JPS6087962A - Cutting method of long sized billet - Google Patents

Abstract

PURPOSE:To cut a slab without demensional defect in the cut length by disposing laser detector carriages for deceleration and stoppage at a prescribed space for cutting distance on the downstream of a cutting torch carriage on a cutting line for a slab and detecting the overall length of the slab with the detecting carriage at the rear end on the upper stream. CONSTITUTION:A carriage 5 having a photodetector 7 for the irradiated laser light for deceleration and a photodetector 8 for the irradiated laser light for stoppage is disposed on the downstream of a cutting torch 3 carriage 4 on a cutting line rail 2 for a slab at a prescribed space for the cutting distance. The carriages 4, 5 are moved in parallel so as to match a laser photodetector 8 for stoppage with the actual stop position of a slab 5. The overall length of the slab is detected with the detector 9 for detecting the rear end of the slab on the upstream and the carriage 4 is moved to the position where there is no waste for cutting, by which the slab is cut. The above-mentioned operation is automatically controlled by a computer according to the set value, by which the defective cutting length is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is a method for performing secondary cutting on-line or off-line of a long steel piece such as a slab obtained by continuous casting and cutting into a certain length. This relates to the method of

(Prior Art) Continuously cast slabs are first cut into predetermined lengths using a gas canker or the like, and then cut into required lengths (secondary cutting) online or offline. In this case, the required slab length for steel production is determined based on the planned total length of the slab, and secondary cutting is performed from this length K. However, during the second cutting, there are many length measurement errors when cutting at a constant height, so the accuracy of the overall slab length is low. ), the yield is poor.

In addition, in the past, when measuring the length of a slab, a 411J long roll was used that was in contact with the slab, but this method was prone to measurement errors due to slippage, etc., and this made it difficult to achieve accurate cutting work. was inhibiting.

(Object of the invention) 6FllllL+r/))F'*'I'l-2B? sivtm-y=-y++++bpy-J-, w, +
-ML7, 7.1- The object of the present invention is to provide a cutting method with a high degree of precision and a good yield. Another object of the present invention is to provide a cutting method that allows cutting to be maintained at approximately the same position at all times, without damaging the conveying rollers, and which facilitates the disposal of cutting slag.

(1η composition of the invention) The cutting method for achieving the above object is to use a LIJ shearing truck equipped with a cutting torch on the cutting and conveying line of the steel billet, and a 27-J Laser light irradiation/
A steel billet tip detection cart with light receivers arranged side by side and a steel billet rear end detection cart are arranged, and AiJ 1) J cutting cart and tip detection cart are positioned at a distance ν111 corresponding to the planned cutting length. , ``The incoming steel J'l is detected by the laser beam irradiation/receiver in 27.1, and is decelerated and stopped, and the tip detection cart and cutting cart, which are out of position when stopping the steel piece due to inertia, are moved. Then, the rear end of the steel billet is detected by a rear end detection cart, the length of the steel billet is actually measured, and this is compared with the planned total length, and the cutting position is changed based on the difference and the cut is made. .

The details of the failure will be explained below based on the drawings.

FIG. 1 shows a steel billet cutting and conveying line for carrying out the present invention, in which rails 2 are laid on both sides of a roller table 1 that conveys a steel billet (slab) S to be cut. On top of 2 are mounted three carts, a cutting cart 4 carrying IFII cutting 1 and 3, a billet tip detection cart 5, and a billet detection rear end cart 6, which are movable. There is. These carts are all made of steel J! It is formed into a portal shape so that it can pass through (Figure 2).

The cutting cart 4 is equipped with a commonly used gas cutting mechanism, and the cutting torches 3 are comprised of one-piece torches that move toward and away from each other. In addition, the tip detection stand jlT5
Two pairs of detectors using laser beams are installed so as to face each other in the width direction of the steel strip. One of the detectors is for decelerating the steel billet S being conveyed, and is composed of a laser beam irradiator 7a and a light receiver 7b, and the other detector is installed in parallel on the downstream side in the traveling direction of the billet from the deceleration detector. It is for stopping the billet.

It also consists of a Rayleigh light irradiator 8a and a light receiver 8b. Furthermore, the following 1. The i-detection cart 6 is also provided with a pair of laser beam irradiator 9a and light receiver 9b.

In addition, in the present invention, a detector using laser light is used because it can detect the target object with higher precision than other methods, and allows for minute placement 11. .

Next, the cutting operation of the present invention will be explained.

As shown in FIG. 3(a), the cutting cart 4 is stopped at a predetermined cutting position (preferably between adjacent rollers so as not to damage one of the rollers during cutting), and then stopped at the origin ( A1. ;Move the detection cart 5 (hereinafter referred to as the first cart for convenience) to the right in the figure, and the distance ν111 between the cutting torch 3 and the stop detector 8 becomes the planned cutting length 1.
-Stop at the position where it becomes o. In this state, the steel piece S may be on the right side.
When the tip of the steel billet is detected by the deceleration detector 7 as shown in Figure 3 (B), a deceleration command is immediately issued to the drive section of the conveying roller, and the tip stops at θ ( When detected by the detector 8, the drive of the conveying rollers immediately stops.

However, as shown in Fig. 3 (-C), even though the conveyance rollers have stopped, inertia acts on the steel piece S, which is the M feature, and the tip of the steel piece is at a position beyond the stop detector 8. (This overdistance is set as Δl).This positional deviation is shown in Figure 3. At this time, the moving distance of the first cart 5 is measured and the length Δl is measured.

At the same time, the rear end detection cart 6 (hereinafter referred to as the second cart)
is moved to the left and the rear end of the steel slab is detected. At this time, too, the amount of movement of the second truck 6 is measured. In actual operation, the first stop position of the new truck 4 and the 1. The origin positions of the second carts 5 and 6 are input into the arithmetic control unit (for example, a computer) K, and ■, 0. If the actually measured Δl and the amount of movement of the second trolley 6 are manually calculated each time, the total length of the steel piece S to be cut will be the same as that of the second trolley.11.
! At point j, the real value is inf.

The actual measured value of the total length of the steel billet S is input to the control unit and compared with the planned total length of the steel billet that has been manually inputted in advance, and if there is no difference between the two, the cutting operation is started at the same cutting position (of course [ i1J Dandaitun moves to the left by 21 minutes and cuts at the length of Lo). If there is a difference between the two values, it's true! Change the cutting position to correct the dimensions according to the total length. In Figure 2 (E), Δe + α (α is the correction) cutting u
A state in which the car 4 is moved and cutting is performed is shown. For example, if the planned total length is 10,771 mm and you are trying to measure it into two pieces of steel measuring 6 m and 4 m, the actual total length is 9.
If it was 5 m, another dimension, for example 5.5
It can be modified to cut into 4 m and 4 m. In the past, I used to prepare a large number of measurements of steel billets according to orders in advance, and put them into the computer computer, and if the actual total length was different from the planned total length, I would be able to find the exact length that matched the actual length. It is sufficient to be able to change the dimensions to something similar to this.

Note that before the cutting operation by the cutting torch 3 is started,
The first and second a cars 5 and 6 are kept at the rear of the original position.

When cutting is completed, the roller table is driven to move the cut steel piece and prepare for cutting the next steel piece.

(Fourth Effect of the Invention) What are the following effects of the cutting method of the present invention? 4? It leaks.

(1) Measure the total length of the incoming steel billet with high accuracy < 1llll
In addition to this, the steel pieces can be cut to the optimum dimensions for hunting based on this measured length value, resulting in a significant reduction in cropping and a significant improvement in yield. For example, in actual operation, it was confirmed that the yield rate for buried plate orders exceeded the previous limit of 96%.

(2) The steel billet can be easily stopped by driving the roller table (stopping and stopping), and its movement by iRl'l2 can also be carried out with axle load at each station.

(:(+) Since it is possible to cut the steel piece into a specific narrow range, the cutting position can be limited to within the interval between the conveyor rollers, and damage can be caused without lowering the rollers. No need for cutting slag treatment or dust collection.

Soundproofing measures become easy.

[Brief explanation of drawings]

Figure 1 shows the overall settings 1 for implementing the cutting method of the present invention.
FIG. 2 is a sectional view taken along the line A-A' in FIG. 1, and FIGS. S... Steel piece, 1... Roller table, 2 - Rail,
3. Cutting torch, 4. Cutting cart, 5. Tip detection cart,
6. Rear end detection trolley, 7. Laser light irradiation and receiver for deceleration, 8. Laser light irradiation and receiver for stopping, 9. Laser light irradiation and receiver for rear end detection Agent Patent Attorney Ya I1 : Chiyuki 1 person 3rd (a) 5 4 5 6

Claims (1)

[Claims] On the steel billet cutting and conveying line, there is a cutting cart equipped with a cutting torch, a billet tip detection truck with two pairs of laser beam irradiation/receivers for deceleration and stopping, and a steel billet rear end detection truck. The cutting cart and the tip detection cart are positioned at a distance corresponding to the planned cutting length z1, and the incoming steel l'1 is detected by the two pairs of laser beam irradiators and receivers. At the same time, the displacement of the stop position of the steel piece due to inertia is corrected by moving the tip detection cart and the cutting cart, and then the rear end detection cart detects the rear ψ1^: of the steel piece and determines the steel piece JI length. A method for cutting a long steel sheet, which is characterized in that the length is compared with a planned total length, and the cutting position is changed based on the difference.