JPH0324224A - Heating method and heating device for steel products - Google Patents

Abstract

PURPOSE:To heat steel products to an optimum temp. without requiring the space parts between steel kinds by heating the steel products of different hot working temps. up to a common temp. in a heating furnace, then heating the steel products up to the temp. meeting the kinds of the steel products in an induction heating furnace. CONSTITUTION:Two or more kinds of the steel products 1 which vary in heating temp. are heated up to the temp. common to the respective steel products 1. The induction beating furnace 3 is provided adjacently to the heating furnace 2 and a tracking system 5 is provided in an outlet 25 of the heating furnace 2. The steel kind of the material to be heated next is discriminated by a computer of the tracking system 5 and the heating temp. is set. The output of the induction heating coil is regulated to heat the steel products to the temp. meeting the kind thereof in the induction heating furnace 3 in accordance with this information 6. The temp. in the heating furnace 2 is measured by a thermometer installed in the inlet of the heating furnace 2 and thereafter, the output of the induction heating coil is adjusted by calculating the temp. at which the steel products are heated up in the induction heating furnace 3.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention... Spring steel. Two or more steel materials with different hot working temperatures, such as carbon steel and stainless steel, can be heated efficiently. Regarding heating methods and heating devices. [Conventional technology] Conventional. Hot working of steel materials involves heating the steel material to the working temperature (for example, 1000"C) in a heating furnace using high-temperature gas. Then hot working B.
: Performing hot processing such as rolling.

but. When hot working different types of steel materials in small quantities,
There is the following problem. for example. Spring steel at 900°C, carbon steel at 1000°C
First, stainless steel is heated to 1200'C and rolled. Therefore. It is not possible to continuously heat these dissimilar steel materials to -.degrees in a heating furnace. Therefore. As shown in FIG. 9, the heating furnace 9 includes a low temperature heating zone (preheating zone) D, a medium temperature heating zone (heating zone) D, and a high temperature heating zone (D).
A soaking zone) F is provided, and a dummy material 8 is placed between the different steel materials. A heating method is used. That is, as shown in FIG. 9, the rope l is successively pushed into the heating furnace 9 by the pusher 91. The above-mentioned steel material 1 is made up of three pieces of stainless steel 13, for example, as one block. Also, three pieces of carbon w412 are made into one block. Similarly. The four pieces of spring steel 13 are made into one block and are sequentially pushed into the heating furnace 9 using the busher 91. Then, a piece of material 8 is inserted between each of these blocks. Also. On the contrary, the heating temperature is relatively low. For example, after heating carbon steel 12. The temperature can also be set so that stainless steel 13, which has a higher heating temperature, is heated.

Also, the above pusher 9l is not used. For example, in a walking beam furnace, instead of inserting the dummy material 8, a method of providing a constant rBl distance between steel types is adopted.

Next, the steel material 1 is... In the low temperature heating area D in the heating furnace 9. For example, it is heated up to 300'C, and in the medium temperature heating region E, it is heated up to, for example, 500'C. Then, in the high temperature heating region F, the stainless steel fJA13 is heated to a target temperature of 1200°C. During this time. The carbon steel 12 waits while being heated in the medium temperature heating area E. Therefore, the carbon steel material 12 (processing temperature 1
000"C) is not affected by the heating temperature of the high temperature heating area F (1200"C for stainless steel). The reason is that the stainless steel wire 12 in the high temperature heating area F,
This is because the dummy material 8 is interposed between the carbon steel work 2 and the carbon steel work 2 that will be heated next. Also. This is because in a walking beam furnace, a certain distance is left between ill seeds.

After the stainless steel 813 is transferred from the heating furnace 9 to the processing process. The heating temperature in the high-temperature heating zone F is lowered, and the carbon steel 12 that has been moved to the high-temperature heating zone F is heated to 1000°C. Hereafter, the steel is heated in this manner to the processing temperature appropriate for the steel type. This makes it possible to heat dissimilar steel materials without being affected by different heating temperatures. In addition. In Figure 9. Reference numeral 92 is a skid, and 93 is a heating device. [Problem to be solved] However, the above conventional method has the following problems. That is. It is necessary to place a dummy material 8 between different types of steel to avoid the influence of the heating temperature of other types of steel.

Furthermore, in a walking beam furnace, it is necessary to leave a certain distance between the steel types in the furnace, and this creates a time period during which no steel is sent to the processing process, reducing productivity.

Furthermore, it is necessary to adjust the temperature by raising or lowering the temperature within the high-temperature heating area E for each different steel type. For example, to heat stainless steel 13, raise the temperature to 1200°C. When heating the spring steel 11 after that, it is necessary to lower the temperature to 900''C.

Therefore, it becomes difficult to adjust the heating temperature, and the target temperature may not be reached. Also. Heating may take a long time.

The present invention has been made in view of such conventional problems, and provides a method and method for heating steel material, which does not require a dummy material or a space between the steel types, and which can heat the steel material at an optimal temperature. The aim is to provide a heating device. [Means for solving the problem] The present application provides the inventions of the first and second claims relating to a method for heating steel materials. The third aspect of the present invention relates to a heating device for sea bream material.

The invention of the first claim is such that two or more steel materials having different hot working temperatures are sequentially heated in a heating furnace, then the steel materials are heated to a target working temperature in an induction heating furnace, and then the steel materials are sent out to the working process. In the heating method, the steel material is heated in the heating furnace to a heating temperature common to the above steel materials.
Next, there is a method for heating steel materials, which is characterized by induction heating in an induction heating furnace to a processing temperature that corresponds to the type of steel material. In the invention of claim 1. The above hot working temperature is w
4 The heating temperature required prior to processing depending on the type of material. For example, spring steel has a temperature of around 900°C, carbon steel has a temperature of around 1000°C, and stainless steel has a temperature of 120°C.
The temperature is around 'C. Furthermore, the above-mentioned common heating temperature refers to the temperature of the high temperature portion common to two or more types of steel materials that are heated together in the heating furnace. For example, the above spring steel and carbon steel. When three types of stainless steel are heated together in a heating furnace. As a heating temperature common to these heating temperatures
Select 800-900℃. Further, the above-mentioned heating furnace has a low temperature heating region of, for example, room temperature to 300'C. Medium temperature heating region of 300-600°C. It consists of a high temperature heating region of 600 to 900°C. The heating furnace also includes a skid and a heating device for heating the steel material while conveying it. Also, as the heating furnace. Instead of the above skid, there are models with a walking beam or walking hearth installed inside. Also. The above induction heating furnace is. The heat generated by high-frequency or low-frequency induced currents causes the above-mentioned sinus material to be damaged. This is a furnace that performs induction heating to the desired heating temperature. In addition, as for the above processing process. For example, hot rolling. Forging processing, etc. In addition, the invention of claim 2 is the invention of claim 1, in which the temperature of each steel material is measured at the entrance of the induction heating furnace and the temperature to be raised is calculated in advance for each steel material. It uses induction heating to a processing temperature suitable for. The invention of claim 3 provides a heating furnace for heating two or more steel materials having different hot working temperatures to a common heating temperature.
It consists of an induction heating furnace that heats the steel material to a processing temperature depending on the type of steel material, a tracking system that determines the type of steel material sent to the induction heating furnace, and a temperature measurement system installed at the entrance of the induction furnace. This is a unique heating device.

In the invention of claim 3. The above-mentioned tracking system is a device that determines the type of J181 material and, based on that information, sends a command as to how many times the steel material should be heated in the induction heating furnace.

Additionally, by determining the order of processing in advance, the computer can track the steel material and set the heating conditions for the induction heating furnace based on the order of processing. Also, due to the temperature measurement system. Measure the temperature in the heating furnace. Next. The heating conditions for the induction heating furnace can be set by calculating in advance the temperature at which the induction heating furnace is used. [Function] In the invention of the first claim, the steel materials to be heated are sequentially fed into the heating furnace regardless of the steel type.
and. In the heating furnace. Heat to a temperature common to each steel material. Next, the steel material thus heated to a common temperature (for example, 800° C.) is sent to an induction heating furnace depending on the preparation status for the hot working step. The steel is then heated in the induction heating furnace to the desired processing temperature for each steel type. The steel material heated in this way is then sent to the next process, the processing process. Moreover, in the invention of the second claim, heating is performed in an induction heating furnace at a processing temperature required for each individual steel material, rather than depending on the heating degree depending on the steel type as in the invention of the first claim. In the invention of claim 3, first, the outlet of the heating furnace (
In some cases, this is the part corresponding to the entrance of an induction heating furnace.The steel material is classified as Class II by using the above-mentioned tracking system. Based on this information, a command is sent to the induction heating furnace to heat the steel material to the required processing temperature. In other words, a command is sent to the induction heating furnace to heat the steel material to the required processing temperature in a predetermined order based on computer tracking. In induction heating furnaces. Based on the above command, the output is adjusted and the steel material is heated by induction.Also, the temperature is measured using a temperature system set at the entrance of the induction heating furnace, the temperature to be raised is calculated, and a command is sent to the induction heating furnace. [Effect] As above. According to the invention of the first claim, in the heating furnace. Regardless of the type of steel material, it is heated at a heating temperature that is common to each steel material.

Therefore, as before. There is no need to insert dummy materials between each steel block. Also. There is no need to leave spaces between each steel block. Furthermore, even if the steel type changes, the temperature can be raised to the desired processing temperature. There is no need to lower the temperature.

In addition, since the steel material is heated to a common heating temperature in the heating furnace, it can be heated to the desired processing temperature in a short time in the induction heating furnace. In addition, since it is heated to the processing temperature in a short time by induction heating,
It also has the effect of making it difficult for decarburization to occur even in carbon-rich steel materials. Further, according to the invention of the second claim, even if the steel materials are of the same type, and even if the heating temperature of the steel materials in the heating furnace varies, it is possible to heat the steel materials to a processing temperature appropriate for the processing method of the steel materials. can. Further, the same effects as in the first claim can be obtained.

Moreover, according to the invention of claim 3, in addition to the effects of claim 1 above. The tracking system determines the steel type. In other words, by computer-based tracking, it is possible to issue a command to the induction heating device to produce the desired heating output.

Therefore. Even if you feed any steel material into the heating furnace, regardless of the steel type, in an induction heating furnace. It can be automatically heated to the processing temperature appropriate for the steel type or material and sent to the processing process. In other words, heating management can be performed automatically. [Example] Regarding the heating method and heating device for steel materials according to the example of the present invention. This will be explained using FIGS. 1 to 8.

That is, in the heating method of this example, as shown in Fig. 1, two or more steel materials l having different hot working temperatures are heated in a heating furnace, then heated to the target working temperature in an induction heating furnace 3, Next, it is sent to a processing device (not shown). The steel material 1 is made of three types: spring steel 11, carbon fIAl2, and stainless steel 13. Also. The above hot heating temperature is around 900°C for spring steel 11. Around 1000'C for carbon steel l2, 12 for stainless steel l3
It is around 00°C.

The heating furnace 2 has a low temperature heating area A that heats from room temperature to 300°C, a medium temperature heating area B that heats from 300 to 600°C, and a high temperature heating area C that heats from 600 to 800°C. It becomes more. The final temperature of this high temperature region C is 800°C. This heating temperature is common to the above three types of steel materials.

Further, the heating furnace 2 has a busher 21 and a roller 211 at the inlet for feeding the steel material.

Also. The heating furnace 2 is. It has a skid 22 and a heating device 23 for conveying and heating the steel material 1 fed by the puncher 21. In addition, the heating furnace 2 is provided with a heat sink as shown in Fig. 2. An induction heating furnace 3 is arranged adjacently.

In addition, a plurality of induction heating furnaces 3 are installed. The final terminal group is arranged adjacent to the rolling device 4. In the induction heating furnace 3. As shown in FIGS. 3 and 4, a cylindrical induction heating coil 31 is provided. Furthermore, V rollers 30 are provided at the inlet section 32 and outlet section 33 of the induction heating furnace 3, respectively. Moreover, the V roller 30 is. As shown in FIG. 5, precautions are taken so that the steel material 1 can be transported while being supported in the groove 301.

As shown in FIG. 6, the outlet 25 of the heating furnace 2
A tracking system 5 is installed. Also. By the computer of the tracking system 5. Next, determine the mesh type of the material to be heated.

Then, the heating temperature is set according to instructions from the computer. Next. In the induction heating furnace 3, the output of the induction heating coil 31 is adjusted based on the information 6 from the tracking system 5 so as to perform induction heating to a heating temperature according to the type of steel material.

In addition, the temperature inside the heating furnace 2 is measured with a thermometer installed at the entrance of the induction heating furnace 2, and then the temperature to be raised in the induction heating furnace 3 is calculated to adjust the output of the induction heating coil. Next, we will explain the effects. In the heating method of this example, first, the steel material l is heated in the heating furnace 2 to a temperature common to all steel materials, and then sent to the induction heating furnace 3. Here, it is heated to the desired heating temperature.

That is, in the heating furnace 2. As shown in Fig. 1, spring steel 11, carbon steel 12. Heat to a heating temperature common to stainless steel 13 (800°C).

Next, as shown in FIG. 6, at the outlet 25 of the heating furnace 2, the steel type is determined by the tracking system 5.

and. When the steel material discharged from the heating furnace 2 is determined to be, for example, spring steel, the trasoking system 5 sets the processing temperature to 90°C, which is the processing temperature of the spring steel l1 of the induction heating furnace 3.
Issue a command to output heating output up to 0°C. This means that the above carbon! 1 2. The same applies to stainless steel 13. Therefore. The material can be heated to the processing temperature corresponding to mn in a short time. In other words, as shown in Fig. 7, the temperature P (
800'C), the heating temperature Q(900'C) of spring Ill is
up to (around C). Heating temperature R of carbon steel 13 (1000°C
before and after). Heating temperature S of stainless steel w413 (120
(around 0℃). The temperature can be raised within a short time of XY and Z, respectively. on the other hand. It is also possible to set the heating time of the steel materials in the induction heating furnace to the same time to raise the temperature to the target temperature.

That is. As shown in Figure 8 <. Temperature P common to AI materials
(800°C), heating temperature Q of spring steel 11 (around 900°C), heating temperature of carbon steel 12 (around 1000"C)
, Heating temperature S of stainless steel l3 (around 1200°C)
Until. All the temperatures are raised in 40 seconds, for example. When using this method, the amount of electricity input to the induction heating furnace is changed depending on the heating temperature. In addition, temperature variations in the heating furnace 2 were measured using a temperature measurement system installed at the inlet of the induction heating furnace 30.
Calculate the heating temperature. It is also possible to raise the temperature of each Iil material to a predetermined temperature. This makes it possible to reduce variations in temperature rise.

Note that in this example, no dummy material is required, so
There is no need to leave gaps between steel members.

In addition, in 1 induction heating furnace 3. It is possible to raise the temperature to the optimum processing temperature for each steel material. In the heating furnace 2, the material is heated to a temperature lower than the processing temperature. Therefore, in the case of carbon lynch R1 material, for example the spring steel 11 mentioned above. It is possible to prevent decarburization of steel materials. Furthermore, since there is no gap between the five steel materials, productivity can be improved.

Furthermore, since the heating device of this example has a computer-controlled tracking system 5. Regardless of the type of steel in the heating furnace 2. Even if you supply steel material arbitrarily. Heating can be automatically performed in the induction heating furnace 3 according to the type of steel.

[Brief explanation of drawings]

Figures 1 to 7 show a heating method and heating device for steel materials according to an embodiment of the present invention, and Figure 1 is a side view of the heating furnace, and Figure 2 is a side view of the heating furnace.
The figure is a plan view of the entire heating equipment, Figure 3 is a perspective view of the induction heating furnace, Figure 4 is a front view of the induction heating furnace, Figure 5 is a front view of the steel material on the V roller, and Figure 6 is the heating equipment. An explanatory diagram. FIGS. 7 and 8 are graphs showing the relationship between heating temperature and required time for temperature increase (Hr), and FIG. 9 is a side view of a conventional heating furnace. l ・ ・ ・ l 1 ・ ・ ・ 1 2 ・ ・ ・ l 3 ・ ・ ・ 2 ・ ・ ・ 3 ・ ・ ・ 3 1. ．． ．． 4 ・ ・ ・ 5 ・ ・ ・ Spring steel, carbon steel, stainless steel heating furnace induction heating furnace induction heating coil rolling processing equipment, Tora 7 King system,

Claims (3)

[Claims] (1) A method of heating two or more steel materials having different hot working temperatures in a heating furnace, then heating the steel materials to a target processing temperature in an induction heating furnace, and then sending the steel materials to the processing step, , A method for heating steel materials, characterized in that in the heating furnace, the steel materials are heated to a heating temperature common to the above steel materials, and then in the induction heating furnace, the steel materials are induction heated to a processing temperature according to the type of the steel materials. (2) A method of heating two or more steel materials having different hot working temperatures in a heating furnace, then heating the steel materials to a target processing temperature in an induction heating furnace, and then sending the steel materials to a processing step, In the heating furnace, the steel material is heated to a heating temperature common to the steel materials, the temperature is measured for each steel material at the entrance of the induction heating furnace, and the temperature to be raised in the induction heating furnace is calculated in advance, A method for heating steel materials, characterized in that each steel material is induction heated to a processing temperature corresponding to the steel material. (3) A heating furnace that heats two or more steel materials with different hot working temperatures to a common heating temperature, an induction heating furnace that heats the steel materials to a processing temperature depending on the type of steel materials, and a heating furnace that heats two or more steel materials with different hot working temperatures to a common heating temperature. A heating device comprising: a tracking system for determining the type of steel material being heated; and a temperature measurement system installed at the entrance of an induction heating furnace.