins to rise_ActIndicating the actual value of the roll bending force at the initial rolling, Bend_SetIndicating the set value of the roll bending force during the passing of the weld bead, Bend_RampShows the slope of the rise of the roll bending force, D₂And when the bending roll force rises to a set value when the bending roll force passes through the welding line, the distance from the welding line to the temper mill is shown, and v shows the speed of the unit passing through the welding line.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention simplifies the flow of micro-opening over-welding seams of the temper mill and improves the production rhythm.

2. The method effectively reduces the length of the strip steel waste in the over-welding seam of the temper mill by optimizing the over-welding seam mode of the temper mill, and improves the yield of the strip steel.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a flow chart of a leveler process.

FIG. 2 is the change of the speed, the rolling force and the roll gap of the traditional planisher along with the time in the process of passing the weld joint.

Fig. 3 is a schematic view of the structure of the leveler.

FIG. 4 is a graph of the change in the speed, rolling force, roll bending force of the machine over time during the weld pass of the present invention.

Fig. 5 is a flowchart illustrating steps of a control method according to the present invention.

The SPM in fig. 1 indicates a roller, and TM1 and TM2 indicate a first push-up cylinder and a second push-up cylinder, respectively.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

The leveler has a structural principle as shown in fig. 2, in which the resultant of the positive and negative bending forces is referred to as a bending force. The lower working roll is under the combined action of the bending roll force and the rolling force of the pushing cylinder. When the roll bending force is larger than the rolling force, the lower working roll is spread, and the purpose of slightly opening the roll gap is achieved.

According to the control method for the welding seam passing of the temper mill, provided by the invention, the flow of the micro-opening welding seam passing of the temper mill is simplified, and the lower working roll of the temper mill is automatically lowered by increasing the roll bending force to be greater than the rolling force, so that the roll seam for the welding seam of the strip steel passing through the temper mill is opened, and the method comprises the following steps:

step 1: the speed of the machine set is reduced to the speed of passing the welding seam;

step 2: the rolling force is reduced to a set value of the over-welding seam rolling force;

and step 3: the roll bending force rises to the set value of the roll bending force of the over-welding seam;

and 4, step 4: after the welding seam passes through the planisher, the rolling force and the roll bending force return to the set values in the initial rolling process again, and then the unit is accelerated to the initial working speed.

Preferably, the time node of the reduction of the rolling force in step 2 is calculated by the following method:

wherein D is_RFIndicating the distance of the weld to the temper mill, RF, when the rolling force begins to drop_ActIndicates the beginningActual value of rolling force at start of rolling, RF_SetSet point for roll force, RF, at passing weld_RampShows the falling gradient of the rolling force, D₁And when the rolling force is reduced to a set value when the rolling force passes through the welding line, the distance from the welding line to the temper mill is shown, and v shows the speed of the unit passing through the welding line.

Preferably, the time node of the roll bending force rising in step 3 is calculated by the following method:

wherein D is_BendIndicating the distance, Bend, of the weld to the temper mill when the roll bending force begins to rise_ActIndicating the actual value of the roll bending force at the initial rolling, Bend_SetIndicating the set value of the roll bending force during the passing of the weld bead, Bend_RampShows the slope of the rise of the roll bending force, D₂And when the bending roll force rises to a set value when the bending roll force passes through the welding line, the distance from the welding line to the temper mill is shown, and v shows the speed of the unit passing through the welding line.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.