JP3187443B2 - Heat peeling device for metal surface coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention, only the metal surfaces locally and efficiently electromagnetic induction heating, easily peeled off coating applied over the metal surface, pressurization of metal surface coating to be removed
Relates to a heat stripping device, in particular, the thermally releasable suitable metal surface coating when used for heating separation of the bottom plate metal surface coating of various tanks
Related to the device .

[0002]

2. Description of the Related Art A coating film, a coating film or an adhesive film applied to a metal surface forming an outer wall, an inner wall, or a floor surface of various large-diameter tanks such as oil and gas must be peeled off for repair or repair. May not be. Conventionally, as a method of peeling off the film on the metal plate, a method of physically peeling off, a method of softening with a solvent, a method of softening the film by heating and peeling off, and the like are known.

[0003] However, the above-described conventional method of peeling off a film applied on a metal plate has the following problems. First, since the method of physically peeling off the film is performed by sandblasting, a vibration tool, or spraying high-pressure water, there is a problem that dust, vibration, noise, or rust is generated. In particular, in the method using sandblasting, dust is generated, so that the working environment is poor, the time required for peeling work and the like is increased, and the metal plate is greatly worn. In addition, the method of stripping the coating with a solvent or a stripping agent has a problem in that harmful gas is generated and poisoning by the solvent is easily caused.

Further, the method of softening and peeling the coating by heating such as flame or electric heat requires measures against combustion gas, and it takes a long time to heat the whole metal. Since the metal is heated to a high temperature, there is a problem that the mechanical strength of the metal tends to decrease.

[0005] In view of these problems, the following proposals have recently been made. First, Japanese Patent Application Laid-Open No. 633-100000 proposes a technique in which a metal is heated to a temperature at which the mechanical strength is not impaired by induction heating, and the coating is peeled from the steel pipe. Secondly, Japanese Patent Application Laid-Open No. 2-30087 proposes a technique of self-heating a metal surface by high-frequency induction heating to peel off a coating film. Thirdly, Japanese Patent Publication No. 63-67100 proposes a method in which a metal surface is heated by induction heating to reduce the adhesion strength of a lining material or a thick-film coating material and to peel off the material.

[0006]

However, the following problems remain in the above-mentioned technology that has been conventionally proposed. That is, the technique disclosed in Japanese Patent Application Laid-Open No. 633-100000 is intended for a metal pipe and cannot be applied to a tank having a large area such as a tank.

[0007] The technique of Japanese Patent Application Laid-Open No. 2-30087 does not disclose any frequency conditions for intensively heating the metal surface portion, and also discloses one side of a metal plate coated on both sides. There is no disclosure of stripping or removing only the coating.

Furthermore, techniques of JP-B 63-67100, since the heating unit and the high frequency generator is in the separate, exemplary apparatus with operability in size is deteriorated, the heating part and the high-frequency generator The interval between them becomes longer, and the loss of high frequency becomes larger, resulting in lower efficiency. In addition, since the heating section does not have a core, electromagnetic waves leak from the heating section. Therefore, if the high-frequency generator is arranged near the electromagnetic induction coil, the leaked electromagnetic wave heats the high-frequency generator and adversely affects the operator.

[0009] Furthermore, these prior art, in terms of the size of the apparatus, in order to obtain a high output, device could not bear a very long period of use becomes high heat. As described above, an apparatus capable of treating a large area at a time using high-frequency induction heating and enduring long-term use has not yet been developed. In addition, a device having a high-frequency generation unit and a heating unit integrated with each other has not yet been developed for efficient and efficient use in a tank. Further, there has not yet been developed an apparatus used in a place where the metal plate is not flat and a metal plate is partially double or triple like a welding line.

[0010] The present invention has been made in view of the above circumstances, only be locally and efficiently induction heated metal surface, easily peeled film was to be removed metals
An object of the present invention is to provide a device for heating and peeling a surface coating .

[0011]

In order to achieve the above object, the present invention provides an apparatus for heat-peeling a metal surface film, comprising:
And dividing the electromagnetic induction coil and the core of the electromagnetic induction unit,
The split cores are vertically independent of each other.
And linked so that they can be moved
The electromagnetic induction coils are arranged side by side in the longitudinal direction, and
The distance between the electromagnetic induction coils
The configuration is narrower than the center gap of the induction coil.
More preferably, the shock absorber is provided independently on each of the divided cores of the electromagnetic induction section, and two cores of the electromagnetic induction section are further provided on the core of the electromagnetic induction section.
And an electromagnetic coil between the two electromagnetic induction coils.
Is configured to be variable .

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1A is a side view showing an apparatus for heat-peeling a metal surface film according to an embodiment of the first apparatus invention, FIG.
(B) is a partial sectional view similarly. In the drawings, reference numeral 1 denotes an apparatus main body that heats and peels a metal surface coating such as a tank, and includes a bottom plate 10, an electromagnetic induction unit 20, and a control unit 30. And an electromagnetic induction unit 2 for heating the metal plate.
0 and a control unit 30 including a high-frequency generation unit that supplies high-frequency power to the electromagnetic induction unit 20 are integrally formed close to each other. That is, the electromagnetic induction unit 20 is provided with the shock absorbing material 40 (for example, a rubber damper, a spring, a leaf spring, or the like) in a state where a slight gap is provided below the outer box in which the control unit 30 is built.
Are connected via Thereby, even if there is some unevenness on the floor surface, the impact is absorbed by the impact absorbing material 40, and the contact property of the bottom plate 10 can be improved. When a rubber damper is used, it is preferable to use a heat-resistant material.

Further , when the electromagnetic induction section 20 and the control section 30 are integrated in close proximity to each other, the size of the entire apparatus is reduced and the loss of electromagnetic waves is reduced. The term “integrated” means that the devices are integrated when the device is used, and does not necessarily mean that they are physically integrated. Further, the apparatus main body 1 is provided with a handle 2, a power cord 3, a cooling hole 4, and a caster 5.

[0014] bottom plate 10 apparatus constitutes a bottom surface of the main body 1, the coating was applied over a metal floor 51 50 (typically 0.
(Thickness of about 1 to 5.0 mm). It is preferable that the bottom plate 10 is formed of a material having excellent high temperature resistance and impact resistance. As such a material, for example, a heat insulating plate (manufactured by Brandenburger; KV3) made of heat-resistant polyimide and glass fiber, or an inorganic heat insulating plate (manufactured by Hirodenshi;
Super Insulation ROSNA) and the like. When the bottom plate 10 made of these materials is used, the metal plate 5 can be used without hindering the high-frequency electromagnetic induction operation described later.
1 is prevented from being transmitted to the core 22, and the device can be operated for a long time.

In particular, in order to heat the metal plate 51 quickly and to a high temperature, it is necessary to bring the electromagnetic induction coil 21 as close as possible to the metal plate 51 and to reduce the distance between them.
When the coil 21 is brought close to the metal plate 51, the heat of the heated metal plate 51 is transmitted to the core 22 and the magnetization performance of the core 22 is reduced. However, if the above-mentioned heat insulating plate made of heat-resistant polyimide and glass fiber is used, the core 22 can be brought close to the metal plate 51 without deteriorating the magnetization performance, and rapid and high-temperature heating can be performed.

Reference numeral 20 denotes an electromagnetic induction unit, which includes an electromagnetic induction coil 21 and a core (magnetically permeable member) 22. Core 2
Numeral 2 is formed of a magnetic material having an insulating property, and is mounted on the bottom plate 10 as shown in FIG. The electromagnetic induction coil 21 is wound around the core 22. The core 22 has a function of causing the metal plate to absorb the lines of magnetic force diverging into the space above the electromagnetic induction coil 21 downward.

[0017] Here, the core 22 is so weak against impact, to mitigate the impact on the core 22, it is bonded and fixed by an adhesive or the like so as to suspended the core 22 on the box of the electromagnetic induction unit 20. Further, between the core 22 and the bottom plate 10, 0.5
A shock absorber made of a silicon plate or the like having a size of about mm may be provided to reduce the impact applied to the core 22.

Reference numeral 30 denotes a control unit, which is mounted inside the apparatus main body 1 and includes a high-frequency generation unit (not shown) for generating high-frequency power and a control unit for performing various controls of the apparatus. The high frequency generator of the controller 30 is connected to the electromagnetic induction coil 21. Therefore, the high-frequency power generated by the high-frequency generator is supplied to the electromagnetic induction coil 21 to generate an alternating magnetic field, and an eddy current flows on the surface of the metal plate 51 by the high-frequency electromagnetic induction to cause the metal plate to generate heat.

The frequency of the high frequency is generated by a high frequency generator power is preferably set to 9～30KHz, especially 10
Preferably, the frequency is set to 20 kHz. Above 30 KHz is not realistic. On the other hand, if the frequency is lower than 9 KHz, the material located on the opposite side of the metal plate is heated undesirably because it is heated deep inside the metal plate.

The relationship between the high frequency f (Hz) and the effective depth of eddy current generation (heated depth) δ (in) is represented by the following equation (1) (where μ Is the magnetic permeability, and ρ is the electrical resistance of the steel).

[0021]

(Equation 1)

[0022] Thus, by substituting the value of the frequency f in the above equation (1) can be obtained approximate value of the heated the depth. For example, when the frequency f is 11.5 KHz, the heated depth is 0.46 mm.

Examples of the high-frequency generator, in order to shorten the heating time, it is preferable to use one which can supply large power. FIG. 3 shows an example of the circuit configuration of the high frequency generator.
In the figure, three-phase alternating current (200 V, 60 to 100
A) 32 is DC-converted by a rectifier 33, smoothed by a reactance 34 and a capacitor (3000 μF) 35, and a high-frequency pulse current P (sawtooth wave) (9 to 30 KHz, 200
A) and is supplied to the electromagnetic induction coil 21.

Next, heat stripping method is described using the heating device for peeling off the metal surface coating having the above structure. First, as shown in FIG. 1B, the bottom plate 10 of the apparatus main body 1 is brought into contact with the coating 50 applied on the surface of the metal plate 51. Next, the electromagnetic induction coil 2
1 is supplied with high-frequency power to locally heat only the surface of the metal plate 51, whereby the coating 50 is peeled off by heating. Usually, the coating is turned up by heating and peels off spontaneously, but a part which adheres firmly and is hard to peel off can be easily peeled off by using a scraper or the like. The processing time is 1 to 50 seconds, and the processing temperature is 50 to 30 seconds.
It is preferable to control the controller 30 so that the temperature is 0 ° C.

Next, another embodiment of a heating device for peeling off the metal surface coating will be described with reference to FIG. This apparatus for heat-peeling a metal surface coating is provided with two or more electromagnetic induction coils adjacent to each other on a bottom plate, and is preferably configured so that the directions of currents flowing in adjacent electromagnetic induction coils are opposite to each other. .

When two sets of the electromagnetic induction coil 21 and the core 22 are arranged on the bottom plate 10, when currents in opposite directions (the A direction and the B direction in the drawing) are applied to the respective electromagnetic induction coils 21a and 21b, the illustration is omitted. More electromagnetic energy can be supplied to the H portion than other portions, the temperature of this portion can be higher than that of the other portions, and the coating or the like can be softened and peeled in a short time. In this case, it is preferable to supply high frequency power of 10 to 20 KHz to the electromagnetic induction coil 21.

When two sets of coils and cores are provided as described above, two sets of high frequency generating circuits in the control section are also provided, and each of the coils 21a and 21b is driven by a different high frequency generating circuit. Can also. This allows
The burden on the high frequency generator is reduced, and the device can be used for a long time. In addition, since the problem of insufficient capacity of a capacitor or a transistor is solved, it is possible to improve the processing capacity and increase the processing area.

The present invention is not limited to the above embodiment, but can be implemented with appropriate modifications within the scope of the present invention. For example, the control unit needs to be cooled for continuous use. In this case, a cooling radiator using a cooling heat pipe 24 may be attached to the surface of the control unit to suppress a rise in temperature of the control unit 30. The heat pipe 24 has a working fluid sealed inside the pipe,
This working fluid is heated at one end of the pipe and evaporates, moves at a high speed to the other end of the pipe, releases latent heat, and condenses to conduct heat at high speed. A heat pipe can conduct heat several hundred times more than a metal rod of the same diameter. It is preferable to attach fins to the heat pipe in order to increase heat radiation efficiency. As the heat pipe, any of bottom heat, horizontal heat and top heat can be used. The use of the heat pipe suppresses a rise in the temperature of the control unit, avoids a failure of the transistor of the control unit due to the rise in temperature, and enables the device to be used for a long time.

As shown in FIGS. 5 (a) and 5 (b), FIGS. 6 and 7, the bottom plate 10 and the core 22 may have a divided structure and may be connected by a hinge 23. In this manner, even in a place where there is a step in the welding line W such as an iron plate, the grounding property of the bottom plate 10 can be enhanced, and the gap between the bottom plate 10 and the metal plate can be reduced. In particular,
As shown in FIG. 6 and FIG.
However, the cores 22 are moved independently in the vertical direction, and the cores 22 are constantly pressed downward by the shock absorbing material 40.
This is effective.

In many cases, the temperature of the welded portion (line) W is unlikely to rise because the metal plates are superposed. Therefore, it becomes necessary to concentrate heat as compared with other parts. For this reason, it is effective to use a device modified as follows. That is, as shown in FIG. 8, long coils 21a and 21b are formed along the welded portion (line) W, and two of them are arranged in the longitudinal direction. The distance L1 between the two coils is defined as the center gap L between the coils 21a and 21b.
2 and the coils 21a, 21b
A reverse current is applied to the By doing so, the coil 21
The heat is concentrated more between the coils 21a and 21b than directly below the a and 21b, and the welded portion where the metal plates are overlapped can be made to reach the target temperature in the same time as the normal flat portion. .

Furthermore, two coils 21a, 21b in the core 22 which is arranged, as shown in FIG. 9, the coil 2
When the shape of the protrusion between the coils 1a and 21b is omitted, heat is more easily concentrated between the coils 21a and 21b. Further, the cores 22a, 22 provided with the coils 21a, 21b are provided.
If the distance S (see FIG. 10) between the cores 22a and 22b can be changed, the distance between the cores 22a and 22b, ie, the coil 2
The distance S between 1a and 21b can be adjusted.

[0032] Furthermore, more than one place of the bottom plate 10, for example six positions, the bottom plate 10 and when the configuration in which embedded mark members 11 of different colors in about 2/3 of the depth of the bottom plate (Fig. 1
1), when the bottom plate 10 is worn by use, the marker member 11 is exposed to easily inform that the time for replacement of the bottom plate 10 has come.

[0033]

EXPERIMENTAL EXAMPLES AND COMPARATIVE EXAMPLES The coating on the test bottom plate simulating the bottom plate of an oil storage tank was removed using the apparatus for heat-peeling a metal surface coating shown in FIG. (Experimental Examples 1 to 25 and Comparative Examples 1 to 5). In the peeling treatment, as shown in FIG. 1B, the coating film heating and peeling apparatus 1 is placed on the floor at the portion to be peeled, and the bottom plate 10 is brought into contact with the coating 50 applied on the floor 51. Electromagnetic wave of 11.5 KHz
1 and held for a certain period of time, and then the film heating and peeling apparatus 1 was moved to the next peeling portion.

[0034]

[Table 1]

[0035]

[Table 2]

[0036]

[Table 3]

[0037]

[Table 4]

The above experimental results, when using the present invention apparatus, the coating of moving simultaneously with the heated portion of the apparatus is easily peeled off. Further, the coating that did not partially peel could be easily peeled off using a metal scraper or the like. In addition, asphalt sand layer 5 formed under the test bottom plate
No. 2 was also observed. In the case of this apparatus, no heat was transmitted, and there was no phenomenon in which the oil contained in the asphalt sand layer 52 evaporated to form bubbles. Further, even after about three hours of use of the device, the temperature of
The temperature did not exceed 0 ° C., and no decrease in the magnetization performance of the core occurred.
It was also found that there was no risk of transistor failure in the control unit due to core temperature rise. In the tables, A type, B type, and C type indicate the bonding state of the test bottom plate shown in FIGS. 12, 13, and 14.

Next was performed collecting the release film or Haisuna performed in association with the separating operation of the coating film of oil tanks, the comparison of all the working days, including the cleaning of internal tank.

When the apparatus according to the present invention is used, not only the number of days required for peeling off the coating film is shortened, but also the inspection work can be performed in parallel with the peeling work by the heat peeling apparatus, as compared with the conventional sandblasting method. Therefore, the total number of working days is reduced. Further, since there is no damage to the metal plate as in the sandblasting method, the number of days required for repair is small, and the total number of working days is further reduced.

[0041]

As described above, the metal coating of the present invention
According to the heat peeling device , only the metal surface can be locally and efficiently subjected to electromagnetic induction heating, and the coating applied to the metal surface can be easily peeled and removed. Further, since the device can be used efficiently for a long time even though the device is small, it is excellent in operability and economy.

[Brief description of the drawings]

FIG. 1 is a view showing an apparatus for heat-peeling a metal film according to the invention, FIG. 1 (a) is a side view, and FIG. 1 (b) is a partial sectional view.

FIG. 2 is a perspective view showing an example of an electromagnetic induction unit of the device invention shown in FIG.

FIG. 3 is a circuit diagram showing an example of a high-frequency generator of the device invention shown in FIG.

FIG. 4 is a perspective view of an electromagnetic induction unit in the apparatus for heat-peeling a metal film according to the invention;

FIG. 5 is a view showing an embodiment in which an electromagnetic induction unit is divided;
FIG. 5A is a perspective view and FIG. 5B is a sectional view.

FIG. 6 is a diagram showing an embodiment in which an electromagnetic induction unit is divided;
It is a side view of the example using two hinges.

FIG. 7 is a diagram showing an embodiment in which an electromagnetic induction unit is divided;
It is a side view of the example using one hinge which has a long hole.

FIG. 8 is a bottom view of an example in which the electromagnetic induction portion is formed long along the welding line.

FIG. 9 is a sectional view showing an embodiment in which an intermediate portion of a core in the electromagnetic induction section is omitted.

FIG. 10 is a sectional view showing an embodiment in which a length between coils (cores) in an electromagnetic induction unit can be adjusted.

FIG. 11 is a sectional view of a main part of an embodiment in which a marker member is embedded in a bottom plate.

FIGS. 12A and 12B are views showing a type A joint state of the test bottom plate, wherein FIG. 12A is a plan view and FIG. 12B is a right side view.

13A and 13B are views showing a joint state of the B type of the test bottom plate, wherein FIG. 13A is a plan view and FIG. 13B is a right side view.

14A and 14B are views showing a joined state of the C type of the test bottom plate, wherein FIG. 14A is a plan view and FIG. 14B is a right side view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Heat-peeling apparatus of a metal film 10 ... Bottom plate 20 ... Electromagnetic induction part 21 ... Electromagnetic induction coil 22 ... Core 30 ... Control part

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-30087 (JP, A) JP-A-59-176100 (JP, U) JP-A-62-91845 (JP, U) 33515 (JP, B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) H05B 6/10 B44D 3/16

Claims (3)

(57) [Claims] 1. A bottom plate in contact with a surface to be peeled off, an electromagnetic induction portion comprising an electromagnetic induction coil and a core provided on the bottom plate, and a gap provided with the electromagnetic induction portion and integrally formed through a shock absorbing material. A heating and peeling device for a metal surface coating, comprising: a high-frequency generation unit that supplies high-frequency power to the electromagnetic induction unit; wherein the bottom plate and the electromagnetic induction coil and the core of the electromagnetic induction unit are provided.
Divide and separate the divided cores vertically
And connected so that they can move independently.
The divided electromagnetic induction coils are arranged side by side in the longitudinal direction,
And, the interval between these side-by-side electromagnetic induction coils,
It is noteworthy that the center gap of these electromagnetic induction coils was narrower.
Heat stripping equipment for metal surface coatings . 2. The apparatus for heat-peeling a metal surface coating according to claim 1, wherein said shock-absorbing material is provided independently on each of said divided cores of said electromagnetic induction part . 3. The core of the electromagnetic induction section has two electric wires.
In addition to disposing a magnetic induction coil, the two electromagnetic induction
2. The method according to claim 1, wherein the distance between the coils can be changed.
Heat peeling device for metal surface coating .