JPS58193314A - Heat treatment apparatus - Google Patents

Abstract

PURPOSE:To provide the titled apparatus having a simple and small structure and to evable to carry out heat treatment in high efficiency, by a constitution that a metallic material is heated to a predetermined temp. while moved intermittently and at least two cycles of heat treatments of heating and cooling are applied to the heated metallic material to subsequently cool the same. CONSTITUTION:A metallic material is charged into the basket 50 of a transfer apparatus 5 to be conveyed into the furnace body 2 of a heat treatment apparatus from a charging port 11 having a door 12 and subjected to heat treatment while moved intermittently. At first, said metallic material is heated in a heating zone 4 equipped with a burner 17 and a fan 18 and a preheating zone 3 to raise the temp. thereof to a heat treating temp. and conveyed into a heating and cooling zone 5. In this zone 5, three cycles of heating and cooling treatment are applied to the metallic material by a temp. control means consisting of a radiant tube 19 sending the gas generated by burning fuel and air alternately, and a fan 20. In the next step, the treated metallic material is cooled in a cooling zone 6 consisting of a gradual cooling zone 6a equipped with a burner 21 and a fan 22 and a quenching zone 6b equipped with an air cooling apparatus 27 and the product is conveyed out.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat treatment apparatus that performs heat treatment on steel or other metal materials by alternately heating and cooling a plurality of times.

A heat treatment apparatus shown in FIG. 6 has been devised as a heat treatment apparatus for carrying out the above heat treatment. That is, there are a plurality of heating zones d and 41 and a cooling zone Q inside the furnace.

A device has been devised in which heating zones and cooling zones are arranged alternately, and the metal material is sequentially passed through the heating zone and the cooling zone in the direction indicated by the arrow. With this type of configuration, metal materials can be heat-treated continuously and efficiently, and heat treatment can be performed while the furnace body is filled with metal materials, so the area occupied by the furnace body can be reduced. There is. However, in such a device, temperature control means for heating or cooling are required for each heating zone and cooling zone.
There is a drawback that a very large number of such devices are required, and since s43 must be provided at each inlet and outlet or between the heating zone and the cooling zone, there is also the disadvantage that a large number of such devices are required.

Therefore, the present invention has been designed to eliminate the above-mentioned drawbacks.In addition, heat treatment can be carried out efficiently and the occupied area can be reduced.Furthermore, the temperature control means can be simplified and the number of doors can be reduced. The aim is to provide equipment.

The drawings showing the embodiments of the present application will be described below.

In Figure j1!1, a furnace body 2 is provided on a base frame 1, which is configured to isolate heat from the inside and outside.

Inside the furnace body 2, there are a preheating zone 3, a heating zone 4°, and a heating and cooling zone 5.
, an annealing zone 6a in the cooling zone 6), partition walls 7.8 are provided between them, and each partition wall has a door 9. which can be opened and closed in the vertical direction. 10
It has.

A charging inlet U is formed at one end of the furnace body 2, and an outlet port is formed at the other end, and these doors are provided with doors 12 and 14 that can be opened and closed up and down.

Moreover, inside the furnace body 2, at the bottom, there is a basket ω.
A transfer device is provided that can intermittently transfer the material to the right as shown in the figure. For example, a loaf-hearth is used as the transfer device. The inside of the heating zone 4 is provided with a heated heating means capable of heating the charged metal material.

As the heating means, a burner U and a fan holder which is heated so as to circulate the high temperature gas formed by the burner are used. The heating and cooling zone 5 is provided with temperature control means that can repeatedly heat and cool the metal material charged therein. This temperature control means is composed of a radiant tube and a fan I, for example.

Whether the fugian tube 19 sends high-temperature gas produced by combustion of fuel or only air.
Therefore, the inside of the heating/cooling zone 5 can be heated or cooled. Note that any other arbitrary means can be used as the temperature control means. The inside of the slow cooling zone 6a is heated so that the metal material charged therein can be cooled slowly to a temperature slightly lower than the temperature in the heating zone 4 or the heating/cooling zone 5. Therefore, heating means is provided to maintain the atmosphere at a predetermined temperature of m degrees. As this heating means, a burner and fan 4 are used as in the case of the heating zone. A frame U is provided on the base frame 1 in close proximity to the outlet of the furnace body 20, and a quenching zone 6b in the cooling zone 6 is configured inside the frame U. A discharge port 5 is formed at the end of the frame 24 opposite to the discharge port, and is provided with eight openings K so that it can be opened and closed in the vertical direction. A cooling device is also attached to the frame 24. As this cooling device, an air cooling device I is used, which is capable of cooling the inside of the frame with external air. Next, bring the outlet 25VC close to the above,
A well-known reversal device is provided to enable the basketball team to reverse. On the lower side of the base frame 1, there is provided a feeding device @4 capable of feeding the empty path care force in the direction of the arrow. A lifter is provided adjacent to the charging port H, and a similar lid blade is provided below the frame. The upper surfaces of these lids are provided with a transfer device 34 having a structure equivalent to that of the transfer device described above. Reference numeral is a conveyance device, which conveys the metal material from a previous step (not shown).

In the above configuration, at the loading location in front of the loading port UC1, the lifter first receives an empty basket from the transport device and raises it as shown by the imaginary line. In this state, the metal materials transported by the transport device 36 are thrown into the basket group (the basket indicated by the dashed line). Next, the 8th hole is opened and the metal material is sent into the Passcare) 50Fi preheating zone 3, and the 8th hole is closed. Next, the lifter 31 descends,
Receives an empty pass (see B) from the transport device and raises it. Then, a metal material is thrown into the basket from the conveyor side. Next, the VC door was opened,
The two baskets, basket A sent into the preheating zone 3 and basket 7) H into which the metal material was put, are sent as a set into the heating zone 4, and the door is closed.

The metal materials in these baskets are then heated in the heating zone 4. During the heating process, metal materials are placed into the next two baskets A' and B' in the same manner as described above. Next, when the heating of the metal materials in the two baskets is completed in the heating zone 4, the door 9 is opened and the two groups of baskets indicated by B are assembled into the heating and cooling zone S. sent. In this case, the two bus keratoms ' and B', to which the metal material has been charged, are sent into the heating zone 4 in the same manner as described above. Thereafter, in the same manner, a large number of baskets, each consisting of two baskets, are transported inside the furnace body 2 for use. And from the outlet port of the furnace body 2,! A with Vc in the state where sM is open,
Two baskets indicated by B are sent toward the quenching zone 6b. In the rapid cooling zone 6b, the metal material inside the basket is air-cooled! It is cooled by fi27. Once the cooling is finished! J126 is opened and the output port is opened, so that the basket group indicated by M is first sent into the reversing device T. Then, in the reversing device 128, the basket is reversed, and the metal material inside is sent out to the next stage. When the reversing device returns to its original position, the nine baskets become empty and the nine baskets stand on top of the futa field in a rising state. Thereafter, the lifter ring descends and the empty basket is sent to the transport device 29. Thereafter, with the lifter 1 raised again, the bus get (toward) indicated by B is sent to the reversing fM station 11, and the metal material is delivered in the same manner as in the previous case. Then, the empty basket ω, indicated by B, is sent to the transport device 4 via the same INK lifter ring as in the above case.

Next, an example of the heat treatment mode of the metal material in the process K in which the basket group circulates as described above will be explained based on FIG. 2. First, metal materials loaded into a basket (also simply referred to as Basquera A) indicated by M at a loading location are heated from room temperature to about 250'O in a preheating zone 3. Next, the metal material newly loaded into the basket (also simply referred to as Baskera B), indicated by metal material B in the Baskeratom, is fed into a heating zone and heated to about 700°C. That is, the metal material in the basket B is heated from 250°C to 700°C, and the metal material in the basket B is heated from room temperature to 700°C.

Next, when those baskets are sent to the heating and cooling zone 5, the metal materials in those baskets are first heated from 700°C to a temperature exceeding the temperature of the Mu1 inflection point, for example, 750'O4, and then It is cooled to a temperature lower than the above-mentioned transformation point, for example, yoo'ct. Thereafter, when those baskets are transferred to the next position in the heating and cooling zone 5, the metal materials in those baskets are heated to a temperature exceeding the above-mentioned point U again, for example, 745°C.
It was heated to 11, and then it changed again to 1m point! It is cooled down to a low temperature of 700°C. In this heating and cooling process, the metal materials in the two baskets newly fed into the heating and cooling zone 5 are heated to 75 Q'C at the same time as the above heating, and at 700'C1. Cooling is performed simultaneously with the above cooling. After that, when the two baskets are transferred to the next position in the heating and cooling zone 5, the metal materials inside them are heated there for a third time to a temperature that exceeds the temperature of the inflection U point, for example, 7400 C, and then undergoes transformation. The stone is cooled to a temperature of 700'0, which is lower than the point temperature.

The metal materials in those baskets are then fed into an annealing zone 6&, where they are gradually cooled to sso'c. Then, it is cooled down to room temperature in the rapid cooling zone 6b.

Figure 3 shows how the temperature of the metal material changes during the heat treatment process as described above. That is, the metal material in Vaskeratome changes in temperature as shown by the solid line KfA, and the metal material in Vaskeratome B changes in temperature as shown by the broken line.

Next, FIG. 4 shows a different aspect of the heat treatment. In the embodiment shown in FIG. 4, both the metal material in the basket B and the metal material in the basket B are heated in the heating zone at a temperature exceeding the M1 transformation point, for example, 75 G'Of. Next, when they are sent to the heating and cooling zone,
First, they are heated to temperatures lower than the transformation point, e.g. 700
It is cooled to a temperature of 745°C, then transformed again and heated to a temperature above the mastication temperature, for example 745°C. Then, when they are transferred to the next position lf in the heating and cooling zone, those metal materials are cooled again and then heated.

Next, those metal materials are sent to an annealing zone where 650＠
It is gradually cooled down to C. Thereafter, it is cooled to room temperature in the same manner as in the case described above.

Next, FIG. 15 shows the process of temperature change of the metal material when the metal material is heated in the manner shown in FIG. 4. That is, the temperature of the metal material in the basket B changes as shown by the solid line, and the temperature change of the metal material in the basket B changes as shown by the broken line.

As described above, in this invention, since the metal material can be heated and cooled during the process of moving it in one direction by the transfer device, it has the effect of making the continuous heat treatment of the metal material more efficient. Of course, the above heat treatment can be performed with the heating zone, heating/cooling zone, and cooling zone filled with metal material, so it has the advantage of being able to perform heat treatment without dead space. be. This is useful in that it can meet the demand for reducing the heating power while occupying an area of the furnace.

Furthermore, even if there is a single KFJJ heating and cooling zone, the transfer speed of the metal material in that heating and cooling zone is equivalent to a temperature change of 1/I/ (or more), assuming that "heating and cooling" is 10 + 1. For example, heat treatment is performed to improve the quality of the metal material by repeatedly applying a heating action that causes the temperature to exceed the transformation point and a cooling action that lowers the transformation temperature (a) to the metal material. It has the feature of being able to.

Furthermore, even if the quality of the metal material being transferred can be improved by the multiple cycles described above, the heating and cooling zone may have a single structure, so the temperature control means within the room can be unified. There are structural advantages and further structural benefits such as fewer entrance and exit doors for the heating and cooling zone.

[Brief explanation of drawings]

The drawings show an embodiment of the present application, and FIG. 1 is a longitudinal cross-sectional view;
Figure 2 is a time chart showing an example of the heat treatment process;
The figure is a graph showing how the temperature changes in metal materials, Figure 4 is a time chart showing different types of heat treatment, and Figure 5 is a graph showing how the temperature changes in metal materials.
FIG. 6 is a graph showing the temperature change of the metal material in the heat treatment mode shown in the figure, and FIG. 6 is a diagram schematically showing a conventional heat treatment apparatus. 5... Heating and cooling zone, 4... Heating zone, 6... Cooling zone, Takumi... Transfer device, ■... Basket. Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] A heating and cooling zone is provided with a temperature control means that can repeatedly perform heating and cooling, and a heating and cooling zone is provided in front of the heating and cooling zone in a tangential arrangement for feeding the charged metal material into the heating and cooling zone. A heating zone heated to raise the temperature to a suitable temperature, and a cooling device disposed adjacent to the rear of the heating/cooling zone to cool the metal material being carried out from the heating/cooling zone before being sent to the next stage. The metal material can be charged into the heating zone, and after passing through the three zones, the metal material can be carried out from the cooling zone to the next stage. A transfer device is attached, and furthermore, the transfer device transfers the metal material between the two! 1K movable KWk, and the transfer speed is set within the range of heating and cooling the metal material passing through the heating and cooling zone as one cycle, and the cycle is repeated at least twice. A heat treatment device characterized by nine things.