JPS6011592B2 - Hot scarfing equipment - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a hot scarfing machine that removes surface roughness from a steel billet on a rolling line, and in particular, is capable of hot scarfing only the effective part of the hot scarf. The present invention relates to a hot scarfing device.

Some of the steel slabs that have been subjected to blooming rolling cannot be used in the next process as they are due to surface defects, internal defects, or defective dimensions and shapes.

For this reason, a hot scarfing operation is performed on the rolling line to remove the surface eaves and the like. Hot scarf is the high heat generated by the exothermic reaction between Fe and 02.
The method also involves melting the gas and scattering it with an oxygen jet, which requires a large amount of oxygen gas and auxiliary fuel such as propane gas, acetylene gas, or CO gas. However, in the process before turning into billets, when the molten steel is turned into a steel ingot, the molten steel with many impurities that collects in the upper part of the ladle also
It becomes a steel ingot (crop portion) and is rolled into a steel billet. Therefore, among the steel pieces transferred on the table, a certain length range at the rear is a cropped portion of poor quality and has no value as a finished product, so there is no need to perform hot scarfing. Conventionally, the timing to end hot scarfing work was determined by visually checking the point at which the crop part reached the hot scarfing position, but it was difficult to accurately determine this timing. Therefore, there was a drawback that the timing was detected too late and unnecessary maintenance work was performed, or conversely, the timing was detected too early and good key pieces were not cleaned.

An object of the present invention is to solve such conventional inconveniences, and to provide an economical device that can automatically terminate the hot scarfing operation as soon as the cropping section reaches the working position. This aims to improve performance and quality.

The key point of the hot scarfing device according to the present invention is that the length of the cropped portion of the steel piece to be treated is determined in advance, and when the steel piece is transferred on the table, it is placed at the end of the graded piece at a predetermined position. By detecting the passage of the crotch part, the time elapsed until the tip of the crotch part reaches the working position is determined, and when that point is reached, the fuel system path is cut off and the maintenance work is automatically completed. The machine is characterized by the configuration of ancillary devices to the machine body. next,
The configuration of this device will be specifically explained. The machine body 1 includes an oxygen gas (02) supply system 11 and an auxiliary fuel supply system 12 such as propane gas (C3 day 8), and also adjusts the position of the machine body 1 up and down. It also includes a cylinder mechanism 13 for moving, but these are usually controlled by the control device 2.
It is designed to be operated by. In the present invention, the control device 2 is operated by an operation command from the crop length setting device 3. This crop length setting device 3 has a crop portion 9 of a steel piece 9 to be treated.
The length 1 of 1 is set in advance, and the gate circuit 7 described later
inputs a count signal from the controller 2, detects the point in time when the leading end of the crop section reaches the hot scarfing work position from the count value, and outputs an activation signal to the control device 2;
The work is stopped by a timer 8 after a predetermined time if necessary. On the other hand, on the upstream side of the operating position of the table that transfers the steel billet 9, a detector 4 is provided to detect the passage of the rearmost part of the steel billet, and a signal when detected is sent to the gate circuit 7. be.

A counting roller 5 is provided on the downstream side of the working position to count the conveyed length of the steel billet 9, convert it into a pulse signal by a pulse transmitter 6, and transmit it to the gate circuit 7. There is. The count value from the counting roller 5 is always input to the gate circuit 7, but the gate opens only when the detection signal from the detector 4 is input, and the count value is left unchanged. It is designed so that it can be sent to the drop length setting device 3. Next, the operation of this device will be explained.

Currently, fuel gas is supplied to the machine body 1 from the oxygen gas supply V supply system 11 and the auxiliary fuel supply V supply system 12, respectively, and the machine body 1 is supplied with hot scarf of the steel billet 9 at the working position. We are currently working on the design process. During this time, the state of conveyance of the steel pieces continues to be counted by the counting roller 5, and counting pulses are introduced into the gate circuit 7 via the pulse generator 6. As the conveyance of the steel billet progresses and the rear end eventually reaches the path of the detector 4, the detector 4 detects this and signals the gate circuit 7 that the rear end of the steel billet has reached a predetermined position. . The gate circuit 7 opens at the same time as this detection signal is input, and sends a pulse signal, which is counted after receiving the detection signal, to the crop length setting device 3. Since the working position of the machine body 1 and the set position of the detector 4 remain unchanged, and the distance L between them is a unique value, the crop length setting device 3 has the following values:
The above-mentioned eigenvalue L is set together with the length 1 of the cropped portion, and at the same time as the pulse signal is input from the gate circuit 7, the elapsed time until the leading portion of the crop reaches the working position is calculated. That is, when the length 1 of the cropped portion is subtracted from the eigenvalue L, and it is determined by the pulse measurement from the pulse transmitter 6 that the steel piece 9 has been transferred by the corresponding distance (L-1), the control A signal is issued to device 2. At this point, the leading end of the crop reaches the working position mark, and the hot scarfing operation is no longer necessary. Upon receiving the command from the crop length setting device 3, the control bag hawk 2 immediately activates the timer 8 as necessary in consideration of safety, and then controls each fuel gas supply system 11.
, 12 valves are closed to stop the supply of fuel gas (
In this case, it is preferable that the relationship between the delay times m,, L is T,>T2. ). At the same time, the cylinder mechanism 13 is also commanded to operate, and the machine body 1 is evacuated from the working area, thereby completing the hot scarfing work. According to the hot scarfing device of the present invention, it is possible to accurately determine the point in time when the cropping section reaches the hot care work position and immediately terminate the hot scarfing work, thereby eliminating fuel loss. Work can be performed economically and accurately.

[Brief explanation of the drawing]

The drawing is an explanatory diagram showing the configuration of the operation control system of the hot scarfing device according to the present invention. 1: Hot scarfing machine body, 2: Control device, 3: Crop length setting device, 4: Rear end detector of steel billet,
5: Counting roll, 6: Pulse transmitter, 7: Gate circuit,
8: timer, 9: steel piece.

Claims (1)

[Claims] 1 A hot scarfing machine, a device attached to the machine that controls the supply system of oxygen gas and auxiliary fuel, and the length of the cropped section of the steel billet to be cleaned are set in advance, and a signal is sent to the hot scarfing machine. a crop length setting device that detects the point in time when the leading end of the crop reaches a working position and instructs the control device to operate, and a detection device that detects passage of the rear end of the piece of steel being trimmed at a predetermined position;
A circuit that counts the moving length of a steel billet transferred on a table and transmits it as a pulse signal, and a crop length setting device that constantly receives the counted pulse signal and when a signal from a detection device is input. Hot scarfing is characterized by a configuration that automatically ends the injection of oxygen jet from the machine body at the same time as the top of the crop section reaches the working position. Device.