JPS6057488B2 - How to charge steel into a side-charge heating furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for charging steel materials into a side-charge type heating furnace, and more particularly to a method for automatically controlling the charging position of steel materials in the furnace.

One type of furnace that heats steel materials such as birtz, bloom, and slag to the required temperature is the side-charge type.

In this type of furnace, the steel is transported in the longitudinal direction along a charging line from outside the furnace to inside the furnace using a roller table or the like. Then, the steel material is charged into the furnace from the side of one end (inlet side) of the furnace. The charged steel is transferred to the other end (output side) of the furnace by fixed and movable hearths extending perpendicular to the charging line, and heated to the required temperature during transfer. When charging steel materials into a furnace, the steel materials must be correctly charged in the designated position to prevent the tip of the steel materials from hitting the furnace wall or from being placed too unevenly on the movable hearth. Must be.

Conventionally, a stopper was provided on the charging line in the furnace, and the tip of the charged steel material was abutted against this stopper to stop the steel material at a predetermined position. With the conventional stopper method as described above, when the length of the steel material varies greatly (for example, 2.9 to 9 m), the position of the stopper is fixed, so the steel material may vary greatly relative to the hearth depending on its length. It is stopped in a lopsided position.

In addition, when the steel materials are short, it is possible to charge the steel materials in two rows, that is, to charge the preceding steel materials into the furnace immediately after the preceding steel materials on the charging line, and to heat the two steel materials side by side. desired. However, in the above-mentioned stopper system, since there is only one stopper and its position is fixed, it is impossible to charge steel materials in two rows. Furthermore, in the stopper method, since the steel material hits the stopper, there is also the problem that the stopper is likely to fail. Instead of such a stopper method, a method may be considered in which an operator monitors the position of the charged steel material and directly controls the stopping position of the steel material.

However, this method also requires a worker, which is not preferable from the point of view of labor saving, and since the steel material is charged into the furnace, it is not possible to operate it while directly looking at the steel material, and it is difficult to operate it by monitoring the inside of the furnace such as Nv. It requires great skill to operate. This invention was made in order to solve the above-mentioned problems in charging steel materials into a side-charge type heating furnace.It is possible to automatically charge steel materials into a predetermined position in the furnace regardless of their length. , which attempts to provide a method for charging steel into a side-charge heating furnace that allows double-row charging.

In the steel material charging method of the present invention, the length of the steel material is measured while transferring the steel material at the entrance side of the furnace.

Based on this measurement, the point half the length of the steel material (the center of the steel material) is located at the center of the width of the central fixed hearth or the movable hearths arranged on both sides of the central fixed hearth (the center of the hearth). ) is calculated. Additionally, the distance of the steel material being transported is measured. Then, based on the calculated and measured values of the transfer distance, the transfer of the steel material is controlled so that the center of the steel material approximately coincides with the center of the hearth. As described above, in the steel material charging method of the present invention, the required transfer distance of the steel material is calculated based on the measured length, and the transfer distance of the steel material is further measured to determine the insertion stop position of the steel material. Therefore, even if the length of the steel varies greatly, the steel can be charged at the correct position in the furnace.

Also, make sure that the center of the steel is located at the center of the hearth. Since the steel is charged evenly against the hearth, it is possible to charge the steel in two rows.

For example, when charging one long steel material in a side-charge heating furnace in which movable hearths are arranged on both sides of a row of fixed hearths, the six centers of the steel material are approximately at the center of the fixed hearth. It is loaded so that it is positioned. Both ends of the long steel material are each supported by a movable hearth. When charging two short steel materials, they are charged so that the center point of each steel material is approximately located at the center of the movable hearth.

In this invention, since a stopper is not used for positioning the charged steel material, the above-mentioned breakage of the stopper does not occur. Further, since the steel material can be charged completely automatically, it is possible to save labor. Examples of the present invention will be described below.

FIG. 1 is a schematic plan view showing a charging device and a side charge type heating furnace. A charging device 2 is arranged on the outlet side of the receiving floor 1. The charging device 2 includes roller tables T1 to T5 arranged along a charging line 1 extending to the inside of the side charge heating furnace 3 on the entrance side. Heating furnace 3
has a central fixed hearth 4 extending perpendicularly to the charging line 1 and movable hearths 5, 6 arranged adjacently on each side thereof. Furthermore, edge fixed hearths 7 are provided on the sides of the movable hearths 5 and 6 that are not adjacent to the central fixed hearth 4.
, 8 are provided. The steel material S is transferred from the receiving floor 1 via the charging device 2 to the heating furnace 3 as shown by arrows AD. When the steel material S is long, it is transferred from the receiving floor 1 to roller tables Tl and T2, and then transferred to the roller table T4 in the furnace.
, T5. If the steel material S is short, receiving floor 1
The steel material is transferred to roller table T1 or T2, and then transferred to roller table T4 or T5 in the furnace.Next, a method for charging the steel material to a predetermined position in the furnace will be explained.I Length of steel material The measured length of is measured by means of optoelectronic switches PH1, PH2, PH3 and a pulse transmitter H°C1, which are located at the roller table T immediately before the heating furnace 3.

The photoelectronic switches PHl, PH2, and PH3 are turned on at the moment the leading end of the steel material S passes through the position of the photoelectronic switch, and turned off when the rear end thereof passes. The operation of the pulse transmitter circle C1 is controlled by signals from optoelectronic switches PHl, PH2, and PH3, and the transfer distance of the steel material S is determined from the number of pulses counted during operation. (1) In the case of a short length As shown in Figure 2 A, when the tip a of the steel material S comes to the position of the photoelectronic switch PH2 (at this time, the photoelectronic switch PH
l is already on), optoelectronic switch PH2
is turned on, and counting of pulses from the pulse generator P11, that is, length measurement is started.

Then, at the moment when the rear end b of the steel material S passes the position of the optoelectronic switch PHl, as shown in the opening of FIG. 2, the optoelectronic switch PHl is turned off, pulse counting is stopped, and the length measurement is completed. During this period, the length X1 between the steel material S(7)a<5c, that is, the transfer distance is measured. Therefore, the length 11 of the steel material is expressed by the following formula. Here, LE is the distance between the photosensors PHl and PH2.

(2) For long lengths, the measurement principle is exactly the same as for short lengths.
As shown in Figure 2, a photoelectronic switch PH3 is used instead of the photoelectronic switch PH2.

The length 12 of the steel material is expressed by the following formula. here,! is the distance between optoelectronic switches PH2 and PH3, and ! is steel material S (
7) The length is between a<5c.

In the above measurement method, the distances Ll, L between the optoelectronic switches
If 2 is accurately measured, the lengths 11 and 12 of the steel material can be measured with high accuracy because the transfer distances X1 and X2 measured by the pulse transmitter H°C1 are short. ■ Calculation of transfer distance In the case of long steel materials, the steel materials are charged so that the center Cs of the steel material approximately coincides with the center CO of the central fixed hearth.

Further, in the case of short steel materials, the steel materials are charged so that the center Cs of the steel material approximately coincides with either one of the centers Cl and C2 of the movable hearth. For this purpose, the rear end b of the steel material may be located on the entry side by one half of the length of the steel material from the center CO of the central fixed hearth or the centers Cl, C2 of the movable hearth. Therefore, the transport distance DT is determined by the optoelectronic switch PH2 or PH
It is determined by the following formula using position 3 as a reference. (1) For short lengths (transferred to roller table T)
(Transfer to roller table T) (2) For long lengths
&'A ~6i6W2啼ノ -61-However, L, , L4 and L5 are each optoelectronic switch P
From H3 to center C1 of movable hearth, center CO of central fixed hearth
and the distance to the center C2 of the movable hearth.

The calculation of DT is performed in the calculation section of the control device 9.

■ Measuring the transfer distance The transfer distance is determined by the pulse transmitter PLG2 installed at the position of the roller table T4 during the transfer of the steel material.
It is measured by counting the pulses of

For example, when feeding a short steel material to the roller table T4, pulse counting is started at the moment the optoelectronic switch PH2 is turned from on to off. The same applies to long steel materials. Further, when feeding a short steel material to the roller table T5, counting of pulses is started from the time when the photosensor PH3 changes from on to off. The pulse signal from the pulse transmitter H° C. 2 is input to the calculation section of the control device 9, where the transfer distance is calculated by counting the pulses.

(2) Control of the charging device The charging device 2 is controlled by the control device 9 so that the transfer distance becomes the target value, that is, the calculated value DT.

Before the measured value of the transfer distance reaches the calculated value, the control device/device 9
issues a deceleration command to the charging device 2, and gently stops the steel material S at a predetermined position. Further, in order to improve the capacity of the equipment, the operation of the charging device 2 is controlled so that the interval between charging steel materials is as short as possible.

[Brief explanation of the drawing]

) Fig. 1 is a schematic plan view of a charging device and a side charge type heating furnace, and Fig. 2 is a drawing explaining the principle of measuring the length of steel material. 1... Receiving floor, 2... Charging device, 3... Heating furnace,
4, 7, 8... Fixed hearth, 5, 6... Movable hearth, 9
...Control 7 device.

Claims (1)

[Claims] 1. When charging steel material into a side charge type heating furnace equipped with a central fixed hearth and movable hearths adjacent to this on both sides, measure the length of the steel material while transferring the steel material at the entrance side of the heating furnace, Based on the length measurement, the distance from the point half the length of the steel material (the center of the steel material) to the position of the center of the width of the central fixed hearth or movable hearth (the center of the hearth) Calculating the transfer distance, measuring the transfer distance of the steel material being transferred, and controlling the transfer of the steel material so that the center of the steel material approximately coincides with the center of the hearth based on the calculated value and measured value of the transfer distance. A method for charging steel into a side-charge heating furnace, characterized by: