JPS638745Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a cooling nozzle protection device in a hardening apparatus used for forced cooling of hot steel plates, such as hot rolled thick steel plates.

(Prior Art) Roller brace hardening equipment has conventionally been used as equipment for rapidly cooling and heat treating hot steel plates. A slit nozzle is usually used as the first stage nozzle of the device in order to obtain high cooling performance.

The slit nozzle sprays cooling water at an angle of approximately 20 to 30 degrees relative to the surface of the steel plate, and a roller is disposed close to the rear of the cooling nozzle. Therefore, in order to maximize the effective cooling length (running distance of cooling water), the distance between the cooling nozzle and the steel plate surface should be set as small as possible (generally 10~
30mm), the nozzle is usually fixed to the frame.

Conventional hardening equipment is directly connected to a heating furnace offline to process reheated material. Since this reheating material has a relatively good shape, even if the steel plate surface and the nozzle are installed close to each other, there have been almost no problems such as the treated steel plate hitting the nozzle until now. However, in the recent thick plate manufacturing process, the so-called temper cooling process, which combines controlled rolling with forced cooling immediately after rolling, has been put into practical use for the purpose of reducing alloying elements, saving heat treatment, and developing new steel types. The input device is installed online immediately behind the hot leveler. In this method, a steel plate rolled by a finishing mill is straightened and flattened by a hot leveler, and then cooled by a hardening device. In the above process, in order to keep the quenching start temperature as low as possible, straightening with a hot leveler is done in one pass, but ordinary steel that does not use this process does not need quenching, so it is difficult to flatten thin steel. For wood, straightening may be performed in three consecutive passes using a hot leveler. For this reason, reverse correction (2
Immediately before starting the first pass, the tip of the plate (corresponding to the rear end of the first pass) is located behind the slit nozzle, and in places where the plate shape is not very good, the plate collides with the slit nozzle while running. However, there is a risk of damaging the slit nozzle. In addition, even with very thick plates using this process, there is a possibility of collision between the plate and the slit nozzle because so-called oscillation cooling is performed in which the plate is cooled while reversing back and forth inside the hardening equipment in order to cool the inside of the plate. There is.

(Purpose of the invention) The present invention solves the above-mentioned problems, and the hardening apparatus of the present invention can pass and process even a material with a bent tip without damaging the slit nozzle.

(Structure and operation of the invention) Examples of the invention will be described below with reference to the drawings.

Figure 1 shows the equipment layout in the thick plate manufacturing process. A hot leveler 2 is arranged at the rear of the finishing mill 1 to straighten the threaded material.
Further, a hardening device 3 is disposed immediately behind the hot leveler 2 to quickly cool the plate after straightening. The first stage nozzle of the hardening device 3 consists of slit nozzles 4a and 4b arranged above and below, and rapidly cools the threaded material.

At the start of the first pass with the hot leveler 2, the plate material 5 is placed in the position shown in Fig. 2a, but at the start of the second pass (during reverse correction), the plate material 5
If the plate material 5 is in the position shown in Figure b and the plate shape is poor, the plate material 5 may collide with the slit nozzle (4a or 4b) and damage the nozzle. (Dotted line in Figure 3) This is because aprons 6a, 6a', 6 are provided before and after the slit nozzles 4a, 4b for the purpose of protecting the nozzles.
Although b and 6b' are attached,
For the reasons shown in a) and b) below, the rear apron 6b,
This is because 6b' has the slope shown in FIG.

a. During the first pass, the plate material 5 entering the hardening device 3 through the first rolls 3a, 3a' reduces the impact force when it collides with the second rolls 3b, 3b', and makes it easier to grab. To do.

b. To prevent the water spouted from the slit nozzles 4a, 4b from interfering with the aprons 6b, 6b'.

Therefore, in the present invention, a tiltable apron 7b' is provided to avoid this collision. FIG. 4 shows one embodiment of the present invention. Upper and lower aprons 7a, 7a' are attached to the upper and lower slit nozzles 4a, 4b on the front side relative to the flow of the line, and upper and lower aprons 7b, 7b', 7b'' are attached to the rear side, respectively.The apron 7b'' is attached to a frame. The apron 7b' on the side closer to the nozzle is fixed to the shaft 9, and the apron 7b' on the side closer to the nozzle is fixed to the shaft 9.
It is configured so that it can be tilted around the center. If the board enters from the first roll 3a, 3a', the apron 7
b′ is the third position by rotating it to the position indicated by the broken line.
The same slope as the apron 6b' shown in the figure is formed.

Conversely, when the plate enters from the second rolls 3b, 3b', the apron 7b' assumes the position shown by the solid line to prevent the plate from colliding with the slit nozzle 4b. Since cooling is not performed at this time, the upper slit nozzle 4a fixed to the lifting frame 10 and the upper No. 1 roll 3
a, the upper No. 2 roll 3b has already been retracted upward with respect to the pass line. Therefore, the upper apron 7b does not need to tilt and is fixed to the upper slit nozzle 4a. If the reverse rotation is performed while cooling, the upper slit nozzle 4a cannot be retracted because the plate 5 must be restrained by upper and lower rolls. Therefore, the purpose of the upper apron 7b can be achieved by having a structure similar to that of the lower aprons 7b' and 7b'', but this is not shown.

FIG. 5 shows the tilting device. An air cylinder 12 is vertically attached to the end of the lower slit nozzle 4b. The vertical movement of the cylinder rotates the shaft 9 via the arm 11. This rotation causes the lower apron 7b' to tilt. FIG. 6 shows arrow view A-A in FIG. The lower aprons 7b', 7b'' are arranged alternately in a staggered manner so that the apron on only one side does not receive all the impact force caused by the collision with the plate material 5.

Further, FIG. 7 shows a cross section BB in FIG. 5. The lower apron 7b' is prevented from moving in the lateral direction (direction perpendicular to the line) by a collar 13, and is further fixed to the shaft 9 by a key 14. On the other hand, the lower apron 7b'' is fixed to the slit nozzle 4b via the frame 8, and the shaft 9 is connected to the bush 1 in the frame 8.
5 Rotate the inner surface. Therefore, when the cylinder 12 is moved up and down, only the lower apron 7b' is tilted.

(Effects of the invention) The advantages of using the nozzle protection device according to the invention are as follows.

(1) During the reverse pass of the plate, there is no fear of the tip of the plate colliding with the slit nozzle, even if the plate is poorly shaped, allowing safe and smooth operation.

(2) Since the apron can be tilted, the plate material can be easily caught in the roll during both forward and reverse passes.

(3) Since the apron is tiltable, a large gap can be created between the slit nozzle and the apron, making maintenance of the slit nozzle extremely easy.

(4) Since the apron can be divided, widening the gap between the divided aprons allows for good drainage and prevents water from accumulating between the upper and lower aprons and reducing the nozzle cooling performance.

In addition, the protection device shown in FIGS. 4 to 7 is one of the present invention.
This is an embodiment, and it is understood that, for example, a hydraulic cylinder or an electric motor may be used instead of the air cylinder, and it is easy to change the equipment without departing from the present invention. Further, in the description of the embodiment, a device using both a fixed apron 7b'' and a tilting apron 7b' was shown, but it is also possible to configure the entire apron with a tiltable apron.Also, as described above, when performing a reversal while cooling, Since the upper slit nozzle 4d cannot be retracted because the plate material must be restrained by upper and lower rolls, the upper apron is also tilted in the same manner as the lower apron to protect the upper slit nozzle.

[Brief explanation of the drawing]

Figure 1 is a line layout diagram of the thick plate manufacturing process, Figures 2a and 2b are diagrams of the state of board jamming near the hot leveler, Figure 3 is a layout diagram of the vicinity of the conventional slit nozzle, and Figures 4 and 5. The figures are a side sectional view and a side view showing an embodiment of the present invention, FIG. 6 is a cross-sectional view taken along arrow A-A in FIG. 5, and FIG.
Figures are shown respectively. 1... Finishing rolling mill, 2... Hot leveler, 3
...Quenching device, 3a, 3a'...1st roll, 3
b, 3b'...Second roll, 4a, 4b...Slit nozzle, 5...Plate material, 6a, 6a', 6b, 6
b'...Apron, 7a, 7a', 7b, 7b', 7
b″... Apron, 8... Frame, 9... Shaft,
10... Lifting frame, 11... Arm, 12...
...Air cylinder.

Claims (1)

[Scope of utility model registration request] A hardening device that uses a refrigerant to forcibly cool a thick steel plate, and in particular in a device that has cooling nozzles for rapid cooling disposed above and below the threaded material at the entry side, the cooling nozzle for rapid cooling 1. A cooling nozzle protection device characterized in that an apron is disposed in the vicinity of the front end of the cooling nozzle, and the apron is pivotably mounted on a mount so that the apron can be tilted.