JPH04274814A - Standby device for rolled stock waiting for cooling time - Google Patents

Abstract

PURPOSE:To attain cooling uniform in a transverse direction and to prevent the lowering of rolling efficiency by waiting time. CONSTITUTION:Forked arms 2 of a lifting means/are previously disposed between table rollers R of the transporting line on the inlet side of a finishing mill and the rolled stock requiring waiting for cooling is lifted by these arms, by which the passage of the ensuing rolled stock is allowed. The uniform cooling is executed by extruding a heat insulating cover 21 of a heat insulating means 20 into the line to cover the entire part of the rolled stock.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a standby device for rolled material waiting for cooling time, and particularly for cooling rolled material to a predetermined temperature suitable for finish rolling in the inlet conveyance line of a continuous hot finishing mill. This invention relates to a standby device for the rolled material to be used.

0002

2. Description of the Related Art Continuous hot rolling mills roll hot rolled steel sheets of various materials, and the rolling temperatures vary depending on the required product characteristics. In this case, there is no problem if slabs with approximately the same rolling temperature are continuously heated in a heating furnace and rolled continuously, but in reality, the conditions of the continuous casting process,
Slabs that require high-temperature extraction for other reasons and low-temperature extraction slabs that require low finish rolling exit temperature (FDT) are mixed together and charged into the heating furnace and heated almost simultaneously.

[0003] In the heating furnace, temperature control is performed with the high-temperature extraction slab as the control target, so the low-temperature extraction slab is also inevitably extracted from the heating furnace at a temperature higher than a predetermined temperature. In this case, the slab extracted at a temperature higher than a predetermined temperature must be descaled to obtain the required FDT, forcibly cooled using roll coolant during rough rolling or finish rolling, or The product is left to cool while waiting on a delay table on the exit side of the rolling mill.

0004

[Problems to be Solved by the Invention] As mentioned above, when a rolled material is forcibly cooled using descaling or roll coolant in order to obtain the necessary FDT, the widthwise center and side edges of the rolled material are This method cannot be easily adopted because there is a temperature difference between the parts, especially the side end corner parts of the rolled material, which are at a low temperature, which may cause material defects in the rolled product.

[0005] Furthermore, even if the rolled material is allowed to cool while waiting for some time, the side edges of the rolled material still become supercooled, which still poses a problem. However, in this case, heat insulating covers conventionally used to keep rolled materials warm
Although the above-mentioned supercooling can be prevented by using a rolling stock (No. 01, etc.), the next rolled material cannot pass through the delay table during the waiting time for cooling, which significantly reduces rolling efficiency. This has become a problem. When uniform cooling is performed using a heat insulating cover, the waiting time required for cooling becomes even longer, which has an even greater effect on rolling efficiency, and there has been a strong desire to develop a countermeasure.

SUMMARY OF THE INVENTION An object of the present invention is to provide a standby device for a rolled material waiting for a cooling time, which is capable of uniformly cooling the rolled material in the width direction and does not impede rolling efficiency at all.

[0007]

[Means for Solving the Problems] A waiting device for a rolled material waiting for a cooling time according to the present invention provides a cooling time used when cooling a rolled material to a predetermined temperature in a finishing mill entrance conveyance line of a continuous hot rolling mill. A waiting device for waiting rolled material, comprising: a lifting means having a cantilevered fork-like arm for lifting the rolled material from a table roller and making it standby; and at least the waiting rolling material, which is movable into and out of the conveyance line. The heat insulating means has a heat insulating cover that covers the upper surface of the material, and the above-mentioned problems of the conventional technology are solved.

[0008]

[Operation] Place the table from one side of the roller table to an appropriate place on the finishing mill entry side conveyor line of the hot continuous rolling mill (roller table from the heating furnace exit side to the finishing rolling machine entry side, e.g. delay table). An elevating means having a protruding fork-like arm is installed between the rollers, and the elevating means lifts the rolled material from above the table rollers. This lifting height is sufficient to allow the next rolling stock to pass between the table roller and the forked arm without any hindrance. By doing so, even if a rolled material that requires cooling waits for a certain amount of time, the next rolled material can overtake the waiting rolled material and be rolled. Therefore, rolling efficiency is not hindered at all.

[0009] At least the upper surface of the waiting rolled material is covered with a heat insulating cover of a heat insulating means to keep it warm. Although it is preferable for this heat insulating cover to cover the entire surface of the rolled material, even if it only covers the upper surface where heat dissipation is large, a sufficient effect can be obtained for uniform cooling in the width direction. According to the present invention, the waiting rolled material does not occupy the roller table, so the next rolling material can be rolled without delay, and the temperature generated in the width direction of the rolled material is reduced by using a heat insulating cover. The difference can be suppressed as much as possible.

0010

[Embodiment] An embodiment of the present invention is shown in FIGS. 1 to 4. Figure 1
is a cross-sectional view perpendicular to the conveyance line of the standby device according to the present invention, FIG. 2 is a drawing showing a part of the plane, and FIG. 3 is a cross-sectional view perpendicular to the conveyance line in another embodiment. FIG. 4 is a drawing showing a comparison of the elapsed time during standby and the temperature difference between the widthwise center and side edges of the rolled material.

In FIGS. 1 and 2, S is a sheet bar which is a rolled material, and in this case, it is stopped as S1 on a roller R of a delay table on the outlet side of a rough rolling mill (not shown). 1 is a lifting means for the seat bar S, and a roller R
between one side of the roller table (operating side in this example)
A fork-shaped arm 2 that protrudes from the seat bar S and lifts the seat bar S is attached to the arm support member 3 at an interval that is sufficient to prevent the seat bar S from being bent significantly.

The arm support member 3 is attached to the lifting frame 4, and is driven up and down together with the lifting frame 4 via a vertical shaft 7 having a male thread by a worm jack 6 driven by a geared motor 5. 8 is a frame for the geared motor 5 and the worm jack 6, and 9 is a balance weight. 10 is a heat insulating board attached to the table roller R side of the arm support member 3.

Although not shown in the figure, at least one set of such lifting drive devices is required before and after the sheet bar conveyance direction of this standby device, and each drive device is electrically or mechanically synchronously driven. It is designed so that it will be done. Further, as the driving means, it is needless to say that, instead of using electric means such as a geared motor, a driving means such as a hydraulic cylinder may be used.

[0014] Furthermore, it is preferable that an elevating guide is used for elevating and lowering the elevating frame 4 as necessary, and that the vertical shaft 7 is also protected using dust-proof boots or the like. Reference numeral 20 denotes a heat insulating means installed on the other side (in this example, the driving side of the line).A heat insulating cover 21 whose inner surface is lined with a heat insulating material 22 and whose table roller side is open is supported by wheels 23, and an air cylinder 24 is used to cover the grooves. It is configured to be movable along a shaped rail 25 made of, for example, channel steel or H-beam steel. 26 is the wheel 23
It is a supporting member of.

[0015] In this case as well, at least one set of moving drive devices is required before and after the sheet bar conveyance direction of the standby device, and the drive means thereof is not limited to an air cylinder either. In the standby device constructed in this manner, the sheet bar S to wait for the cooling time is sent onto the roller R of the delay table and stopped as shown at S1. Then, the guard motor 5 is driven, and the seat bar is lifted up by the lifting means 1 via the fork-like arm 2, and placed on standby in the state S2.

After that, the heat retaining means 20 is connected to the air cylinder 24.
The seat bar S is pushed out into the line and covered with a heat retaining cover 21. This state is shown at 21a in FIG. The seat bar S is almost completely sealed by the heat insulating board 10 attached to the arm support member 3 and the heat retaining cover 21, and is uniformly cooled. Here, it is also possible to adjust the cooling rate of the seat bar by providing holes of an appropriate size at appropriate intervals in the center portion of the heat insulating cover 21 in the width direction of the seat bar.

FIG. 3 shows an example 20' of another heat retaining means. In this example, the movement means of the heat insulating cover 27 is a swing type, and the heat insulating cover 27 is opened upward by the force of the air cylinder 30 around the pin 29 of the bracket 28 . Reference numeral 31 denotes an open/close cover for use as a heat insulator for ordinary rolled materials. The heat retaining means 20' shown in FIG. 3 has the advantage of being able to use the heat retaining means used for conventional delay tables; however, as shown in the figure, the lower surface side of the seat bar S cannot be kept warm. However, since the amount of heat dissipated from the lower surface is considerably smaller than that from the upper surface, a sufficient effect can be obtained for uniformly cooling the sheet bar in the width direction.

[0018] When the temperature of the sheet bar has decreased to a predetermined temperature and the standby state has ended, the sheet bar may be lowered onto the table roller by performing the operation opposite to that described above. FIG. 4 shows the elapsed time during standby and the difference in surface temperature between the center and end portions of the seat bar (15 mm from the end surface to the center). In this figure, it can be seen that the temperature difference in the width direction is much smaller in the case of the present invention indicated by ○● than in the case without the heat insulation cover indicated by △.

At present, the cooling waiting time in a delay table is about 15 to 20 seconds, and the target material is about 25% of the total. In this case, if the standby device of the present invention is used, the passage of the next rolled material will not be obstructed.
It was possible to improve rolling efficiency by about 2%.

[0020]

Effects of the Invention According to the standby device for rolled material waiting for cooling time according to the present invention, since the rolled material waiting for cooling time does not occupy the roller table, the next rolled material can be immediately rolled. Since the effectiveness of the heat insulating cover can be fully demonstrated, it can greatly contribute to improving rolling efficiency and product yield.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a cross section of a standby device according to the present invention perpendicular to a conveyance line.

FIG. 2 is a partial plan view of a standby device according to the present invention.

FIG. 3 is a cross-sectional view perpendicular to the conveyance line showing another embodiment of the present invention.

FIG. 4 is a drawing showing the relationship between the elapsed time during standby and the temperature difference in the width direction of the seat bar.

[Explanation of symbols]

1 Lifting means 2 Fork-shaped arm 3 Arm support member 4 Lifting frame 5 Guarded motor 6 Worm jack 7 Vertical axis 8 Mount 9 Balance weight 10 Insulation board 20 Heat retention means 21　Heat insulation cover 22 Insulation material 23 Wheels 24 Air cylinder 25 Rail 26 Support member 27 Thermal cover 28 Bracket 29 pin 30 Air cylinder 31 Opening/closing cover R Table roller S seat bar

Claims (1)

[Claims] Claim 1: A standby device for rolling material waiting for a cooling time, which is used when cooling the rolled material to a predetermined temperature in the finishing mill entrance conveyance line of a continuous hot rolling mill, which It is composed of an elevating means having a cantilevered fork-like arm for lifting and waiting, and a heat retaining means having a heat insulating cover which covers at least the upper surface of the waiting rolled material and which can go in and out of the conveying line. A standby device for rolled material waiting for cooling time.