JPS6086789A - Meating or warming method of heat treating device or like - 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 The present invention provides a method for efficiently heating or insulating parts of heat treatment equipment used in the chemical industry, food industry, machinery industry, polymer industry, textile industry, packaging industry, etc. at a uniform temperature. It relates to a method of heating or keeping warm.

For example, electric heaters, water vapor, oil, molten salts, etc. are used to heat or keep warm injection molding machines, molds, extruders, various molding guides, heat rolls, melt spinning baths, etc. commonly used in the polymer industry. Jacket heating using a heating medium, electromagnetic induction heating, and methods using heat rays such as infrared rays are used.

Since the above-mentioned electric heater usually uses a power source of 100V or more, sufficient insulation treatment is required for itself and its surroundings to prevent electrical leakage and for safety measures, and the area occupied by the heating wire is Because it is extremely small compared to the area of the object to be heated, it is necessary to locally heat it to a high temperature in order to supply sufficient heat, resulting in temperature differences and thermal distortion depending on the location, and furthermore, it may cause damage to objects other than the target object. There is a lot of heat loss due to heat transfer and radiation, and measures to prevent burns are necessary.

Further, the method using a heat medium requires the installation of a jacket, etc., and a heating and circulation device for the heat medium, and a large amount of heat medium must be circulated in order to make the temperature uniform.

Furthermore, electromagnetic induction heating requires an induction coil, and there are restrictions on the shape and material of the heated object.

Furthermore, heating using heat rays such as infrared rays requires a heat ray generator and a space that uniformly receives the heat rays.

The present invention solves the problems of conventional heating or heat retention methods as described above;
That is, it is a method for uniformly heating or keeping warm a heating part or a heat-retaining part of a heat treatment device, etc., in which a plate-shaped heating element that can be shaped into any shape is interposed in the heating part or heat-retaining part, and a heat-resistant insulating material is interposed therebetween. A heat treatment apparatus, etc., characterized in that the plate-shaped heating element is coated and fixed with a heat-resistant adhesive, and a commercial frequency AC or DC voltage of 70 V or less is applied to the plate-shaped heating element to generate heat. This provides a method for heating or keeping warm.

Hereinafter, the method for heating or keeping warm using the heat treatment apparatus, etc. of the present invention will be described.
A preferred embodiment thereof will be described.

In the present invention, as the heating element, a plate-shaped heating element which can have any arbitrary shape is used. Such plate-shaped heating elements include iron,
2. Metals such as Kel, chromium, titanium, 3. Aluminum, alloys thereof, and one or more conductive materials such as graphite and carbon fiber are used as plates, foils, perforated plates, wire mesh, and punched wire mesh. In addition, heat-resistant insulating materials include inorganic materials such as mica, asbestos, marble, and sulfur, and porcelain materials such as insulators, insulators, steatite, and glass ceramics. , glass materials such as quartz glass, soda glass, lead glass and their fibers, inorganic heat-resistant fibers such as high silicate fibers, ceramic fibers, alumina fibers, and mullite fibers, wood, natural fiber spinning such as cotton yarn, polyolefin, polystyrene , polyvinyl chloride, polyester, nylon, Teflon, polyurethane, polyimide, polyamideimide, polysulfone, and other film-like, fibrous, and molded synthetic resin materials; and rubbers such as natural rubber, ebonite, butyl rubber, chloroprene, and silicone rubber. These materials are used alone or in combination depending on the location and purpose of use, the shape of the object to be heated, and the required heat resistance.

In addition, heat-resistant adhesives include epoxy resin, silicone resin, formal resin, polyimide, polyimide amide, phenoxy resin, polysulfone, etc., dissolved in a solvent, organic titanium adhesive, heat-resistant festival, and heat-resistant cement. , glass adhesives, inorganic adhesives such as aluminum phosphate and sodium silicate, and coating agents, and these are determined depending on the location and purpose of use, the shape of the object to be heated, the required heat resistance, and even Use either alone or in combination depending on the heat-resistant insulating material used.

Therefore, when carrying out the heating or heat retention method of the heat treatment apparatus, etc. of the present invention, first, the above-mentioned plate-shaped heating element, which can be shaped into any shape, is placed in the heating part or heat retention part of the heat treatment apparatus, etc. Covering and fixing is performed with the heat-resistant adhesive with the heat-resistant insulating material interposed therebetween. In the field of polymer industry, for example, heat treatment equipment for covering and fixing plate-shaped heating elements include:
Injection molding machines, molds, extruders, various molding dies, heat rolls, melt spinning baths, etc., as well as various heat treatments used in the chemical industry, food industry, machinery industry, textile industry, packaging industry, etc. device or a heat-retaining device. Although there are no restrictions on how to cover and fix the plate-shaped heating element, it is preferable to uniformly cover and fix the plate-shaped heating element to a location that requires heating or heat retention, that is, a heating portion or a retaining portion (heated body). Furthermore, when covering and fixing the plate-shaped heating element, the plate-shaped heating element is generally bent to correspond to the shape of the heating section or the heat-retaining section.

In addition, when fixing the plate-shaped heating element to the heating part or heat retention part,
If you use a holding plate together with a heat-resistant adhesive and the holding plate is a conductor, use the holding plate as described above! A heat-resistant insulating material may be interposed between the body and the body, and these may be bonded together with a heat-resistant adhesive if necessary.

Further, from the viewpoint of safety measures, it is preferable to cover and fix a heat-resistant insulating material with a heat-resistant adhesive on the surface of the plate-shaped heating element opposite to the heating section or the heat-retaining section.

Next, a commercial frequency alternating current or direct current voltage of 70 V or less is applied to the plate-shaped heating element coated and fixed as described above to cause the plate-shaped heating element to generate heat. This heat generation uniformly heats or keeps the heating section or the heat retaining section at a desired temperature. The reason why the voltage applied to the plate-shaped heating element is set to 70V or less in the present invention is that, according to the present invention, the heating part or the heat-retaining part can be sufficiently uniformly heated or kept at the desired temperature even with a voltage of 70V or less. This is because it is possible to do so, and also takes into consideration safety measures such as preventing electric shock. In order to apply a voltage of 70V or less to the plate-shaped heating element, a commercial AC power source with a voltage of 100V, 200V or more is generally used as the primary power source, and the voltage is lowered by a transformer. What is necessary is to be able to set the required voltage of 70V or less as the secondary power source of the transformer. If the total resistance of the plate-shaped heating element required for heat generation is R, the maximum electric power required to generate heat in the plate-shaped heating element is W, and the maximum voltage to be set is .

R=V2/W However, V≦70V (as described in Type 11,
According to the heating or heat retention method of the heat treatment apparatus etc. of the present invention,
Since the heating element is plate-shaped and can be bone-shaped into any shape, it is easy to attach the heating element to a heating part or a heat-retaining part that has a complicated shape. Because of its large area, it is possible to quickly and efficiently heat the heating part or heat retention part to make the temperature uniform.Furthermore, since the heat generation temperature of the plate-shaped heating element itself is lower than that of conventional heating elements, the plate-shaped The life of the heating element can be extended.

Furthermore, according to the method for heating or keeping warm in a heat treatment apparatus, etc. of the present invention, the temperature can be easily set. If you do not necessarily need a control device that hacks the temperature sensor signal into the power supply, and there are no external factors that can significantly change the amount of heat heated in the heating section or insulation section, you can keep the set voltage constant. , it is possible to perform precise and uniform temperature control with current constantly flowing.
Heating or heat retention can be performed with little temperature change over time, and power consumption can also be reduced.

Furthermore, according to the heating or heat retention method of the heat treatment equipment, etc. of the present invention, since a low voltage is used, danger to workers can be reduced, and the construction of heat-resistant insulating materials and electrical equipment can be simplified. Furthermore, the entire device can be made more compact, and as a result, great effects such as improved work efficiency and productivity can be achieved.

Hereinafter, the heating or heat retention method of the heat treatment apparatus, etc. of the present invention will be described in further detail by giving Examples.

Example 1 As shown in FIG. 1, a heat-resistant insulating material 7, a plate-shaped heating element 8, and a heat-resistant insulating material 9 are layered one after another on the inside of a sleeve 1 of a polypropylene yarn drawing roll. It was attached using an inorganic heat-resistant adhesive. As the plate-shaped heating element 8, a 42 mesh stainless steel wire mesh cut into the shape shown in FIG. used ceramic paper with a thickness of 2 mm. Then, the core roll 2 was inserted into the sleeve 1 covered with the plate-shaped heating element 8 as described above, and both were fixed with a non-slip pin (see reference numeral 19 in FIG. 6). Next, first, the insulating sleeve 13 was passed through the roll shaft of the yarn drawing roll, and then the insulating ring 12 and one end 8a of the plate-shaped heating element 8 were passed through the insulating sleeve 13 one after another. Next, the copper plate 10 is placed on the roll shaft, the insulating ring 11 is placed on the outside of the copper plate 10, and the other end 8 of the plate-like heating element 8 is placed on the outside of the copper plate 10.
b, respectively, and then a slip ring 3 was placed on the outside thereof, an insulating ring 4 and a slip ring 5 were placed on the outside thereof, and an insulating ring 6 was placed on the outside thereof, and then fixed to the core roll 2.

As shown in FIG. 3, the slip ring 3 is composed of a copper alloy ring, and a copper alloy ring protruding from the slip ring 5 is provided for the purpose of electrically connecting the slip ring 5 to one end 8a of the plate-shaped heating element 8. Four holes 15 were bored through which the lead terminals 18 were electrically connected. As shown in FIGS. 4 and 5, the other slip ring 5 is made of a copper alloy ring, and has four protruding lead terminals 18 connected to one end 8a of the plate-shaped heating element 8. , the lead terminal 18 was covered with an insulating sleeve 16.

The roll has a diameter of 300 mm and a medium size of 550 mm, the required maximum heat generation amount is 3 KWH, and the inner surface of the sleeve 1 has a width of 500 mm and a length of 942 mm. If the plate-shaped heating element 8 is cut to have a width of about 178 mm and a length of about 30,001 mm as shown in Fig. 2, its total resistance will be 0.267 Ω, so 3 KW. It was found that in order to obtain a power of H, it is sufficient to apply a voltage of 28.3 V.

In addition, on the surface of the roll, assemble the roll as described above,
After adjusting the center of gravity balance of the roll, chrome plating was applied.

Therefore, for the above roll, the -order power source is a commercial AC 1
00V, a transformer with a secondary power supply of 30V is used, and a slider is used as the primary power supply so that the secondary power supply can be set to any voltage below 30V, and the plate-shaped heating element 8 is made to generate heat. Compared to conventional polypropylene yarn drawing rolls that use four 750W sheathed heaters powered by a 200V power supply, the roll surface temperature takes less time to reach the required uniform temperature. did not change over time, had low power consumption, and was safe.

In this example, the secondary voltage was controlled by a slider, but instead of using a slider, a tap for taking out the secondary coil or a temperature sensor was used to control the roll surface temperature to a predetermined temperature. The same purpose could be achieved by turning the power on and off.

In addition, unlike the above embodiment, in the case of a double-sided (double-shaft type) polypropylene yarn drawing roll, as shown in FIG. asbestos paper, plate-shaped heating element 8 and heat-resistant insulating material 9
Alternatively, asbestos paper with a thickness of 1 mm may be adhered with a heat-resistant adhesive using polyimide, and the sleeve 1 may be fitted on the outside of the asbestos paper. The total resistance of the plate-shaped heating element 8 is determined according to the purpose of use as described above (
The material may be selected in consideration of the workability and durability of the plate-shaped heating element 8, such as a wire mesh, within a range that satisfies formula 1).

Example 2 As shown in FIGS. 7 and 8, ceramic paper (heat-resistant insulating Material) 7 was pasted. Next, a plate-shaped heating element 8 is coated and fixed on this surface with an inorganic heat-resistant adhesive, and a ceramic paper (heat-resistant insulating material) with a thickness of 2 parts is further applied to this surface with an inorganic heat-resistant adhesive. It was fixed with a restraining plate 21 to which 9 was attached. Regarding the axial direction of the extruder barrel 20, the asbestos slate plate ring 22 allows the extruder barrel 20 to
0, the flanges at both ends and each heat zone are insulated, the end of the plate-shaped heating element 8 is fitted between the asbestos slate plate ring 22 and the conductive ring 23, and the conductive ring 23 is further inserted into the asbestos slate plate ring 24. Insulate the outside of this plate with plate 2.
1, and the holding plate 21 was fixed with bolts and NAND.

When selecting the plate-shaped heating element 8 for each heat zone, calculate the maximum heat generation power required by the extruder barrel 20, distribute it to the required heat zones, and use it in each heat zone according to the formula (11) described above. The plate-shaped heating element 8 to be used in each heat zone was selected based on the total resistance and voltage.That is, the extruder barrel 20 of this example has a screw diameter of 501 mm and a length-to-diameter ratio of 28. Yes, the maximum required heating power is 9KWH and the required heat zones are 3 zones, so if the power is distributed equally to each heat zone and 20V is used as the power supply, the entire plate-like heating element 8 of each heat zone can be used. The resistance is 0.13Ω.Therefore, the covered fixed area of the plate-shaped heating element 8 in each heat zone is rlJ285i
+■, length 400, diameter 0.252" since it is a hawk seal
If a wire mesh with two mu stainless steel wires per 1 cm in the length direction is used as the plate-shaped heating element 8, the total resistance in the length direction in this area will be 0.12Ω, so such a plate A shaped heating element 8 was used.

Further, as a power source, a 100 V AC power source was used, and this was set to 20 V or less as a secondary voltage using a transformer.

Under the above conditions, when the extruder barrel 2゜ was used to form a blown film of high-density polyethylene, it was found that the size and format were 200V power supply, a total of 10'WH hand heaters, and Compared to the same conventional extruder barrel, the extruder barrel 20 took less time to reach the required temperature, consumed less power, and was safer.

In this example, cooling of the extruder barrel 20 was not necessary, but if it is necessary to cool the extruder barrel 20 during operation due to heat generation of the screw, the current technology BL:I Either an air-cooled system using a power supply or a water-cooled system can be applied. In addition, if the required power is high and 20V results in a high current, making it difficult to handle a transformer or one-to-one line, and reducing economic efficiency, you can select an appropriate voltage below 10V. Also, the total resistance of the plate-shaped heating element 8.
In order to increase the temperature, it is necessary to use a material with high electrical resistance such as Nirarom wire or carbon fiber as the material of the plate-shaped heating element 8, or to limit the inside of the plate-shaped heating element 8 while increasing its length. Further, as the plate-shaped heating element 8, an appropriate one may be selected depending on the application and the shapes of the heating section and the heat-retaining section. Furthermore, the plate-shaped heating element 8 may be adhered to the holding plate 21 as in the fifth embodiment.

Example 3 A plate-shaped heating element was covered and fixed in the same manner as in Example 2 to a P-1 seal bar of a bag making machine or a packaging machine made of aluminum, copper, iron, or an alloy thereof. Conventional 100V or 2
Heat seal bar using 00■ power supply is medium 8II
111 A 200 WH electric wire heater with a length of 550 m11 is normally used, but according to the present invention, if a 100 W+-1 plate heating element is used for a P1-seal bar of the same size, it was good.

When the heat-seal bar according to the present invention was applied to an automatic packaging machine for automatic packaging, the heat-seal strength did not change locally or over time (the power consumption did not change). It was possible to improve the packaging speed while reducing the amount of water and safety.Also, unlike the conventional method, this automatic packaging uses a temperature sensor to turn the power on and off, making it possible to without controlling the temperature of the bar,
Although a low voltage necessary for temperature maintenance was applied to the heat seal bar at many times, the temperature of the heat seal bar did not change over time, and the temperature of the heat seal bar was uniform as a whole. When this was made into a plate, it could also be used as a heating plate for shrink packaging.

Example 4 Stretching device for stretching yarn and pan 1° tape made of polypropylene, nylon, etc. As in Example 2, a heat-resistant adhesive was first used on the back side of the heating plate to a thickness of 0°5. Ceramic paper (heat-resistant insulating material) was stuck, a plate-shaped heating element was stuck on top of it, and ceramic paper (heat-resistant insulating material) with a thickness of 10+=m was stuck on top of it. These may further be fixed with asbestos hoarding or holding plates such as metal bending plates, if necessary.

Next, the plate-shaped heating element was turned on to generate heat on the two-legged heating plate, and a predetermined work was performed.

In addition, the heating plate of the tape stretching device is composed of a curved surface.
Conventionally, a large number of plate heaters measuring about 100 m long and 100 m+i wide were installed and a voltage of about 100 V or 200 V was applied to them, but by using a plate-shaped heating element as described above, the heating plate can be It was possible to heat evenly and continuously.

In addition, according to the conventional method, the required power was 3°2 WJ per l cf (but in this embodiment, the required power was 1 c+
It was possible to achieve 2.5 W H per +1 without decreasing. Furthermore, although the control was performed by maintaining the secondary voltage of the transformer at a constant value, it is also possible to turn the power on and off using a temperature sensor and a control device as in the past.

Example 5 A tie made of an inner-layer film with an outer diameter of 250 mL and a height of 300 mff1 was surrounded by a plate-shaped heating element and rounded to keep it warm. That is, as in Example 2, as shown in FIG.
01111 ceramic paper (heat-resistant insulating material) 7
, a plate-shaped heating element 8, which will be described later, and ceramic felt (heat-retaining material and heat-resistant insulating material) 9 are adhered with a heat-resistant adhesive, and the outside thereof is further held down by a holding plate 21, and the holding plate 21 is covered with an insulating moon sleeve. They were joined by a porto and a nut 25. And these members 7.8.9.21
(hereinafter referred to as the heater in this embodiment) is shown in Fig. 9-H.
It was divided into two parts, top and bottom, and covered and fixed with ties. In addition, in FIG. 9, 26.26, 26.26 are plate-shaped heating elements 8,
These and ceramic felts 9, 9 at both ends of 8.
The heat-resistant insulating material 27.27 is a copper plate that is brought into contact with the right end of the plate-shaped heating elements 8, 8 from the inside.
・A wire (U shown in the figure) is connected, and both copper plates 27.
An insulating material 28 is interposed between 27. In addition, 91 m1 and 29 are interposed at the left end of the plate-shaped heating element 8.8, and the left ends of the plate-shaped heating element 8.8 are connected to this copper plate 29.
There is no conduction through. Further, the two-legged heater may be provided with a hole for a temperature sensor attached to the die. Furthermore, five heaters with an inner diameter of 250 mm and a height of 6011 m were used.

The power required to generate heat from each heater is determined by distributing the maximum required power of the tie to each heater. In the case of this example, the required maximum power is 10KWH, so this is distributed equally among the five heaters. Once distributed, the power per heater is 2 K W I-1.

Therefore, if the voltage is 20V, then according to equation (1) above,
The total resistance of the plate-shaped heating element 8 per heater is 0°2Ω
Therefore, the heater 1 (the plate-shaped heating element 8 per circumference was 11,360 mm long, 785 V11 long, did not exhibit the above resistance value, and was made of a 42-mesh stainless wire mesh).

When a high-density polyethylene blown film was manufactured using the above heater, it was found that
Compared to using a conventional heater powered by 0V, we were able to produce a film with a more uniform thickness. In addition, conventionally, when a split heater was used, the temperature unevenness at the bonding portion often caused vertical slits in the film, but in this example, such inconvenience did not occur at all. or,
In this example, the temperature of the tie could be easily maintained at a predetermined temperature without performing feedback control of the power supply based on the temperature of the tie, and a good product was obtained even in this case.

Example 6 On the back side of a hot plate 1- with a length of 250 mm and a width of 300 +*m, a plate-shaped heating element 8 made of a stainless steel wire mesh with a diameter of 40 mm and a length of 1500 mm as shown in Fig. 10 was placed.
As in Example 2, heat-resistant insulating materials were arranged on the top and bottom, and they were attached using a heat-resistant adhesive.

The total resistance of the plate-shaped heating element 8 is 0.6Ω, and its power consumption is 1.000WH119 when a voltage of 24.5V is applied.
600WH when a voltage of V is applied 300WH when a voltage of 813V is applied
It was WH.

When using the above hot play 1, the temperature rise rate of the iron plate was faster than the conventional product that uses a 100μ power supply.
, the temperature was uniform, safe, and energy-saving.

The plate-shaped heating element 8 of this embodiment does not necessarily have to be a stainless steel wire mesh, and may be a flat plate made of a material with appropriate electrical resistance, such as nichrome wire or carbon fiber. In addition, the plate-shaped heating element 8 of this embodiment can also be used in cooking heaters such as pots, pots, electric rice cookers, irons, etc., and even in large boiling machines, etc. - It could also be used as a heating source in place of steam.

Example 7 For the purpose of preventing water pipes from freezing, a heat-resistant insulating material with a thickness of l is sequentially applied to the necessary locations on the outer surface of a water pipe with an outer diameter of 34 mm.
Asbestos paper of 80 mm thick was attached as a plate-shaped heating element, wire mesh of 80 mm thick was attached as a heat-resistant insulating material, and asbestos paper of ζ 2 mm thick was attached as a heat-resistant insulating material.

When a voltage of 15V was applied per 5m to the plate-shaped heating element, the water in the water pipes did not freeze even when the outside temperature reached 130°C, and there was no danger at all from passing the current. I didn't.

In addition, the heat-resistant insulation 4A material is not limited to asbestos paper,
Plastic films such as polyolefin, polyvinyl chloride, polyester, and the like can also be used, and in that case, a heat-resistant adhesive that is compatible with the heat-resistant insulating material may be selected.

Furthermore, if the water pipe is already coated with polyolefin, polyvinyl chloride, etc., the plate-shaped heating element may be directly coated and fixed on the surface. Also, in the case of a water pipe made of a non-conductive material such as polyvinyl chloride, a plate-shaped heating element may be directly coated and fixed on the surface of the water pipe. Further, in order to protect the water pipe, a plate-shaped heating element and a heat-resistant insulating material may be adhered to the inside of the galvanized iron or plastic tape as in Example 5, and the water pipe may be covered with these. Also, using temperature sensors and controllers,
It is also possible to incorporate a system that allows current to flow through the plate-shaped heating element when the temperature around the water pipe falls below 0'C. In addition, the fluid inside the pipe is limited to water, and the use of the above-mentioned plate-shaped heating element is limited to liquids that solidify or whose viscosity decreases due to a drop in temperature, or gases such as air that contain water droplets. It is also useful as a countermeasure for problems caused by low temperatures when transporting such items.

[Brief explanation of the drawing]

The drawings all show the main parts of a heat treatment apparatus or heat retention apparatus to which the heating or heat retention method of the present invention is applied, and FIG. 1 shows the main parts of a cantilevered yarn drawing roll. 2 is a schematic plan view of the plate-shaped heating element used in FIG. 1, FIG. 3 is a front sectional view of one slip ring used in FIG. 1, and FIGS. Figure 5 is the first
A front cross-sectional view and an enlarged side cross-sectional view of one of the slip rings used in the figure, Figure 6 is a side cross-sectional view of the main part of the double-supported yarn drawing roll, and Figure 7 is a schematic cross-sectional view of the extruder barrel. , Fig. 8 is an enlarged view of the main part of Fig. 7, Fig. 9 is a front sectional view of the main part of the inflation device, and Fig. 10 is a schematic plan view of the plate-shaped heating element covered and fixed on the back side of the hot plate. It is a diagram. 1. Sleeve of yarn drawing roll (heating part) 7. Heat resistant insulating material 8. Plate heating element 9. Heat resistant insulating material 20. Extruder barrel (heating 01l) 21. Patent application filed People Hiraiwa Sadamichi Yuikeda

Claims (5)

[Claims] (1) A method for uniformly heating or keeping warm a heating part or a heat-retaining part of a heat treatment device, etc., wherein the heating part or heat-retaining part includes:
A plate-shaped heating element that can be shaped into any shape is covered and fixed with a heat-resistant adhesive with a heat-resistant insulating material interposed therebetween, and a commercial frequency AC or DC voltage of 70 V or less is applied to the plate-shaped heating element. A method for heating or keeping warm in a heat treatment apparatus, etc., characterized in that the plate-shaped heating element generates heat. (2) The plate-shaped heating element is made of iron, nickel, chromium, titanium,
Metals such as copper and aluminum, their alloys, and graphite,
Claim (1), which is formed by molding one or more conductive materials such as carbon fiber into a plate, foil, perforated plate, wire mesh, punched wire mesh, or continuous mesh. Heating or heat retention method using the heat treatment equipment described above. (3) Claim No. 1, wherein the heat-resistant insulating material is an inorganic heat-resistant insulating material such as ceramic paper or asbestos, or an organic heat-resistant insulating material such as Teflon or polyimide.
A method for heating or keeping warm using the heat treatment apparatus described in item 1. (4) When fixing the plate-shaped heating element to the heating part or heat retention part,
A holding plate is used together with a heat-resistant adhesive, and if the holding plate is a conductor, a heat-resistant insulating material is interposed between the holding plate and the above-mentioned plate-shaped heating element, and these are heat-resistant as necessary. A heating or heat-retaining method for a heat treatment apparatus or the like according to claim (1), which comprises bonding with an adhesive. (5) A heat treatment device, etc. according to Claim No. +11, wherein a heat-resistant insulating material is coated and fixed with a heat-resistant adhesive on the surface of the plate-shaped heating element on the side opposite to the heating section or the heat-retaining section. method of heating or keeping warm.