阅读说明：本技术 一种连铸机在中包快换期间扇形段自动躲接痕板坯的方法 (Method for automatically hiding joint mark slabs in sector section during quick change of tundish of continuous casting machine ) 是由 富君普 孟庆辉 安晓东 李由 鮑振东 张同宇 马铁刚 于 2019-09-20 设计创作，主要内容包括：本发明公开一种连铸机在中包快换期间扇形段自动躲接痕板坯的方法,快换期间扇形段内的接痕板坯,在快换结束铸机起步后,采集现场信号监控接痕板坯在扇形段内实际位置,当该段板坯进入对应扇形段时,所述扇形段按预先设定的目标位置抬起1-5mm,达到增大扇形段辊缝减小扇形段框架对板坯夹持力的目的,当这段接痕板坯拉出对应扇形段时,这个扇形段再压回正常浇铸位置。本发明通过增大扇形段辊缝减小扇形段框架对板坯夹持力的目的,用以降低拉矫力矩解决铸机拉不动板坯的问题,同时使扇形段免受过大力冲击,延长扇形段在线使用寿命,降低设备维护成本。(the invention discloses a method for automatically hiding a mark-connecting plate blank in a fan-shaped section during quick change of a continuous casting machine in a tundish, wherein the mark-connecting plate blank in the fan-shaped section during the quick change is collected with a field signal after the casting machine is started after the quick change is finished, the actual position of the mark-connecting plate blank in the fan-shaped section is monitored, when the plate blank enters the corresponding fan-shaped section, the fan-shaped section is lifted by 1-5mm according to a preset target position, so that the purpose of increasing the roll gap of the fan-shaped section and reducing the clamping force of a frame of the fan-shaped section on the plate blank is achieved, and when the mark-connecting plate blank is pulled out of the corresponding fan-shaped. The invention aims to reduce the clamping force of the fan-shaped section frame on the plate blank by increasing the roll gap of the fan-shaped section, so as to reduce the straightening torque, solve the problem that the plate blank is not pulled by a casting machine, simultaneously prevent the fan-shaped section from being impacted by overlarge force, prolong the on-line service life of the fan-shaped section and reduce the maintenance cost of equipment.)

1. A method for automatically hiding a slab with a joint mark in a sector section during quick change of a tundish of a continuous casting machine is characterized by comprising the following steps: and (3) collecting field signals to monitor the actual position of the mark-connecting plate blank in the fan-shaped section after the casting machine is started after the quick change is finished, lifting the fan-shaped section by 1-5mm according to a preset target position when the plate blank enters the corresponding fan-shaped section, so as to achieve the purpose of increasing the roll gap of the fan-shaped section and reducing the clamping force of a frame of the fan-shaped section on the plate blank, and pressing the fan-shaped section back to the normal casting position when the mark-connecting plate blank is pulled out of the corresponding fan-shaped section.

2. method for the automatic lane-hiding slab of a sector during quick change of a tundish according to claim 1, characterized in that: the sector section is from the inlet of the 3 sections to the outlet of the crystallizer.

3. method for the automatic lane-hiding slab of a sector during quick change of a tundish according to claim 1, characterized in that: the casting machine control program is modified, operation by production personnel is avoided, human errors are reduced, starting signals of quick-change joint mark hiding plate blanks are automatically recognized through the exchange positions of two tundish carriages during quick change of the casting machine, the plate blank pull-out position real-time calculation is carried out by utilizing the S7 control program and a withdrawal straightening machine encoder, compared with the actual mechanical length of a fan-shaped section, the opening and pressing signal output of the corresponding fan-shaped section is calculated and controlled, finally the slightly thick joint mark plate blank is pulled out of the fan-shaped section and is prevented from being extruded by overlarge clamping force of the fan-shaped section, the moment of the withdrawal straightening machine is reduced, the condition that the casting machine does not pull out a blank is avoided, and the function of hiding the plate blank is automatically cancelled once the plate blank is.

4. Method for the automatic lane-hiding slab of a sector during quick change of a tundish according to claim 1, characterized in that:

The length of the mark-connecting plate blank is defined as that when the quick-change casting flow of the tundish stops, the section of plate blank with 0.5 m of new molten steel is pulled out from the outlet of the No. 2 fan-shaped section to the crystallizer, and the section of the mark-connecting plate blank is sequentially lifted when passing through the corresponding fan-shaped section; after the quick change automatic starting condition of the tundish is met, after quick change starting, normal fluctuation of the liquid level due to opening of the fan-shaped section is avoided, the fan-shaped section automatically avoids the action of jointing plate blanks under the liquid level, and after the program is set for 3-4 minutes, the plate blanks are pulled out by more than 3 meters to carry out opening and closing actions of the fan-shaped section according to a preset value; when the opening length of the activated sector reaches the quick-change opening tracking value of the corresponding sector, the sector is automatically opened to a quick-change target position of the system; when the closing length of the activated sector reaches the quick-change closing tracking value of the corresponding sector, the sector is automatically closed to a system target position; and the target position of the sector system is determined by the current casting machine soft reduction mode.

Technical Field

The invention relates to the technical field of metallurgy, in particular to a processing method of a plate blank.

Background

Since the advent of continuous casting machines, continuous casting machines have been rapidly developed because of the fact that, compared with the conventional "die casting" process, the process for producing steel billets is greatly simplified, a large amount of energy is saved, steel billets can be continuously cast on one machine set, the metal yield and the yield can be improved, and the cost can be reduced.

Because the quick change of the tundish can be realized in the production of the continuous casting machine, the number of continuous casting furnaces is greatly increased in one casting period, the continuous production of more furnaces is realized, the labor condition of workers is fundamentally changed, and the productivity is correspondingly improved. However, during the quick change of the continuous casting machine in the tundish, the pulling speed of the continuous casting machine is reduced to 0 speed for about 4-5 minutes, the temperature of the plate blank in the fan-shaped section is reduced, the plate blank is hardened, after the casting machine starts again after the new molten steel forms a complete joint mark in the crystallizer, the newly cast plate blank is slowly pulled out through the fan-shaped section of the casting machine, in the process, the joint mark plate blank needs to pass through the fan-shaped sections with different opening degrees and contraction rod joints, the contraction quantity of the rod joints of each fan-shaped section is 0.3-2mm, so that the clamping and extrusion of the fan-shaped sections on the joint mark plate blank are increased, the temperature of the plate blank is higher during normal production, the pulling resistance of the plate blank is small, when the tundish is changed quickly, the temperature of the plate blank is lower, the pulling resistance of the plate blank is large, the original technology adopts a force limiting technology to solve after the situation occurs, and the force limiting means that when, the segment can automatically adjust the rod gap to reduce the clamping force of the segment so as to reduce the resistance of blank drawing, and the method has limited adjustment and can not meet the production requirement.

Through production experience of many years, during the quick change of a tundish of a casting machine, the condition of pulling a fixed blank often occurs, most of the fixed blank is between 13 meters and 18 meters of a newly pulled plate blank and corresponds to 4 sections and 8 sections of a fan-shaped section, wherein 7 sections to 8 sections are straightening sections, and the normal plate blank pulling and straightening moment is about 40 percent. During the quick change, the temperature of the slab is reduced because the mark-connecting slab stays for about 4-5 minutes at a speed of 0 in the fan-shaped section, and the mark-connecting slab about 1 meter after the quick change is over hard, and the slab is thicker because the smallest stick seam of the 0-2 sections is larger than that of other sections (determined by the process size of equipment). After the quick change of the casting machine is started, the joint mark slab can be pulled out through the fan-shaped section by the factors, the pulling and straightening torque is greatly increased, and the torque is almost doubled by about 70-90%. Many years of production have seen the situation where the caster pulls the blank during a quick change. The device inspection, control program research and FDA data analysis are utilized to obtain that a slightly-thick seam welding plate blank with the thickness of about 8 meters (from a section 3 of an inlet to a crystallizer outlet) is arranged in a sector section during quick change, when the plate blank passes through each sector section under the driving of a withdrawal and straightening machine, in order to ensure that the actual position of the sector section is consistent with the target position, a sector section frame generates very large clamping force, once a force limiting protection value of the sector section is triggered, a rod seam can be automatically adjusted by the sector section, and the adjusted size is directly related to the force limiting protection value. The large protection value of force limitation is not obvious to the adjustment force action of the sector section during quick change of the tundish, and the small protection value of force limitation is obvious to the adjustment force action of the sector section during quick change of the tundish, but can influence the rod gap precision during normal production. The method has the advantages that the trace slab causes very large clamping force of the sector section frame during quick change, the load is increased for the withdrawal and straightening machine, the trace slab is the main reason that the casting machine cannot pull the slab during quick change of the tundish, and a solution needs to be found.

Disclosure of Invention

In order to solve the technical problem, the invention aims to provide a method for automatically hiding a slab with a sector section from a joint mark during quick change of a tundish of a continuous casting machine, which is characterized by comprising the following steps: and (3) collecting field signals to monitor the actual position of the mark-connecting plate blank in the fan-shaped section after the casting machine is started after the quick change is finished, lifting the fan-shaped section by 1-5mm according to a preset target position when the plate blank enters the corresponding fan-shaped section, so as to achieve the purpose of increasing the roll gap of the fan-shaped section and reducing the clamping force of a frame of the fan-shaped section on the plate blank, and pressing the fan-shaped section back to the normal casting position when the mark-connecting plate blank is pulled out of the corresponding fan-shaped section.

The sector section is from the inlet of the 3 sections to the outlet of the crystallizer.

The method is characterized in that a casting machine S7 control program is modified, operation of production personnel is not needed, human errors are reduced, starting signals of quick-change joint mark hiding slabs are automatically identified through the exchange positions of two tundish trucks during quick change of the casting machine, the control program of a continuous casting machine control system is completed by S7 software by utilizing S7 (the name of Siemens programming software is STEP7 abbreviation, and if the functions of a continuous casting machine are improved and optimized, the control program and a withdrawal straightening machine encoder need to be completed by S7 programming), slab pulling-out positions are calculated in real time, compared with the actual mechanical length of a fan-shaped section, the corresponding fan-shaped section is controlled to be opened and pressed, signals are output by calculation, and finally the slab with the slightly thick joint mark is pulled out of the fan-shaped section, so that the slab is prevented from being extruded by too large clamping force of the fan-shaped section, the moment of the withdrawal straightening machine is reduced, and the slab hiding function of the slab is automatically.

The length of the mark-connecting plate blank is defined as that when the quick-change casting flow of the tundish stops, the section of plate blank with 0.5 m of new molten steel is pulled out from the outlet of the No. 2 fan-shaped section to the crystallizer, and the section of the mark-connecting plate blank is sequentially lifted when passing through the corresponding fan-shaped section; after the quick change automatic starting condition of the tundish is met, after quick change starting, normal fluctuation of the liquid level due to opening of the fan-shaped section is avoided, the fan-shaped section automatically avoids the action of jointing plate blanks under the liquid level, and after the program is set for 3-4 minutes, the plate blanks are pulled out by more than 3 meters to carry out opening and closing actions of the fan-shaped section according to a preset value; when the opening length of the activated sector reaches the quick-change opening tracking value of the corresponding sector, the sector is automatically opened to a quick-change target position of the system; when the closing length of the activated sector reaches the quick-change closing tracking value of the corresponding sector, the sector is automatically closed to a system target position; and the target position of the sector system is determined by the current casting machine soft reduction mode.

Compared with the prior art, this patent can compensate because of the conticaster during well package quick change, the temperature decline of slab in fan-shaped section, and the slab hardens, connects the trace slab to pass through each fan-shaped section for fan-shaped section increases the centre gripping extrusion to the trace slab, causes the trace slab to be harder to lead to drawing motionless slab, and original "power is injectd" technical method and is adjusted limitedly, can not solve the problem completely after this condition takes place, has not satisfied the production requirement. Through system improvement, when the section of the mark-connecting plate slab enters the corresponding sector section, the sector section is slightly lifted by 1-5mm according to a preset target position, the purpose of increasing the roll gap of the sector section and reducing the clamping force of a frame of the sector section on the slab is achieved, the problem that the slab is not pulled by a casting machine is solved by reducing the straightening moment, meanwhile, the sector section is prevented from being impacted by excessive force, the on-line service life of the sector section is prolonged, the maintenance cost of equipment is reduced, and a positive effect is achieved.

Drawings

FIG. 1 is a cross-section of a corresponding view of a frame force and segment lifting during a segment joint trace hiding process;

FIG. 2 is a cross section of a corresponding diagram of a frame force with a joint mark hiding function and a frame force when an original fan-shaped section is not lifted;

FIG. 3 is a sector position sensor circuit diagram;

FIG. 4 is a sector servo valve circuit diagram.

Detailed Description

During the quick change, the mark-connecting plate blank with the length of about 8 meters (from the inlet of the section 3 to the outlet of the crystallizer) in the fan-shaped section is started, after the quick change is finished, the S7 control program and the position sensor are used for collecting field signals to monitor the actual position of the plate blank in the fan-shaped section, when the plate blank enters the corresponding fan-shaped section, the fan-shaped section is slightly lifted by 1-5mm according to the preset target position, the purpose of increasing the roll gap of the fan-shaped section and reducing the clamping force of the fan-shaped section frame on the plate blank is achieved, and when the thick mark-connecting plate blank is pulled out of the corresponding fan-shaped section, the fan-shaped section. Based on the principle, the control program of the casting machine S7 is modified, operation by production personnel is not needed, human errors are reduced, a starting signal of a quick-change trace-hiding slab is automatically identified through the exchange positions of two tundish carriages during quick change of the casting machine, the pulling-out position of the slab is calculated in real time by using the control program of S7 and a withdrawal straightening machine encoder, the actual mechanical length of the segment is compared with the actual mechanical length of the segment, the corresponding segment is controlled to be opened and output by calculation, finally the slab with the slightly thicker trace-hiding slab is pulled out of the segment, the slab is prevented from being extruded by the excessive clamping force of the segment, the moment of the withdrawal straightening machine is reduced, the situation that the slab is not pulled by the casting machine is avoided, and the function of hiding the trace slab is automatically cancelled. In order to prevent special conditions from occurring in the period, the control program introduces various signal chain protections to ensure the safe operation of the casting machine.

Welding mark hiding slab program calculation step

The continuous casting machine is composed of a plurality of fan-shaped sections, each fan-shaped section plays a role in supporting a slab, a cooling device is arranged on each fan-shaped section, the slab is properly cooled, and the slab is pulled out of the continuous casting machine, wherein the fan-shaped sections are numbered on the casting machine and are sequentially 1 section, 2 sections and the like from front to back; the length of the seam-welded slab is defined as that when the quick casting flow of the tundish stops, the section of the slab with 0.5 m is drawn out from the outlet of the No. 2 fan-shaped section to the new molten steel in the crystallizer, and is about 8227+ 500-8727 mm, and the section of the seam-welded slab keeps being lifted in sequence when passing through the corresponding fan-shaped section. And after the automatic starting condition of the quick change of the tundish is met, recording and storing the total pouring length A of the casting machine as the quick change point length B, and calculating the quick change new pouring length L (A-B) by a program. The new pouring length L +8727mm (2-segment outlet) is changed quickly to the activation segment opening length K. And (3) quickly changing the new pouring length L-500mm to the activating sector closing length G.

Quick-change opening and closing tracking value of corresponding sector section ((unit: millimeter)

After the quick-change starting, the normal fluctuation of the liquid level due to the opening of the fan-shaped section is avoided, the fan-shaped section automatically carries out the action of hiding the seam plate blank under the liquid level as far as possible, and after the program is set for about 3-4 minutes, the plate blank is pulled out for more than 3 meters to carry out the opening and closing actions of the fan-shaped section according to the preset value. And when the 'activation sector opening length K' reaches the corresponding sector quick-change opening tracking value, the sector can be automatically opened to the system quick-change target position. The segment roll slot opened to table 13/15 when in soft-reduction mode and 242.5mm when not in soft-reduction. When the 'activated segment closing length G' reaches the corresponding segment quick-change closing tracking value, the segment is automatically closed to the system target position. And the sector system target position is determined for the current casting machine soft reduction mode (LPC, pull rate, manual).