JPH0740956Y2 - Furnace door and heating furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a furnace door and a heating furnace.

Specifically, it is to propose a furnace door that can supply a material to be rolled (hereinafter referred to as a billet as an example for convenience of description) to the rolling mill train while suppressing the influence on the environment in the furnace. Another object of the present invention is to provide a door for a furnace that can easily remove scales generated and accumulated inside the furnace.

Further, it is another object of the present invention to provide a heating furnace capable of coping with an increase in the internal quality (property) in the cross section and / or the longitudinal direction of the billet or the surface quality (property) of the billet.

Hereinafter, for convenience of description, a process of heating and rolling a billet to produce a wire rod will be described as an example.

[Prior Art] A walking beam type heating furnace (hereinafter referred to as a WB type heating furnace), an walking hearth type heating furnace (hereinafter referred to as a WH type heating furnace) in order to heat a billet and supply it to a rolling mill train. ,
The fact that a heating furnace that combines a WB type heating furnace and a WH type heating furnace, a pusher type heating furnace, etc. is used or proposed,
It is well known without citing a publication.

These heating furnaces have merits and demerits in terms of equipment cost, running cost, quality of heated billet, and other operation technology, and therefore, the present situation is that those skilled in the art comprehensively study and adopt each of them.

Recently, when the quality of the products has become more and more desired, the efforts to develop and improve the furnace have been generally focused on the major points such as the operation of the furnace and the structure and function.
It goes into every detail.

The present inventors have considered, as one of the factors that affect the quality of the product, a furnace door that can supply the billet to the rolling mill train in a state that does not affect the inside of the furnace and a furnace door that facilitates scale removal. However, the door of the furnace satisfying those conditions was not found within the scope of the investigation.

On the other hand, no heating furnace having a heat-retaining furnace provided with such a door was found. Therefore, the door of the furnace that can supply the billet to the rolling mill train in a state that does not easily affect the inside of the furnace, and the door of the furnace that facilitates the removal of the scale that is generated and accumulated in the furnace and that also causes billet surface defects, Furthermore, the cross section of the billet and /
Also, no heating furnace provided with a heat-retaining furnace capable of coping with increasing the internal quality (property) in the longitudinal direction and the surface quality (property) of the billet was not found.

[Problems to be Solved by the Invention] In view of such a background, the present invention has been made to achieve the following object.

To provide a furnace door capable of supplying a billet to a rolling mill train in a state in which the billet is hardly affected.

(EN) Provided is a door that facilitates removal of scale that is generated and accumulated in a furnace and is also a cause of billet surface flaw generation.

The above can also be achieved, and the cross section of the billet and / or
Alternatively, it is intended to provide a heating furnace provided with a heat-retaining furnace capable of coping with increasing the internal quality (property) in the longitudinal direction and the surface quality (property) of the billet.

[Means for Solving the Problems] In order to achieve such a technical problem, the present invention is characterized by being configured as follows.

That is, the first feature is that a rectangular opening having a height and a width at least through which the billet can pass is provided at the outlet of the furnace for extracting so that the diagonal line of the rectangular billet heated to a predetermined temperature is oriented in the vertical direction. It is a door of a furnace in which a large door is slidably moved up and down, and a small door having an opening similar in shape to the billet cross section through which the billet can pass is slidably moved up and down outside the large door.

The second feature is that the furnace having the above-mentioned door is a heat-retaining furnace provided in a section up to the vicinity of the entrance of the rough rolling mill through the soaking zone opening / closing door of the heating furnace.

[Operation] In the present invention, as described above, the large door is provided with a rectangular opening through which the square billet can pass, and the small door is provided with the minimum necessary opening through which the square billet can pass and which is similar to the billet cross section. Since the double doors are combined so that they can slide up and down, the heat dissipation area can be minimized by opening the small door even if the opening of the large door has a margin when the billet is extracted. In addition, it is possible to prevent heat loss and always maintain a stable state in the furnace.

[Embodiment] First, a furnace door according to the present invention will be described.

As shown in FIGS. 1 to 4, the billet 2 is provided at the outlet of the furnace 1.
A large door 4 having an opening 3 larger than the cross-sectional dimension thereof is slidably movable. Then, a small door 6 smaller than the opening 3 and having a shape similar to the cross section of the square billet 2 and having a minimum size 5 through which the billet 2 can pass is slid by a guide body 7 on the outside of the large door 4. Provide freely.

In FIG. 2, the billet 2 is allowed to pass through the opening 5 of the small door 6 in a diamond shape (the diagonal line of the billet is in the vertical direction) (three billets are shown in the figure, but the number is not limited). It has an opening shape.

These large doors 4 and small doors 6 have the wire 1
The drums 8 and 9 are hung from the drums 8 and 9 via the drums 0 and 11.
Is connected to the drive units 12, 13 as shown in FIG.

In the figure, 14 is a conveying means in the furnace, 15 is a scale generated in the furnace, 16 is a container for receiving the scale, 17 is a scraping jig,
Reference numeral 18 indicates a stand, and 19 indicates a work floor.

The present invention thus configured operates as follows.

Description of the operation of the door when supplying the billet from the furnace to the rolling mill train: When supplying the billet 2 in the furnace 1 to the rolling mill train (not shown), the opening 5 of the small door 6 is opened as shown in FIG. The drive device 12 rotates the drum 8 until it coincides with the opening 3 of the large door 4, and the wire 10
Roll up and down. At this time, the small door 6 presses the outer side with the guide body 7 and the inner side is in contact with the outer side of the large door 4, so that the large door 4 and the guide body 7 are brought into contact with each other and slide up and down. In the present invention, this is called sliding up and down.

The opening 5 of the small door 6 has a minimum size necessary for the billet 2 to pass therethrough (in the present invention, the opening 5 is smaller than the opening 3 of the large door 4 and larger than the cross section of the billet 2). , The inside of the furnace is exposed to the minimum required. Therefore, due to the effect of the pressure inside the furnace, the atmosphere enters the furnace and the environment inside the furnace, such as the atmosphere inside the furnace, the temperature inside the furnace, etc., is not easily affected,
The billet 2 can be fed to the rolling mill train.

Description of the operation of the door when removing the accumulated scale from the inside of the furnace: As shown in FIG. 4, both the large door 4 and the small door 6 slide up together and rise from the furnace bottom to the large door 4 and the small door 6. Open up. That is, the driving devices 12 and 13 are simultaneously driven to rotate the drums 8 and 9, and the wire 1
Roll 1, 12 and slide up and down the large door 4 and small door 6 at the same time. Other examples of sliding up / down are large door 4 → small door 6, small door 6 → large door 4
Can be made in the order
It can be appropriately selected by the operation of 3, but for implementation, select the one that is more advantageous according to the work purpose.

A scale 15 for depositing by operating a scraping jig 17 from the open portion of the furnace bottom that occurs after raising and lowering the large door 4 and the small door 6.
Is removed to container 16.

The conventional furnace has a problem in that it is impossible to remove the accumulated scale in the vicinity of the exit where the door is located, that is, the open part cannot be formed in the bottom of the furnace. For this reason, the deposition scale may reach the level of the transportation means, and may impair the surface quality (property) of the billet. Moreover, the removal of the deposited scale had to be done by interrupting the operation of the furnace.

The present invention solves this problem by sliding the large door 4 and the small door 6 up and down to provide an open portion at the bottom of the furnace.

Now, the second feature of the present invention is that the billet is supplied to the rolling mill train without affecting the environment in the furnace and the scale is easily removed.
Or internal quality (property) and surface quality (property) in the longitudinal direction
It is also possible to deal with the higher quality of cars, which is shown in Figs.
This can be achieved with the embodiment shown.

FIG. 5 is an explanatory view showing an outline of the WB type heating furnace 20, which is cut from a side surface, and includes a charging device 21, a roller table 22, and a pre-heat zone.
23, the heating zone 24, the soaking zone 25, the first WB 26, the second WB 27, the extraction roller table 28, the extraction straightening device 29, the convection fan 30, the upper zone axial flow burner 31, and the lower zone axial flow burner 32 are shown.

As shown in the perspective view of FIG. 6, there is an extraction roller table 28 of the soaking zone 25 when the heating furnace 20 as a whole is further viewed from the direction of the pinch roll 33 on the rough rolling mill side in FIG. A heat-retaining furnace (35) is detachably attached to the extraction port (34) through an opening / closing door.

This heat-retaining furnace 35 is provided with a billet conveying means, for example, a roller table capable of withstanding heat-retaining temperature inside, a heat-retaining burner 36 above the level, and a lid 37 that can be opened and closed.
A scale outlet is provided below the billet conveying means.

A billet extraction port 38 as shown in FIGS. 7 and 8 is provided at the tip of the heat-retaining furnace 35, that is, at a portion facing the pinch roll 33.

That is, FIG. 7 is a view as seen from the pinch roll 33 side, and an air cylinder 40 is attached to the right side of the tip of the heat insulating furnace 35 with the piston rod 39 facing upward. A guide wheel 41 is mounted on the tip of the guide wheel 41.

On the other hand, a small door 44 having an opening 43 having a size larger than the sectional shape of the billet 42 is attached to the heat-retaining furnace 35 as shown in FIG. . In the illustrated example, three openings 43 are arranged side by side so that they can be supplied to the dies of the rolling mill.

The large door 45 is fitted inside the small door 44 having the opening 43, and the large door 45 and the tip of the heat insulating furnace 35 are attached by a guide body 47 so as to be slidable in the vertical direction and moved up and down.

The small door 44 and the large door 45 are attached with wires 48 and 49 respectively on the upper portions thereof, and the air cylinder 5 is inserted through the guide wheels 50 and 51.
It is connected to 2,53 piston rods 54 and 55.

Therefore, when opening / closing the billet extraction port 38, when the air cylinder 52 is operated to retract the piston rod 54, the wire 48 moves along the guide wheel 50 and slides the small door 44 on the surface of the large door 45 having the opening 46. Then, it rises upward to expose the opening 43. In this operation, since the guide body 47 presses the contact surface of the small door 44, even if the small door 44 slides on the surface of the large door 45 having the opening 46, a gap is created or rattles. It plays the role of preventing movement.

The opening 43 is in an open state during the extraction of the billet 42, but since the size is slightly larger than the billet 42, the furnace pressure of the heat retention furnace 35 also acts and the outside air enters. Suppress and prevent

When the extraction of the billet 42 is completed, the air cylinder 52 is operated, the small door 44 is lowered in the opposite manner to the previous operation, and the opening 43 is closed.

Since the heat retaining furnace 35 has a different heat retaining temperature depending on the type of the billet 42, the heat retaining burner 36 is controlled and the furnace is operated according to a predetermined work standard.

The heat-retaining furnace 35 plays a role of preventing decarburization of the billet 42 from the soaking zone 24 and further promoting thermal diffusion to eliminate a temperature difference in the cross section and / or the longitudinal direction of the billet 42. In addition to the above, depending on the type of the billet 42, it also has a role of contributing to making the inclusions harmless in plastic working.

The billet 42 is heated by the WB type billet heating furnace 20 according to the present invention as follows.

The billet 42 on the roller table 22 is loaded into the furnace by the loading device 21. Billet 42, which reached the pre-tropical zone 23, is the first WB2
The action of 6 heats the billet 42 while transporting it to the heating zone 24 and the action of the second WB 27 to the soaking zone 25 while preventing decarburization. The convection fan 30 makes the furnace temperature uniform and contributes to decarburization prevention heating.

The billet 42 is extracted by the operation of the extraction straightening device 29 to the extraction roller table 28 while straightening if there is a bend in the longitudinal direction,
Transfer to the heat retention furnace 35 through an outlet not shown.

Inside the heat-retaining furnace 35, there is a transporting means, which is suitable for a moving speed suitable for the heat-retention time, a rough rolling mill, a moving speed suitable for the speed of the pinch rolls 33, or the operating conditions of the rolling mill train, and for solving troubles. Temporarily stop moving to keep fit.

In the heat retention furnace 35, as described above, the temperature difference in the cross-sectional direction and / or the longitudinal direction of the billet 42 is eliminated. Also, some inclusions are rendered harmless.

The billet extraction port 38 of the heat retention furnace 35 is opened and closed by the operation described above to supply the billet 42 to the pinch roll 33 while preventing outside air from entering.

As described above, the present invention is a heating furnace provided with the heat-retaining furnace 35 having the furnace door described in the first feature. Therefore, in addition to the technical problem, action, and effect of the first feature, thermal diffusion By billet 42
It is possible to prevent temperature unevenness in the cross section and / or the longitudinal direction. Therefore, the internal quality (property) and the surface quality (property) can be improved, and the purpose is achieved.

[Effects of the Invention] Therefore, the billet heating furnace of the invention has the following effects.

Since the heat-retaining furnace is continuously installed in the soaking zone,
Since the heat diffusion can be promoted, the temperature difference in the cross section and / or the longitudinal direction of the billet can be eliminated. Some inclusions can be modified to be harmless by plastic working.

Therefore, the quality of wire rods, the quality of secondary processed products, and the quality of tertiary processed products can be increased.

Since the billet extraction port of the heat retention furnace is only opened to the minimum required for the billet to pass, it is possible to suppress, for example, outside air from entering and damaging the inside of the furnace.

Therefore, the furnace temperature is stable and the atmosphere is stable, so that the cost of the furnace can be reduced. Also, with the stabilization of the furnace, the quality of the billet during heat retention can be achieved according to the heat retention purpose.

[Brief description of drawings]

The drawings are all related to one embodiment of the present invention. FIG. 1 is an explanatory view showing a cross section of a door provided at the exit of the furnace, FIG. 2 is a view taken along the arrow AA ′ of FIG. 1, and FIG. Fig. 1 is an explanatory view showing a cross section of the small door slidingly moved up and down, Fig. 4 is an explanatory view showing a cross section of the large door shown in Fig. 1 slidingly moved up and down, and Fig. 5 is a billet. Explanatory view of the heating furnace cut along the length of the furnace, FIG. 6 is an enlarged perspective view of an essential part of the billet heating furnace seen from the side of the rough rolling mill, and FIG. 7 is a pinch of the heat-retaining furnace portion of FIG. FIG. 8 is an explanatory view seen from the roll side, and FIG. 8 is an enlarged explanatory view of an essential part seen from the direction of arrow AA ′ in FIG. 1 ... furnace, 2 ... billet, 3 ... opening, 4 ... large door,
5 ... Opening, 6 ... Small door, 7 ... Guide, 8 ... Drum, 9 ... Drum, 10 ... Wire, 11 ... Wire, 12 ...
… Drive device, 13 …… Drive device, 14 …… In-furnace transportation means, 15
…… Scale, 16 …… Container, 17 …… Scraping jig, 18…
… Stand, 19 …… Work floor, 20 …… WB type heating furnace, 21 …… Charging device, 22 …… Roller table, 23 …… Preheating zone, 24 ……
Heated zone, 25 …… Soaking, 26 …… 1st WB, 27 …… 2nd WB, 28
…… Extraction roller table, 29 …… Extraction straightening device, 30…
… Convection fan, 31 …… Upper axial fan, 32 …… Lower axial fan, 33 …… Pinch roll, 34 …… Extraction port, 35…
… Heat-retaining furnace, 36… Heat-retaining burner, 37… Lid that can be opened and closed, 38
…… Billet extraction port, 39 …… Piston rod, 40 …… Air cylinder, 41 …… Guide wheel, 42 …… Billet, 43 …… Opening, 44 …… Small door, 45 …… Large door, 46 …… Opening , 47 ... Guide, 48 ... Wire, 49 ... Wire, 50 ... Guide car, 51 ...
… Guide car, 52 …… Air cylinder, 53 …… Air cylinder,
54 …… Piston rod, 55 …… Piston rod

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Yoichi Senda 23-15, Suzuko-cho, Kamaishi-shi, Iwate Prefecture Kamaishi Steel Co., Ltd., Nippon Steel Co., Ltd. 1-1-1 Inside Nippon Steel Co., Ltd. Equipment Technology Headquarters (72) Inventor Murafumi Kobun 2-4-7 Kyomachibori, Nishi-ku, Osaka City, Osaka Prefecture Chugai Furnace Industry Co., Ltd. (72) Inventor Susumu Takasaki Osaka Prefecture 2-4-7 Kyomachibori, Nishi-ku, Osaka City Chugai Furnace Industry Co., Ltd. (56) References: Actual development Sho 54-129507 (JP, U) Actual public Sho 56-3326 (JP, Y2)

Claims (2)

[Scope of utility model registration request] 1. A large door provided with a rectangular opening having a height and a width that allow at least the billet to pass through at the outlet of a furnace for extracting so that the diagonal line of the rectangular billet heated to a predetermined temperature is oriented in the vertical direction. A door for a furnace, which is provided so as to be slidable up and down, and a small door having an opening similar in shape to the billet cross section through which the billet can pass is slidably lifted outside the large door. 2. A furnace having a door according to claim 1, which is a heat-retaining furnace provided in a section from the soaking zone of the heating furnace to the vicinity of the entrance of the rough rolling mill. .