JPS59197516A - Transfer of bloom or slab in walking beam reheating furnace - Google Patents

Abstract

PURPOSE:To transfer a slab on bloom freely changing materials gap and transfer speed, by a method wherein the slab on bloom is transferred between the beams operating a suitable transfer distance by detecting the position of slab or bloom on the before stage beam in a split-type reheating furnace and then the after stage beam is operated. CONSTITUTION:Slabs on blooms 2e and 2f to be transferred are charged by an optional gap onto the before stage beam 1a of split-type reheating furnace. The position of slab on bloom 2e is detected with a detector 12 and the slab on bloom 2e is transferred between the beams operating the transfer distance from the detector 12 until the gap between the slab on bloom 2e and the slab on bloom 2d on the after stage beam 1b becomes a settled gap G. Then, the slab on bloom 2e is transferred to the original position of transferred slab on bloom 2d within the beam by operating the after stage beam. Those transfer between the beams and transfer within the beam are alternately carried out and the transfer between the beams is carried out by a fixed gap. By this method, the material transfer speed can be optionally changed and the utilization efficiency of reheating furnace can be improved in walking beam reheating furnace.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for transporting materials in a walking beam heating furnace in which a movable beam is divided into a plurality of parts in the material advancing direction (hereinafter referred to as a divided heating furnace).

Recently, steel slabs produced by continuous casting equipment or blooming are subjected to direct rolling, in which they are subjected to the rolling process as hot slabs, or they are first charged into a heating furnace in the hot slab state, heated and soaked, and then rolled. A hot charge is now available.

By the way, in the case of hot charging, the higher the temperature of the material to be heated, the faster it passes through the low-temperature area near the entrance of the heating furnace, and intensive heating and soaking in the high-temperature area of the heating furnace prevents heat dissipation. It is desirable to do so.

Furthermore, it is desirable to change the material transfer speed within the heating furnace from the viewpoint of preventing scale defects, material properties, and energy saving.

Conventionally, a walking beam split heating furnace has been used as a means to change the transfer speed of materials in the furnace, and this has been done by changing the number of cycles of each movable beam. However, in this conventional operation method, the stroke (advance length) of the movable beam is fixed at a constant length, so it can only be applied when the width of the material is constant, or it is difficult to adjust the material spacing. There are drawbacks such as the amount being limited to an integer multiple of the stroke of the movable beam, and the utilization efficiency of the heating furnace was extremely poor.

The present invention provides a novel method in which the spacing between materials can be freely changed and the transfer speed can be freely changed when transferring materials onto opposing movable beams even if the materials have different widths in a split heating furnace. The purpose is to provide a convenient transportation method.

Embodiments of the present invention will be described below with reference to the drawings. 1st
The figure shows a split-type heating furnace for implementing the present invention, and shows an example in which the movable beam is divided into two parts: a front stage (charging side) and a rear stage (extraction side). The steel billet 2 transferred to the front side of the heating furnace by the charging table 3 is charged into the furnace via the fixed skid 5 by the charger 4. The front beam 1a and the rear beam 1b are supported by support struts], Oa, and 10b, respectively, and the base of the strut to each support 1 is connected to a truss 6a.
.

It is fixed at 6b. 7a, 7b are vertical drive cylinders, and the trusses 6a, 6b are connected to a crank mechanism 8a,
It moves up and down via 8b. Reference numerals 9a and 9b denote forward and backward drive cylinders, which are connected to the trusses 6a and 6b, and are configured to drive the trusses back and forth by setting an arbitrary amount of forward and backward movement.

The front beam 1a and the rear beam 1b independently move the steel pieces 2 on the fixed skid 5 from the charging side while performing a rectangular movement in which one cycle is ascending, advancing, descending, and retreating. Transfer in the extraction side direction (arrow X direction). 1.
1a, 1], b are celsin encoders provided to measure the amount of forward and backward movement of each of the front and rear beams.

12 is a steel piece detector (hereinafter simply referred to as a detector),
Known detectors, such as H, M, D, etc., can be used to detect the position of the billet transported by the pre-beam.

The mounting position of the detector 12 may be above, below, or to the side of the front beam 1a, but in the transport direction, as shown in FIG. Any position may be used as long as it is within the operating range of the extraction direction movement limit position (imaginary line y+ in FIG. 6), but it is desirable to be as close to the end as possible in view of transport tracking errors.

13 is an egistractor for extracting the steel pieces in the furnace onto the extraction table 14.

Next, a specific method of implementing the present invention using the split-type heating furnace configured as described above will be explained. Figure 2a shows the transported steel piece 2e.
, 2f have already been charged onto the front beam la at an arbitrary spacing between steel slabs, and the steel slabs 2a to 2d have already been arranged at a constant spacing G on the rear beam 1bJ: by the method described later. shows.

Note that the rear beam 1b at this time is retracted and stopped on the most extraction side, and the rearmost steel piece 2d is placed in a position that does not interfere with the operation of the front beam 1a, and the rear end surface of the steel piece 2d (
The separation distance Lb between the charging side) and the detector 12 is determined by calculating the beam transfer ratio 9IL from the time when the steel billet 2d turns off the detector 12, but it can be determined by any method.

Now, in the following example, the steel piece 2e on the front beam Ia is conveyed in the extraction side direction, and the rearmost steel piece 2d on the rear beam lb is conveyed.
In the first stage (beam-to-beam transfer), the steel billet 2e is further transported to the same position where the previous steel billet 2d was placed. The process up to this point will be described as the second stage (transfer within the beam).

First, in the first stage, if only the front beam 1a is operated independently from the state shown in FIG. 2a, the state shown in FIG. 2b will be obtained after the first stage of conveyance is completed. The positional relationship after this conveyance is completed is as shown in the following equation (1).

L t = L b -G (1) However, Lt: Distance (rn m) that the steel piece 2c is conveyed after turning on the detector 12 r-b: Above the rear beam Jb Distance between the rear end surface of the steel slab 2d and the detector 12 (min) G: Steel slab interval (mm
) Note that the required transport distance FJI L t requires the following limiting condition of equation (2). In other words, the steel piece 2 is attached to the front beam 1a.
This is because when lifting and transferring the steel piece, if the overhang allowance α is not determined based on the positional relationship between the center of gravity of the steel piece and the tip of the beam, there is a risk that the steel piece will fall from the beam. The actual overhang allowance is 1 of the width of the billet.
It may be in the range of 73 to 1/4.

+α for Lt≦ (2) However, K: front stage beam 1 located on the heavy oil outlet side from the detector 12
Distance to the front end of a (mm) α: Allowable overhang from the tip of the beam (mm
) Hereinafter, a specific method of controlling the required conveyance distance FJltLt of the steel billet 2e by the front beam 1a will be explained with reference to FIGS. 3 and 4.

Let Ll be the distance between the front end surface of the steel billet 2e to be conveyed at the current position and the detector 12, then as long as Ll satisfies the condition of equation (3), the front beam 1a is turned to the maximum input 1-roke S. Activate it with.

L1≦N+α−... (3) However, Ll: Distance (mm) between the front end surface of the M14 piece 2e at the current position and the detector 12. N: Detection when the front beam 1a is on the heavy loading side. vessel +2
Distance from to the front end of the front beam 1a (mm) Now, when the front beam 1a reaches the heavy oil output end, L+<L
If t and the condition of the following equation (4) is satisfied, then the following step 1
- If the rake is operated at the maximum stroke S, there is a risk of the steel piece falling, so the next strokes must be operated at the stroke S1, which is smaller than the maximum stroke S.

For this reason, the retreat iM of the front beam in preparation for the first transport is determined by the following limiting condition of equation (5).

L+>N+α・・・・・・・・・ (4) Ln≦M≦, −L, 10α− (5) However, M: Beam retreat amount just before the final stroke of the front stage beam (mm) Ln: Required transport Remaining transfer amount of distance Lt (mm) In the above process, at the position where L+=Lt, the front beam 1
If step a is stopped, the inter-beam transfer of the copper piece 2e is completed, and the distance between the steel piece 2e and the S piece 2d on the subsequent beam 1b is placed at a constant interval G.

Next, the preceding beam], the succeeding steel piece 2f on a is attached to the steel piece 2
In preparation for conveyance in the same manner as in e, the steel piece 2e that has been transferred between beams is once conveyed to a standby position, but in this specification, this conveyance is referred to as intra-beam conveyance. That is, the steel piece 2e is transferred so that the distance between the rear end surface of the steel piece and the detector 12 becomes the waiting interval Lb.The procedure will be explained with reference to the flowchart of FIG.

When transporting the standby interval Lb, the rear beam 1b and the front beam 1a are moved individually by the value of r-b that satisfies the following equation (6), or the rear beam 1b and the front beam 1a are connected as necessary. Operate and transport.

G≦L b≦l (1α10, Lb≧K...(6) By the way, if the next set piece 2f following the steel piece 2e is in the range where it interferes with the operation of the rear beam 1b, , when the rear beam lb is operated at the maximum stroke S, the rear beam 1b
Since there is a risk of partially lifting the next steel piece 2f due to the rising operation of the steel piece, the rear beam 1b is operated independently in a small loaf S' of the steel plate in a small range that does not interfere with the next steel piece 2f. While checking the current distance L2 between the rear end face and the detector, the robot stops at the position where the copper piece position becomes rb.

At this time, the front beam 1a is retracted to the heavy loading side.

Further, when the next set 2f does not interfere with the operating range of the rear beam 1b, it is checked whether the next set 2f is in the range where it will interfere with the rear beam 1b in the next beam operation.

If it is within the range of interference, or if you do not want to operate the front beam 1a at the same time even if it is not within the interference range, check whether the center of gravity of this piece 2e is within the operation range of the rear beam 1b. If it is not within the operating range, connect the front and rear beams and move the steel piece 2e to a position where it does not interfere with the next set or rear beam lb, and so that the center of gravity of the steel piece 2e is at the rear beam retreat amount. do.

After that, the front stage beam 1a is retracted to the heavy loading side, and the position where the billet position becomes Lb by independent operation of the rear stage beam 1b, including when the above-mentioned center of gravity position is within the operation range of the rear stage beam. to stop the transfer.

When the next beam 2f does not come into the range where it will interfere with the subsequent beam 1b during the next beam operation, and during operation, the first beam 1
If you want to operate a as well, connect the front and rear beams,
When the steel billet position reaches Lb, the transfer ends. During this connection operation, the next steel piece 2f may come into the range where it will interfere with the subsequent beam 1b in the next beam operation before the steel piece position reaches Lb. At that time, the same process as described above, that is, the process of moving the center of gravity of the steel piece 2e when it is necessary to move it, and the transfer of the latter beam 1b alone are performed. .

Through the above-described first step (inter-beam transfer) and subsequent second-step (intra-beam transfer) transfer process, the spacing between the steel slabs on the subsequent beam ib is set to the desired spacing G shown in FIG. 2c. Therefore, from now on, inter-beam transfer and intra-beam transfer may be repeated alternately. Of course, during the above-mentioned transfer operation, it is possible to extract a new succeeding steel billet into the furnace at any time at the tip of the front or rear beam lb.

Although a control mechanism for carrying out the present invention is not particularly illustrated, the control mechanism for implementing the present invention includes the detector 12. Sershin encoder 11a
, llb, drive cylinders 9a, 9b, etc., and a well-known electronic computer system, an automatic or semi-automatic control system can be adopted as necessary. Furthermore, although the example shows the case of a split-type heating furnace in which the movable beam is divided into two, in the case of a heating furnace in which the movable beam is divided into three or more, the mutual relationship between the front and rear beams may be replaced. It goes without saying that the present invention can be carried out by using only the following.

According to the present invention, even if the spacing between the steel slabs on the front beam is random, any spacing between the steel slabs can be set when transferring the steel slabs to the rear beam, so the utilization efficiency of the heating furnace is extremely high.
The fuel saving effect is also large.

[Brief explanation of drawings]

FIG. 1 is a side view schematically showing a divided heating furnace for implementing the present invention. FIGS. 2a, 2b, and 2c are side views showing the conveying process of the steel billet. FIG. 3 is an enlarged side view showing the positional relationship of the beam-to-beam transfer process. FIG. 4 shows flowcharts 1-- of the inter-beam transfer operation, and FIG. 5 shows flowcharts 1-- of the intra-beam transfer operation. FIG. 6 is a side view showing the installation position of the detector. 1a: Front beam lb: Back beam 2: Steel piece
3: Charging table 4: Bushosha-5 = Fixed skid 6a, 6b Nidras 7'a, 7b: Drive cylinder 8
a, 8b: Crank mechanisms 9a, 9b: Forward and backward drive cylinders 10a, 10b: Support struts 11a, llb: Selshin encoder 12: Slab detector 13: Extractor 14 2 Extraction table helmet 67 K'2゜400th

Claims (1)

[Claims] A method for transporting a steel billet between the movable beams of a walking beam heating furnace in which the movable beam is divided into a plurality of parts in the direction of transport of the billet to be conveyed, the method comprising: determining the position of the billet on a former beam of the movable beam; A detector is provided to detect the forward beam, and the conveyance distance from the detector is increased until the distance between the conveyed piece of steel on the beam and the conveyed piece of steel on the latter beam reaches a predetermined interval. While performing calculations, the beam is transferred between beams, and then the subsequent beam is operated to transfer the transferred steel piece within the beam to the original position of the transferred steel piece. After that, inter-beam transfer and intra-beam transfer are performed alternately, and the beam is transferred at a constant rate. A method for transporting steel billets in a walking beam heating furnace, characterized by transferring steel billets between beams at intervals of .