JP2010129406A - Temperature monitoring system for induction heating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a temperature monitoring system for an induction heating device capable of effectively performing a maintenance and inspection operation in a short time by detecting temperature abnormality while temperature conditions of a bus-bar and a joining bolt of the bus-bar are monitored with a simple device without having influence of an induction magnetic flux from a heating coil and by planning locations to be inspected and a maintenance plan in advance. <P>SOLUTION: Temperature-sensitive capsules 17 in which a liquid 20 to generate a smelling gas 19 is sored in a container 18 formed of a non-magnetic material, and sealed with a solder 21 to melt at a designated heat-sensitive temperature are mounted on the bus-bar 8 and the joining bolt 16 of the bus-bar 8 of a power source section 5 covered by a cover 9 of the induction heating device; a smell detector 22 to detect the smelling gas 19 is mounted inside an upper part of the cover; and the smell detector 22 is connected with the monitoring system 23. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a temperature monitoring system for detecting abnormal heating of a bus bar attached to a power supply unit of an induction heating apparatus for heating or heat-treating a rolled material or other heated material in a steel line.

In general, in a hot rolling line, a material to be heated (rolled material) is heated to a temperature that can be rolled in a heating furnace, and is formed into a state called a rough rolling bar by a rough rolling mill. Furthermore, the product which has a desired board pressure and board width is obtained by applying a rough bar to a finishing mill. In such a hot rolling line, in recent years, it has become a common means to install an induction heating device for the purpose of reducing the load on the rolling mill due to the temperature drop of the steel material, raising the temperature, and soaking. As such an induction heating apparatus, an edge heater for the purpose of increasing the temperature of both edge portions of the material to be heated and a bar heater for the purpose of increasing the temperature of the entire material to be heated are generally known.

As shown in FIG. 7, an induction heating device that is a conventional bar heater includes, on a carriage 1, an inductor 4 that includes a solenoid-like heating coil 3 that raises the temperature of the entire material to be heated 2, an iron core, and the like to generate magnetic flux, The power supply unit 5 supplies power to this. The power supply unit 5 is provided with a bus bar 8 for supplying power to the capacitor 7 and the heating coil 3, and is covered with a cover 9.

The condenser 7, the bus bar 8, and the heating coil 3 are connected to the water supply main pipe 12 and the drainage main pipe 10 by a cooling water hose 11, and are each cooled by water. The water-cooled cooling water is discharged from the drain mother pipe 10 at once. A flow meter 13 is attached to the outlet side of the water supply mother pipe 12, and a thermostat 14 is attached to the drain mother pipe 10 to measure the cooling water temperature.

Such an induction heating apparatus has been operated for a long period of time, and the equipment may have to be shut down due to a sudden accident such as aging of the apparatus or burning due to secular change due to vibration. In particular, bus bars and bolts that connect bus bars through which a large current flows are used in harsh environments, and the temperature may increase over time, leading to failure.

Since the bus bar 8 passes a large current of the heating power source, the temperature rises due to Joule heat. When used at a high temperature over time, a thin oxide film is formed on the joint surface. Since the oxide film has a high resistance, the contact resistance value is increased and the temperature further increases. As the temperature of the bus bar 8 rises, the bus bar joint bolt also rises in temperature. However, since the bolt extends due to the thermal expansion of the metal, the contact pressure of the contact surface of the bus bar 8 becomes loose. Oxygen in the air is supplied to the gap between the joint surfaces due to the loosening, so that the oxide film becomes thicker. Such repetition may increase the temperature over time, lower the heating efficiency, and may cause a failure.

As a countermeasure, a number of thermostats and thermocouples can be attached to the busbars and busbar joint bolts to monitor temperature abnormalities. However, the wiring structure is complicated, and in particular, the thermocouple uses the induction magnetic flux from the heating coil 3. There was a problem that accurate temperature measurement was difficult because of the influence of

For this reason, although periodic maintenance inspections are performed, the structure of the induction heating device is complex, and long-term line stoppage days must be used for identifying faults and deteriorated parts and for maintenance inspections. However, there was a problem that much labor and cost were required.

The present invention improves the above problems, and detects temperature abnormalities in the induction heating device by monitoring the temperature status of the bus bar and bus bar joint bolt with a simple device without being influenced by the induction magnetic flux from the heating coil. Thus, it is an object of the present invention to provide a temperature monitoring system for an induction heating device that can prepare an inspection point and a maintenance plan in advance and can efficiently perform maintenance and inspection work in a short time.

In the temperature monitoring system for an induction heating device according to claim 1 of the present invention, a substance that generates odorous gas is housed in a container formed of a non-magnetic material and sealed with solder that melts at a predetermined heat sensitive temperature. The temperature-sensitive capsule is attached to the bus bar of the power supply section covered with the cover of the induction heating device or / and the joint bar of the bus bar, and an odor detector for detecting odorous gas is installed inside the upper cover, and this is monitored. It is characterized by being connected to.

The temperature monitoring system for an induction heating device according to claim 2 of the present invention is the temperature monitoring system for an induction heating device according to claim 1, wherein the power source portion covered with the cover is separated into a plurality of space portions, and the bus bar of each space portion and / or the bus bar joining bolt Each of the thermosensitive capsules is attached, and an odor detector for detecting odorous gas is attached inside the upper space.

The temperature monitoring system for an induction heating device according to claim 3 of the present invention is the temperature monitoring system according to claim 1 or 2, wherein the temperature-sensitive capsule is sealed with solder that melts at different temperatures, and different types of odor It is characterized by containing a substance that generates gas.

According to the temperature monitoring system for an induction heating device according to claim 1 of the present invention, the bus bar and the joining bolt through which a large current flows rises due to the influence of the oxide film, and the temperature-sensitive capsule attached thereto is also Since the container is made of a nonmagnetic material, it is heated to the same temperature as the bus bar and the joining bolt without being affected by the leakage magnetic flux. When the temperature-sensitive capsule reaches a predetermined temperature, the solder that has sealed the container is melted, and the internal substance is heated to generate odorous gas. This odorous gas is sensed by an odor detector attached to the ceiling side, and this signal is sent to the monitoring device. With this signal, do not check immediately, but include it as an inspection item in the inspection plan for the next maintenance inspection day. You can decide what to do.

According to the temperature monitoring system for an induction heating device according to claim 2, the power supply part covered with the cover is separated into a plurality of space parts, and the temperature sensitive capsules are attached to the respective bus bars and joining bolts. Can be easily identified and can be checked in a short time.

According to the temperature monitoring system for an induction heating device according to claim 3, the thermosensitive capsules are sealed with solders that melt at different temperatures, and contain substances that generate different types of odorous gases. Therefore, it is easy to set a predetermined monitoring temperature.

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. The induction heating apparatus includes a carriage 1, a solenoid-like heating coil 3 that raises the temperature of the entire material to be heated 2, an inductor 4 that generates a magnetic flux by an iron core and the like, and a power supply unit 5 that supplies power to the inductor 4. It is installed.

The power supply unit 5 is provided with a bus bar 8 for supplying power to the capacitor 7 and the heating coil 3, and is covered with a cover 9. The condenser 7, the bus bar 8, and the heating coil 3 are connected to the water supply main pipe 12 and the drainage main pipe 10 by a cooling water hose 11, and are each cooled by water. A flow meter 13 is attached to the outlet side of the water supply mother pipe 12, and a thermostat 14 is attached to the drain mother pipe 10 to measure the cooling water temperature.

As shown in FIG. 2, temperature sensitive capsules 17 </ b> A to 17 </ b> C are bonded to the bus bar 8 and the joining bolt at the connection portion of the bus bar 8. As shown in FIGS. 3 and 4, the thermosensitive capsule 17 generates odorous gas 19 in a hollow cylindrical container 18 formed by combining hollow cylindrical half-shaped container members 18A and 18B made of a nonmagnetic material. The liquid 20 to be stored is stored, and the butted portions of the container members 18A and 18B are joined and sealed with solder 21 that melts at a predetermined heat sensitive temperature. As the nonmagnetic material forming the container 18, for example, copper or stainless steel is used.

As shown in FIG. 2, for example, as shown in FIG. 2, three types of temperature-sensitive capsules 17A to 17C that are attached to the bus bar 8 are attached. The temperature-sensitive capsules 17A to 17C are joined by solder 21 that melts at respective operating temperatures, and liquids 20 that generate odorous gases 19 having different odors corresponding to the operating temperatures are enclosed.

Further, an odor detector 22 is attached to the inner ceiling surface of the cover 9 above the temperature sensitive capsules 17A to 17C as shown in FIG. As shown in FIG. 5, the odor detector 22 includes three odor detectors 22A, 22B, and 22C so as to detect the odorous gas 19 corresponding to the operating temperature. The odor detector 22 is connected to an external monitoring device 23 as shown in FIG.

In the induction heating apparatus having the above-described configuration, the bus bar 8 passes a large current of the heating power source through the heating coil 3, and thus the temperature rises due to Joule heat. When used at a high temperature over time, an oxide film having a large resistance is formed on the joint surface, and the temperature of the bus bar 8 rises. As the bus bar 8 rises in temperature, the temperature of the joining bolt 16 also rises. Since the temperature sensitive capsules 17A to 17C are joined to the bus bar 8 and the joining bolt 16, the container 18 is also heated.

For example, when the temperature-sensitive capsule 17A attached to the bus bar 8 and operating at 80 ° C. reaches 80 ° C., the solder 21 sealing the container 18 is melted as shown in FIG. Gas 19 is generated outside. As shown in FIG. 1, the odorous gas 19 rises in the cover 9 and is sensed by the odor detector 22A of the odor detector 22 attached to the ceiling side, and this signal is sent to the monitoring device 23, and the bus bar 8 and It can be detected that the temperature of the joining bolt 16 is 80 ° C. or higher. In this state, it is not immediately inspected, but is included as an inspection item in the inspection plan for the next maintenance inspection day.

When the thermosensitive capsule 17B operating at 100 ° C. is operated in this state, the odor detector 22B of the odor detector 22 senses it, and the temperature rises further, and the thermosensitive capsule 17C operating at 120 ° C. operates. When the odor detection unit 22C senses it, the operation of the induction heating device is immediately stopped and checked without waiting for the check date. In this case, since the containers 18 of the temperature-sensitive capsules 17A to 17C are made of a nonmagnetic material, they are the same as the temperature of the bus bar 8 and the joining bolt 16 that are in contact with each other without being affected by the leakage magnetic flux from the heating coil 3. Therefore, the temperature can be detected with high accuracy.

Therefore, depending on which temperature capsule 17A to 17C is activated, it is not immediately inspected, but is included in the inspection plan for the next maintenance inspection day, or if the temperature rises abnormally, It is possible to immediately determine whether to stop the operation of the induction heating apparatus for inspection, and normally, since there is no rapid temperature rise, it is possible to wait until the next maintenance inspection day.

FIG. 6 shows another embodiment of the present invention, in which the power source unit 5 covered with the cover 9 is partitioned by a partition plate 24 and separated into a plurality of space portions 25. The bus bar 8 and the bus bar of each space portion 25 are separated. The temperature-sensitive capsule 17 is attached to the joining bolt 16 and an odor detector 22 for detecting odorous gas is attached to the inside of the upper space 25.

In the above apparatus, the power source unit 5 is separated into a plurality of space units 25, and the temperature-sensitive capsules 17 are attached to the bus bars 8 and the bus bar joining bolts 16, respectively. Can be checked.

In the above description, the case where a liquid is used as a substance generating odorous gas is shown, but a solid may be used.

It is a block diagram of the temperature monitoring system for induction heating apparatuses by embodiment of this invention. It is a perspective view which shows the state which attached the temperature-sensitive capsule to the bus bar and joining bolt of FIG. It is a perspective view of a temperature sensitive capsule. It is sectional drawing of the temperature-sensitive capsule shown in FIG. It is a perspective view of an odor detector. It is a block diagram of the temperature monitoring system for induction heating apparatuses by other embodiment of this invention. It is a block diagram which shows the conventional induction heating apparatus.

Explanation of symbols

1 dolly
2 Heated material
3 Heating coil
4 Inductor
5 Power supply
7 capacitors
8 Busbar
9 Cover
10 Drainage pipe
11 Cooling water hose
12 Water supply pipe
13 Flow meter
14 Thermostat
16 Joining bolt
17 Temperature-sensitive capsule
18 containers
19 Odorous gas
20 liquid
21 Solder
22 Odor detector
23 Monitoring device
24 divider
25 Space

Claims (3)

A container made of non-magnetic material contains a substance that generates odorous gas, and a temperature-sensitive capsule sealed with solder that melts at a predetermined heat-sensitive temperature is covered with a cover of the induction heating device. A temperature monitoring system for an induction heating device, which is attached to a bus bar or a joint bolt of a bus bar, an odor detector for detecting odorous gas is attached to the inside of the upper cover, and this is connected to a monitoring device. The power supply covered with the cover is separated into multiple spaces, and a temperature-sensitive capsule is attached to the bus bar of each space and / or the joint bolt of the bus bar, and odorous gas is detected inside the space above. The temperature monitoring system for an induction heating apparatus according to claim 1, wherein an odor detector is attached. 3. The induction heating according to claim 1, wherein the temperature-sensitive capsules are sealed with solder that melts at different temperatures, and contain substances that generate different types of odorous gases. Temperature monitoring system for equipment.