JPH1110441A - Cutting method for long material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable cutting with the optimum yield by determining the combination of plural long materials to be continuously arranged and cut at the same time in such a manner as to minimize the total of cut-off amounts of all long materials of a suitably set long material group and a second long material group arranged immediately after the above group. SOLUTION: In cutting two groups in which the next group is added to each one group of combination of raw materials to be cut, by using the order of arranging rolled long materials and the stretching length thereof, a cutting pattern and combination are calculated to minimize the cut-off amount, and sequentially the group is determined one by one from the beginning of the rolling order. At the time of determining the second group, the result of calculation on the second group at the time of determining the first group is disregarded, and independently the calculation is performed to minimize the cut-off amounts of the second group with the third group. Thus, it is possible to carry out the calculation for a cutting method which is on-line, has small load and has the optimum yield.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cutting a long material, and particularly to a method for cutting a plurality of long materials after rolling, which is suitable for use in the production of a strip. The present invention relates to a method for cutting a long material that can be cut.

[0002]

2. Description of the Related Art In general, for an order in which a long material, particularly a straight bar which is a kind of a strip material, can be collected in a short length, when cutting the material after rolling, the material is first cut to an order length, and finally, Further, only when the short strip can be cut and collected, the short strip is collected. However, according to this method, all the remaining cuts less than the short strip length are discarded, resulting in a large loss.

In order to solve such a problem, Japanese Patent Laid-Open Publication No.
In 1-65714, for a predetermined number of strip materials in which a long material divided into a fixed size by a flying shear and a short material less than the fixed size are mixed, products of a predetermined order are cropped from the long material. A cutting pattern that can be cut with less loss is created as a primary cutting mode of the strip material group, and in the primary cutting mode, for a short material having a crop loss of an allowable value or more,
The first half has a length that is completely cut in the first half of the primary cutting mode, and a length that can be placed on a lifter that individually lifts each strip from a roller, and the order-receiving product Is virtually divided into a second half having a length that can be cut so that the crop loss is equal to or less than the allowable value, and the cutting pattern of the second half is set to the secondary cutting mode of each short material, and then the feed table is set according to the primary cutting mode. All the above group of strips are cut by a sizing machine and a cold shear. When a specific short material in the group of strips reaches a change point from the primary cutting mode to the secondary cutting mode, the entire group of strips is once lifted. Back up, lift the specific short material with a lifter, cut other strips according to the primary cutting mode,
Lifting, cutting is repeated to end the primary cutting mode, and then, of the short material being lifted by the lifter,
When the cutting pattern having the common cutting pattern in the secondary cutting mode is lowered onto the feed table and cut in accordance with the secondary cutting mode, and when the cutting pattern reaches a different point, the sheet is fed back to the lifter and lifted, and again on the lifter. It has been proposed that, among the short materials, a material having a common cutting pattern is lowered, and thereafter, the operations of cutting, reverse feeding, lifting and lowering are repeated to end the secondary cutting mode.

[0004]

However, in this method, it is necessary to change the cutting pattern (mechanical sorting) in the course of cutting, and it is necessary to remodel the equipment so that it can be sent back. In addition to the cost, the initial cutting group is fixed, so that the yield improvement rate cannot be improved much.

The present invention has been made to solve the above-mentioned conventional problems, and does not require special equipment.
An object of the present invention is to perform cutting with optimum yield.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a method of cutting a plurality of long materials after rolling, the method of cutting the long materials after rolling and the order of arrangement. The length of the first long material group appropriately set in consideration of the length of the long product and the total amount of the cutouts of all the long materials disposed immediately after the first long material group are minimized. In order to solve the above-described problem, a combination of a plurality of long members that are continuously arranged and cut at the same time is determined, and the process of cutting the determined first long member group is sequentially repeated. is there.

In the present invention, not the whole rolling lot but the combination (referred to as a flow) of the raw material when cutting is performed.
In each of the two sets, the next set is added to the two sets of cuts, and the arrangement order and the total length of the rolled long material, preferably the information (rolling order and weight) of the material after the heating furnace is inserted, are used. Using the arrangement order and the total length of the long material to be rolled, the cutting pattern and the combination that minimize the amount of cut-off are calculated, and one set is sequentially determined from the beginning of the rolling order. When deciding the second set, the result calculated for the second set when deciding the first set is ignored, and the calculation for independently truncating the two sets including the third set is performed independently. In this way, it is possible to calculate a cutting method that achieves an optimum yield with a small load online.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the following, with respect to a strip, particularly a straight
Embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a procedure for determining a cutting pattern according to the present embodiment. In the present embodiment, first, step 1
At 00, an initial value is set. Specifically, the rolling size,
Input the calculation prerequisite values such as the maximum number of simultaneous cuts, the minimum value thereof, the allowable ratio of short length mixing, the range of usable short length, and reset various counter values.

Next, in step 102, billet loading information such as billet loading order and billet weight is input.

Next, in step 104, the total length (referred to as az-roll length) of the strip rolled from one billet is calculated according to, for example, the following equation.

Azroll length = (actual weight of billet / single weight of billet) × (cross-sectional area of billet / cross-sectional area of product) (1)

Here, the actual billet weight is the actual weight of the billet, and the single billet weight is the weight per unit length of the billet.

Next, the process proceeds to step 106, and even if the charging of one lot has been completed or the charging of one lot has not been completed, the calculation is performed because the number of furnaces has reached a judgment value (for example, 60) or more. It is determined whether or not to start. here,
Waiting for the start of calculation until the completion of charging one lot or the number in the furnace becomes equal to or greater than the judgment value is because the short length used for each lot is determined and used. It is to determine from. In addition, even if the charging of one lot is not completed, the calculation is started when the number in the furnace becomes equal to or more than the judgment value because the calculation must be completed before the rolling is started. This is because shearing at a certain temperature or higher to prevent shear cracking becomes impossible.

Next, the routine proceeds to step 108, where the used short length is determined. The short length to be used is the shortest length that gives the best yield when each billet is sheared alone, when calculating the azroll length, and the shortest length that is optimal for the most billets in the calculation range is determined. use. Even when the lot has not been completely charged at the start of the calculation, the lot is determined based on the information up to that point, and the already-determined short length is used as it is for the parts charged after that point.

Next, the calculation of the cutting method is started in order from the first flow. The n-th flow will be described. In step 110, the optimum cutting is performed for the n-th flow when the number of simultaneous cuts is the maximum number of simultaneous cutting bodies. The pattern and the scrap length k (n) at that time are calculated. Next, the process proceeds to step 112, where, for the next (n + 1) th flow, the optimum cutting pattern when the number of simultaneous cuts is the maximum number of simultaneous cutting bodies and the scrap length k (n + 1) at that time are calculated. Then step 11
The process proceeds to step 4, and the calculation in step 112 is repeatedly changed from the maximum value of the number of simultaneous cuts minus one to the minimum value one by one sequentially.

At the time when the repetitive calculation for the (n + 1) -th flow in which the number of simultaneous cuts is changed is completed, step 11
Going to 6, the number of simultaneous cuts of the n-th flow is reduced by one, the (n + 1) -th flow is reconfigured, and the (n + 1) -th flow is sequentially changed from the maximum number of simultaneous cuts to the minimum value, and repeated. calculate.

After iteratively calculating all of the settable simultaneous cutting numbers, in step 118, the n-th flow cutting pattern is determined.

At this time, in order that the cutting efficiency is much lower than the rolling efficiency and the rolling is not hindered, the cutting is performed in a range where the sum of the number of the previous flow is equal to or more than the maximum simultaneous number + minimum value. The pattern and the chip length are calculated, and the combination of the number of streams and the cutting pattern with the smallest average chip length is adopted.

Next, the routine proceeds to step 120, where it is determined that the processing is completed. Specifically, count the number of billets,
If the number of the lot is exhausted, it is determined that the lot is finished. If the calculation is started before the completion of loading one lot, once the difference between the number of completed loadings and the number of completed calculations becomes less than twice the maximum number of simultaneous cuts, for example, The calculation can be stopped, and the calculation can be restarted when the lot charging is completed or when the number of uncalculated pieces again becomes equal to or larger than the calculation start determination value. In this case, the short length used is the one already determined for the lot.

If it is determined in step 120 that the calculation has not been completed, the process proceeds to step 122 and returns to step 110 to calculate the next flow.

In this way, the material information at the time of inserting the heating furnace is taken in, the calculation is started with all the lots loaded or a predetermined value, for example, 60 pieces are charged, and the calculation is divided by one set to be cut. In addition, the present invention can be carried out on an online computer terminal, and the yield of straight bars can be improved.

[0023]

Example: From a billet having a diameter of 60φ and about 2 tons, a standard length of 6 m and a short length of 4.5 to 5.5 m (calculation uses 4.5 m which gives the best yield when each billet is sheared alone). Short mixing ratio 10% or less, maximum number of simultaneous cuts 5
In the case of the number of pieces and the minimum value of one, the conventional example cuts at the maximum value of the number of simultaneous cuts (5 pieces), and the present invention changes the number of simultaneous cuts while changing the number of simultaneous cuts. FIG. 2 shows a case where a combination of the number of flows and the cutting pattern with a small average chip length is adopted.

In the conventional example, a cutting pattern of cutting a 6 m fixed length 16 times to a flow number consisting of billet numbers 1 to 5 and then cutting a 4.5 m short length once is used, and the average waste length is 2.9 m. For a flow number composed of five billets of billet numbers 6 to 10, a fixed length of 6 m is set to 1
In a cutting pattern in which a short strip of 4.5 m was cut three times, the average debris length was 2.0 m, whereas according to the embodiment of the present invention, the flow numbers were billet numbers 1 to 4. The cutting pattern is 15 fixed lengths, 3 short lengths, the average chip length is 1.4 m, and the flow numbers are billet numbers 5 to 7.
The cutting pattern is composed of 15 regular lengths, one short length, and one regular length, the average scrap length is 1.3 m, the flow number is composed of billet numbers 8 to 9, and the cutting pattern is a regular length. 1
Seven times, and the average scrap length was 1.6 m.

In summary, in the conventional example, the average waste length was 2.45 m (the back yield was 2.45%). In the embodiment of the present invention, the average waste length was 1.43 m. (Table yield: 1.43%), and it was confirmed that the yield was improved by 1.02%.

It should be noted that the cutting pattern is merely the content of the cutting operation. In the case of a short billet, the billet is lost in the middle of the pattern, and the surplus length becomes waste. Also in the calculation examples, the calculation of the number of pieces and the calculation of the yield require the number of products and the length of chips that can be accurately collected.

In the above calculation example, the short length is set to 4.5.
Although m is fixed, according to the present invention, the most advantageous short length can be used for the whole lot, and the yield is further improved.

According to the present invention, since the number of simultaneous cuts is increased or decreased, the possibility of a combination that would be disadvantageous if cut at the same time can be reduced. In addition, to the limit of the short mixing rate allowable value, it is possible to collect short strips, etc.,
The yield can be improved.

In the above description, an example in which the present invention is applied to the cutting of a straight bar, and the length and arrangement order of the straight bar after rolling are determined from the weight of the billet at the time of charging the heating furnace and the order of the furnace. However, the application of the present invention is not limited to this,
It is apparent that the present invention can be similarly applied to cutting of a general strip material and further a long material, and that the length and arrangement order after rolling may be measured after rolling.

[0030]

According to the present invention, the present invention can be implemented only with existing equipment, and no capital investment is required. Also, since calculation is performed for each group of strips in the rolling order, the range of simultaneous calculation is small, the calculation load on the computer is reduced, and calculation can be performed without being restricted by the insertion pitch or the size of the lot. It is also possible to divide the calculation. Furthermore, the optimization for the efficiency and the shortage mixing rate, etc., and the effect on the yield are optimized not only for one set of material to be cut but also for the next set, taking into account the next set. Yield improvement comparable to that is possible, and leveling of the cutting capability is also possible at a high level. In particular, when the material information after the heating furnace is charged is used, accurate calculations can be easily performed, and there are excellent effects such as small variations.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a calculation procedure in an embodiment of the present invention.

FIG. 2 is a diagram showing a comparison between calculation results of a conventional example and an example of the present invention.

Claims (2)

[Claims] 1. A method of cutting a plurality of long materials after rolling, wherein a method for cutting a plurality of long materials at the same time is required. Then, the first long material group appropriately set and the second long material group disposed immediately after the first long material group are continuously arranged and simultaneously arranged so that the total of the cut-off amounts of all the long materials is minimized. A method for cutting a long material, comprising: determining a combination of a plurality of long materials to be cut; and sequentially repeating a process of cutting the determined first long material group. 2. The method according to claim 1, wherein said elongated material is a strip, and the length and arrangement of the strip after rolling are determined from the weight of the material when the heating furnace is inserted and the order of entering the furnace. Characteristic long material cutting method.