JPS6112819A - Continuous furnace for heat treatment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a new and improved construction of a continuous furnace for heat treating metal articles such as billets, bars, etc., in particular aluminum billets. A walking device that is used to heat-treat metal articles such as those mentioned above, and is connected to a support that extends from outside the furnace into the inside of the furnace through a through hole formed in the hearth, and is moved by this support. - Concerning a new and improved structure of a continuous heat treatment furnace equipped with a beam.

In this specification, the term "aluminum" refers to
In addition to pure aluminum, aluminum alloys are included.

PRIOR ART AND ITS PROBLEMS Continuous furnaces of the type described above achieve the purpose of heating and holding metal articles to be heat treated at a predetermined holding temperature or full annealing temperature before further processing.

The aluminum billet is heated in this continuous furnace, for example for a homogenization step during subsequent processing in a subsequent processing furnace.

In known continuous furnaces in which long aluminum billets are maintained at a predetermined temperature, the billets are continuously introduced into the continuous furnace and then conveyed through the furnace. During the transport operation, the billet is maintained at the predetermined annealing temperature with heated air using a blower device. The elongated aluminum billet or other elongated metal article to be heat treated is placed in the groove or groove of the fixed support beam with its axis perpendicular to the predetermined transport direction.

During an article transport operation, the metal article to be heat treated is first lifted from a fixed support beam by a walking beam. The walking beam transports the material to be heat treated in a lifted state by a predetermined length in the transport direction, and then places it on the fixed support beam again. Each walking・
The beam returns to its original position and a new cycle of transport process begins. The walking beam is located inside the continuous furnace and is moved and guided by support means consisting of vertical struts extending through through holes in the hearth. These ram-like columns are connected to a moving and elevating drive means provided outside the continuous furnace, and are operated by this means.

A large amount of heat is lost through the through holes formed in the hearth that are necessary to allow movement of the struts. Usually, one A-
The king beams must be arranged in a relatively narrow space to avoid deformation of the materials to be heat treated, i.e. the metal articles to be heat treated, and the length of these materials is
Due to their length of several meters, a large number of posts are required to support the walking beam.

Therefore, the number of through-holes required increases;
The overall loss of thermal energy is quite significant.

Conventionally, in order to prevent the above-mentioned loss of thermal energy,
The through holes were sealed using an elastic material combined with a seal. The elastic material can deform in response to the movement of the strut and seal the through hole. However, there is a problem in that this method cannot significantly reduce heat loss.

Furthermore, this elastic material is subject to severe wear and must be replaced frequently, resulting in increased repair costs.

The object of this invention is to develop a new continuous furnace for heat treatment, which is capable of maximally preventing and reducing heat loss through the through-holes formed in the hearth, which are required for the movement of walking beams and supports. and to provide an improved structure.

Another object of the present invention is to provide a through-hole formed in the hearth with a long service life and low repair costs in order to prevent and reduce the heat loss as described above to the maximum extent possible. The object of the present invention is to provide a new and improved construction of a continuous furnace for heat treatment, which is provided with low sealing means.

Furthermore, other objects of the invention will become apparent as the following description progresses.

Means for Solving the Problems The continuous furnace for heat treatment according to the present invention includes a walking beam for moving the metal article to be heat treated almost horizontally within the furnace, and a structure for moving the walking beam together with the walking beam. The support means are connected to each other, a hearth having a through hole through which the support means is passed, and a cover means arranged in contact with the hearth so as to seal the hearth. The movement causes the walking beam to move in a substantially horizontal direction for transporting the metal article to be heat treated, and the support means is slidably passed through the cover means in a vertical direction and is moved together with the cover means. and the cover means is movable in a substantially horizontal direction by substantially horizontal movement of the support means, and when the cover means is moved in a substantially horizontal direction by the support means, the substantially horizontal movement of the cover means The through hole in the hearth is covered by the cover means during the directional movement.

In the above, it is preferable that the cover means is in contact with the lower surface of the hearth. In this way, when adjustment or replacement of the cover means is required, the cover means can be easily accessed. Further, it is preferable that the cover means is provided with a guide roll for raising and lowering the support means, and that this guide roll for raising and lowering the support means is brought into contact with the support means adapted to interlock with the cover means.

This reduces friction during the vertical movement of the support means through the cover means and also allows the cover means to be accurately horizontally moved during horizontal movement of the support means. It becomes possible to move. Also,
Preferably, the cover means is provided with a guide roll for horizontal movement of the cover means, which guides the cover means as it moves in the horizontal direction. Preferably, the guide roll runs on a horizontal rail extending approximately parallel to the hearth. Preferably, the covering means also comprises a metal box containing, preferably filled with, insulation material. In the portion facing into the hearth, the heat insulating material is preferably a heat-resistant heat insulating board. In case of wear, this insulation plate can be easily and quickly replaced individually.

Furthermore, it is advantageous for the cover means to be provided with an adjusting screw so that the cover means can contact the hearth precisely with a slight contact pressure. The adjustment screw allows the cover means to be readjusted and also compensates for any wear that occurs as a result of relative movement between the cover means and the hearth providing a slightly abutting and slidably abutting seal. can. Furthermore, the formation of voids or gaps is prevented, so that ideal coverage and insulation can be obtained.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings, although simplified, depict a continuous heat treatment furnace to the extent necessary for those skilled in the art to readily understand the basic principles and concepts of the invention.

FIG. 1 shows a typical embodiment of the continuous furnace of the present invention, and is a sectional view taken along a vertical plane parallel to the conveyance direction of the material to be heat treated (metal article to be heat treated). The continuous heat treatment furnace (1) consists of a rapid heating furnace supported by a base part (17). In a typical embodiment, the material to be heat treated is an aluminum billet with a circular cross section, but it may also be an aluminum billet or an aluminum bar with a square cross section. It goes without saying that the material to be heat treated may be a metal article of any suitable shape made of a metal or alloy other than aluminum.

The material to be heat treated is introduced into the continuous heat treatment furnace (1) from the left side in Fig. 1, and is transported through the continuous furnace (1) in the transport direction shown by the arrow (4) in Fig. 1. ) to reach the discharge side provided on the right side. In the exemplary embodiment shown, the material to be heat treated consists of a so-called long aluminum billet (3) of circular cross section. The aluminum billet (3) has a diameter of 260 ml and a length of 7500 mm. Charging of the aluminum billets 1-(3) is carried out using hot air, and billet transport is carried out in the furnace (1) by nozzles (5) and (6) provided at the top and bottom of the transport path of the aluminum billets (3), respectively. It is heated and maintained in a heated state by medium hot air. During this process, for example, a continuous furnace (1
) in any suitable manner, such as by selecting a residence time in
The required temperature is maintained for one hour.

As is clear from Figure 2, aluminum billet (
The axis line of 3) is horizontal and faces in a direction perpendicular to the conveying direction. The transport of the aluminum billet (3) in the continuous furnace (1) is achieved by the walking beam principle.

Therefore, the aluminum billet (3) is first placed in an initial position on a fixed support beam (8) extending along the conveying path. A number of walking beams (10), six A-king beams (10) in the exemplary embodiment shown, also extend along the transport direction (4). The aluminum billet (3) is lifted by a walking beam (10) from its initial position on the fixed support beam (8) shown in FIG.

The aluminum billet (3) is then transported a predetermined distance in the transport direction by horizontal movement of the walking beam (10). Then, by lowering the walking beam (10), the aluminum billet (3) is lowered again and placed on the fixed support beam (8). During this operation, the billet support surface of the walking beam (10) is lowered below the billet support surface of the fixed support beam (8), after which the walking beam (10) is returned to its initial position again.

The above operations are carried out cyclically until all the aluminum billets (3) have passed through the continuous furnace (1) and are sent from the continuous furnace (1) to subsequent processes, such as homogenization furnaces, presses, etc. Repeated.

The blower (12) collects the heated gas after conducting a predetermined amount of heat to the material to be heat treated, and transfers the cooled gas to the conventional
Therefore, the gas is guided to a heat source with a structure not specifically shown, and the heated gas is again blown onto the material to be heat treated, for example, the aluminum billet (3), through the nozzles (5) and (6).

Each A-king beam (10) is connected to and supported by a plurality of columns (14) (supporting means). Each strut (14) extends outward through a through hole (15) formed in the hearth (16) and extends to the lower part of the continuous furnace (1). In the base (17) of the continuous furnace (1), suitable moving and lifting means (20) with the necessary drive means are arranged. The moving/elevating means (20) includes hydraulic cylinders (18) and (19) that, when driven, move the frame (22) running on the wheels (21) in a substantially horizontal direction, and similarly move the frame (22) in the vertical direction. It is equipped with The movement necessary for transporting the aluminum billet (3) is thus imparted to the column (14) which is drivably connected to the moving and lifting means (20). In the illustration of FIG. 1, the aluminum billet (3) is in a lowered position resting on a fixed support beam (8). Pillar (14)
and the walking beam (10) are in the position immediately before the upward movement.

Needless to say, the length of each through hole (15) in the conveyance direction is adapted to the size of the component to be moved in the horizontal direction. In the exemplary embodiment of the continuous furnace of the present invention illustrated herein, the horizontal travel distance, i.e. the aluminum billet (3
) is transported by one actuation of the walking beam (10), the length of each transport distance is approximately 300111 m.

As shown more clearly in Figures 3 and 4, each support (14) of the continuous furnace (1) of the invention has a cover means (25) arranged to seal the hearth (16). It penetrates freely in the vertical direction. Each post (14) is slidably guided in a cover means (25) with a two-way arrow (2
As shown in 7), reciprocating motion is possible in the vertical direction. Each cover means (25) consists essentially of a frame (28), a guide roll (29) for horizontal movement of the cover means attached to the frame (28), and sized insulation material (33) (34). and is preferably made of a steel plate (31). Roughly, the guide roll for raising and lowering the pillar (4
o) is attached to each frame (28), and a column (14)
is in contact with the side of Although in the particular illustrated embodiment of the continuous furnace (1) according to the invention the struts (14) are of square cross-section, the struts (14) are similar to those of the walking beam (1o) and the covering means (25). , Walking Beam (
10) may have any other suitable cross section that can be used in combination with 10).

During the vertical reciprocating movement of the strut (14) indicated by the two-way arrow (27), the strut (14) passes between the strut lifting guide rolls (40) in contact with the strut (14) and through the through hole ( 1
5) is slidably guided through a surrounding enclosure (26). In the exemplary embodiment shown, the enclosure (26) is made of sheet steel, but the enclosure (26) may be made of any material suitable for the purpose. During this vertical reciprocating movement, the cover means (25) maintains a constant height position. Pillar (1
4) is moved substantially horizontally by the moving and lifting means (20) as indicated by the two-way arrow (39);
The cover means (25) is moved in the horizontal direction by the guide roll (40) in contact with the support (14) being pushed by the support (14). The cover means (25) are thus moved forward and in the opposite direction of the transport direction. During the horizontal movement, the guide roll (29) acts as a support member for the covering means (25) and
) runs on a rail (41) that guides it in a substantially horizontal direction as indicated by the two-way arrow (39).

As is clear from FIGS. 3 and 4, the cover means (25) is inserted into the through hole (15) throughout the movement of the support column (14) to the final support position indicated by the dashed line in FIG. The dimensions of the cover means (25) in the conveying direction and in the direction perpendicular thereto are determined so as to protrude toward and cover this. This arrangement ensures that there are no undesirable gaps or voids extending from the interior of the continuous furnace (1) to the exterior. Therefore, during the movement of the support (14) for conveying the material to be heat treated in the continuous furnace (1),
) is maintained in an ideal sealing condition.

The height of the metal box (31) can be adjusted in the vertical direction with respect to the frame (28) of the cover means (25) by means of an adjustment screw (36). Therefore, the metal box (3
1) is movable with respect to the lower surface (23) of the hearth (16) and moves the lower surface (23) of the hearth (16) with a slight contact pressure.
It is also possible to move the object so that it comes into contact with the object. Hearth (
16) It is desirable to provide a suitable metal plate for the floor plate on the lower surface (23).

Insulating materials (33) (34) are included in the metal box (31). Among these heat insulators (33H34), it is desirable to use a replaceable heat-resistant heat insulating board as the upper insulator (33) facing the hearth. The heat insulating plate (33) smoothly contacts the floor metal plate on the lower surface (23) of the continuous furnace (1) and slides along the lower surface of the continuous furnace (1) during movement of the cover means (25). It looks like this.

An angle (42) or similar article holding device is provided on the top surface of the A-King beam (10) to hold the aluminum billet (3) in place. A similar angle can be seen on the fixed support beam (8
) is also provided.

Although preferred embodiments of the invention have been illustrated and described, the invention is not limited thereto, and all other modifications within the scope of the claims may be embodied and practiced. Please understand clearly.

Effects of the Invention According to the continuous furnace for heat treatment of the present invention, the support means is slidably passed through the cover means in the vertical direction and is moved together with the cover means, so that the cover means extends almost completely through the support means. The horizontal movement is adapted to be movable in a substantially horizontal direction, and when the cover means is moved in a substantially horizontal direction by the support means;
The through-holes in the hearth are adapted to be closed by the cover means during the substantially horizontal movement of the cover means, thereby preventing the flow of heat outwardly through said through-holes; Heat loss through this through hole can be prevented. Moreover,
Since the support means is slidably passed through the cover means in the vertical direction, the size of the gap formed between the support means that reciprocates in the vertical direction and the cover means is minimized. Heat loss through is minimal. Therefore, the overall energy requirement of a continuous furnace per 11-ton of the material to be heat treated, such as an aluminum billet 1, which is heat treated in a continuous furnace, is thus significantly reduced, along with the running costs of the heat treatment. Also, the energy and cost savings become more significant as the number of walking beam moving supports increases compared to currently known continuous furnaces.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a vertical cross-sectional view of a continuous furnace for heat treatment taken along a vertical plane parallel to the conveying direction of the material to be heat treated, and FIG. l! A vertical sectional view taken along a vertical plane perpendicular to the conveying direction of J, Figure 3 is the same as ■ in Figure 4.
4 is an enlarged view of the main part of FIG. 1. (1) Continuous furnace for heat treatment, (3) Aluminum billet (metal article to be heat treated), (10)
...A-King beam, (14)... Support column (supporting means), (15)... Through hole, (16)... Hearth. that's all

Claims (9)

[Claims] (1) A walking beam for moving a metal article to be heat treated almost horizontally in a furnace, a supporting means connected to the walking beam so as to be able to move therewith, and a through hole through which the supporting means is passed. a hearth having a hearth and a cover means provided adjacent to the hearth to seal the hearth, the walking beam being substantially horizontal for conveying the metal article to be heat treated by substantially horizontal movement of the support means; The support means is slidably passed through the cover means in the vertical direction and is moved together with the cover means, and the cover means is moved in a substantially horizontal direction by the substantially horizontal movement of the support means. and when the cover means is moved in a substantially horizontal direction by the support means, the through hole in the hearth is blocked by the cover means during the substantially horizontal movement of the cover means. A continuous furnace for heat treatment. (2) The continuous furnace for heat treatment according to claim (1), wherein the hearth has a lower surface, and the cover means is in contact with the lower surface of the hearth. (3) The cover means is equipped with at least one support means lifting guide roll, and the lifting guide roll is brought into contact with the support means adapted to interlock with the cover means. A continuous furnace for heat treatment according to claim (1). (4) The cover means is provided with a guide roll for horizontal movement of the cover means that guides the cover means substantially horizontally when the cover means is moved by the substantially horizontal movement of the support means arranged to interlock with the cover means. A continuous furnace for heat treatment according to claim (1), characterized in that: (5) The continuous furnace for heat treatment according to claim (1), wherein the cover means includes a metal box and a heat insulating material placed in the metal box. (6) The continuous furnace for heat treatment according to claim (5), characterized in that the heat insulating material substantially fills the metal box. (7) The continuous furnace for heat treatment according to claim (1), wherein the cover means is movable vertically with respect to the hearth by an adjustment screw provided thereon. (8) the metal box has a surface facing the hearth;
The continuous furnace for heat treatment according to claim 5, wherein the heat insulating material on the surface of the metal box facing the hearth is made of a heat-resistant heat insulating board. (9) Claim No. 1, characterized in that the heat-resistant heat insulating plate is arranged in a replaceable manner in the metal box.
8) The continuous furnace for heat treatment described in item 8).