JPH02143086A - Continuous heat treatment furnace - Google Patents

Abstract

PURPOSE:To reduce the quiescent time of the title furnace remarkably by a method wherein the title furnace is provided with a gate type beam, elevating preceeding heat treated materials from rolls to avoid and permitting the advance of successive heat treated materials, a guide elevating the beam and an elevating means. CONSTITUTION:A continuous heat treating furnace is provided with transfer rolls 2, burners 4, a gate type beam 6, elevating heat treated materials from the rolls 2 and established between the rolls 2, a link mechanism 3, elevating the beam 6, and a guide 10, guiding the elevation of the beam 6. When a preceeding material 7 necessitates the heat treatment of a long period of time, the mechanism 3 is extended to elevate the beam 6 to the upper part of the rolls 2, avoid the material 7 from successive heat treated material 8 and effect a predetermined heat treatment while the successive material 8, not necessitating the heat treatment of a long period of time, is transferred by the rolls during a period in which the preceeding material 7 is being elevated whereby the heat treatment of the successive material 8 may be finished earlier than the same of the preceeding material 7. According to this method, the quiescent time of the furnace may be reduced remarkably longer than the same so far and, therefore, the productivity of the furnace may be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to a continuous heat treatment furnace, and more specifically, a continuous heat treatment method in which the order of heat treatment of materials to be heat treated that are continuously charged can be changed in the furnace. Regarding furnaces.

[Conventional technology]

Continuous heat treatment techniques for materials to be heat treated are disclosed, for example, in JP-A-61-252483 and JP-A-62-112717.

JP-A No. 61-2:12483 calculates the conveyance speed that satisfies the heat treatment conditions for the succeeding material, and determines the separation distance between the preceding material and the succeeding material from the magnitude relationship between this conveying speed and the conveying speed of the preceding material. The timing for changing the conveyance speed is determined, the following material is loaded at the determined separation distance, and the conveyance speed is changed at the determined timing, even if the conveyance speeds of the preceding material and the following material are different. , it is possible to charge and heat-treat the trailing material without waiting for the extraction of the trailing material to be completed, and to improve the so-called cover ratio, which minimizes the empty furnace time to the necessary minimum.

Also.

JP-A-62-1.12717 discloses a method in which a plurality of conveying elements are arranged in parallel, and each conveying element is capable of conveying the heat-treated material at different speeds, thereby improving the efficiency of heat treatment. be.

[Problem to be Solved by the Invention 1] Regarding the above-mentioned prior art, ■Japanese Patent Application Laid-Open No. 61-252483 requires complicated software for various calculations, and also requires the installation of heat-treated materials to reduce the empty furnace time. Advance rQ selection of entry order must be considered. In addition, there is a problem that it is impossible to eliminate the necessary minimum empty furnace time, and the effect is small. In addition, JP-A No. 62-1.12717 has the disadvantage that equipment costs are high because multiple conveying elements are installed in parallel. There is a problem in that it is difficult to put it into practical use because it needs to be expanded to about twice the current width.

The present invention has been proposed to solve these problems, and has low equipment costs and eliminates the need for advance preparations such as the order in which heat-treated materials are passed through and the sorting of heat-treated materials by cross section. It is an object of the present invention to provide a continuous heat treatment furnace that improves the cover ratio.

[Means for Solving the Problems] The present invention solves the above-mentioned problems, and is applied to a continuous heat treatment furnace in which a material to be heat treated is continuously conveyed by a conveyor roll, and the material to be heat treated is heat treated during the conveyance process. Therefore, the following technical measures were taken. Namely, (1) a gate-shaped beam that is erected between the rolls of the transport rolls and lifts and retreats the preceding material to be heat-treated from the rolls and allows the subsequent material to be heat-treated to advance; (2) a lifting means for raising and lowering the beam; (2) A guide is provided for guiding the beam to move up and down.

[Function j] Since the continuous heat treatment furnace of the present invention was purchased as described above, the material to be heat treated that requires long-term heat treatment is evacuated from above the conveyor roll by the portal beam and subjected to the prescribed heat treatment. In addition, it is possible to transport the succeeding material, which does not require long heat treatment, by means of transport rolls, and to complete the heat treatment faster than the preceding material. That is, the empty furnace time can be significantly reduced compared to the conventional method.

[Example J An explanatory diagram of an embodiment of the present invention is shown in FIGS. 1 and 2. FIG. 1 is a cross-sectional view in the longitudinal direction, and FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1.

The continuous heat treatment furnace of the present invention has a charging door 1. Conveyance roll 2.
A portal beam 6 for lifting the material to be heat treated from the transport rolls 2 is installed between the transport rolls 2 in a normal furnace body 5 consisting of a burner (or radiant tube) 4, an extraction door 9, etc.
A link mechanism 3 for raising and lowering the beam 6 and a guide 10 for guiding the raising and lowering of the beam 6 are provided.

Therefore, when the preceding material 7 requires long-term heat treatment, the link mechanism 3 is extended by the motor II, the beam 6 is lifted above the conveyor roll 2, the preceding material 7 is evacuated, and a predetermined heat treatment is performed. The succeeding material 8, which does not require long-term heat treatment, is conveyed by the conveying rolls 2, and the heat treatment can be completed faster than the preceding material 7. When the beam 6 is not in use, the upper surface of the beam 6 is stored below the pass line of the transport roll 2 by the link [43].

In the embodiment of the present invention, the link machine 1 is used as the lifting means for the beam 6.
1113 was used, but the elevating means may be of any type as long as it allows for elevating and lowering strokes, and may be a ski knee, hydraulic cylinder, pneumatic cylinder, or the like.

Although the beam 6 is made of heat-resistant steel, it may also be made of steel whose surface is protected with a refractory or whose inner surface has a water-cooled structure.

Further, although one drawing shows one set of the gate Jf double beam, lifting device, and guide, it goes without saying that it is possible to provide multiple sets of devices depending on the heat treatment conditions of the material to be heat treated.

[Effect of the invention] The present invention has the following excellent effects.

■As the subsequent heat-treated material, which can be heat-treated in a short time, can overtake the preceding heat-treated material, which requires long-term heat treatment, it is possible to improve the cover ratio from 40 to 50% to 60 to 70%. This makes it possible to improve productivity.

■It eliminates the need for preparations such as the order of passing the heat-treated materials and the sorting of the heat-treated materials by cross-section.

(■Equipment costs are low and control is easy.

■Due to processing capacity, the furnace length of thick plate heat treatment furnaces is extremely long <1.
However, by implementing the present invention, it is possible to shorten the furnace length by approximately 20%.

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams of one embodiment of the present invention, in which FIG. 1 is a longitudinal sectional view, and FIG. 2 is an A-A in FIG. 1.
FIG. ■...Charging door 2...-Roll 3...Link mechanism 4-...Burner 5...Furnace body
6...Beam 7--Previous material 8--Following material 9...Extraction door 10...Guide 11-
··motor

Claims (1)

[Scope of Claims] 1. In a continuous heat treatment furnace in which a material to be heat treated is continuously transported by transport rolls and the material to be heat treated is heat-treated during the transport process, a furnace is installed between the rolls of the transport rolls to heat the material to be heat treated in advance. A continuous heat treatment furnace characterized by comprising a portal beam that is lifted and retracted from the roll to allow the subsequent material to be heat treated to advance, a lifting means for raising and lowering the beam, and a guide for guiding the raising and lowering of the beam. .