JPS6138993B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] The present invention is an apparatus for observing the internal conditions of various types of kilns during hot conditions, and is mainly used for observing the damage state of refractories used in the furnaces during hot conditions. This relates to a device for

[Prior art and its problems]

Generally, the inside of a kiln in use is at a high temperature, so it is extremely difficult to observe the inside of the furnace and understand the extent of damage.
Therefore, when observing the inside of the furnace, it is common to turn off the fire, cool it down to room temperature, and then observe the damage inside the furnace to decide whether to continue using it or repair it. However, shutting down the furnace in order to observe damage inside the furnace during operation causes extremely large operational heat losses and production losses, so efforts are made to avoid shutting down the furnace as much as possible. However, observation of the inside of the furnace is necessary, and currently it is relatively often used to measure the shell temperature, measure dimensions using laser light, or measure by embedding a temperature sensor or using ultrasonic waves. There is. However, all of the above methods are indirect observation methods, and it is impossible to check the damage state in detail. For this reason, there is an increasing need for direct hot observation.

Recently, a water-cooled box-type furnace observation device for pig iron mixers that houses a television camera has been developed in response to the above request, and has achieved good results (published in "Refractories" 33-201 No. 4.1981). . In this method, a commercially available color television camera is housed in a strong insulated box, and the inside of the insulated box is cooled with water. I hung it from the pedestal and moved the pig iron mixer car under the pedestal.
It is lowered from the top to the bottom using a power transfer device and inserted into the furnace for observation. A television camera placed in an insulated box observes the furnace wall through a quartz glass window. This method is a very good method for directly observing the inside of the furnace, and the observation results are also excellent in judging.

However, this method also has the following major problems. Because the TV camera is inserted into a high-temperature zone of 1,000 degrees Celsius or more, it is necessary to provide heat protection, so an insulated box with water cooling is required, but this equipment is extremely large and expensive to manufacture, and is fixed. In this case, the method of use is limited and it becomes impossible to use it in various furnaces. Another disadvantage is that the heat-resistant glass for the observation window is easily damaged at high temperatures of 1200°C or higher.

It is desirable that such an apparatus be mobile and handy, and that it be able to be inserted into the high-temperature zone for observation even through a very small opening. Therefore, unless it is small and easily portable, it has low utility value. Considering these conditions, there is currently no product that satisfies this requirement.

[Structure and operation of the invention]

The present invention has been made to solve the above problems, and provides a device that is lightweight, small, and capable of long-term observation at temperatures ranging from room temperature to 1500°C.

The gist of the present invention is to provide a cooling box having a water-cooled jacket, a support rod containing a cooling water supply/discharge pipe and a cooling air conduit at one end of the cooling box, and an observation rod at the other end of the cooling box. A circular window is provided, a quartz glass assembly attached to a cooling air fitting is disposed inside the circular window by at least 1/2 of its diameter, and a large number of small holes through which cooling air is ejected onto the surface of the quartz glass is provided. The present invention relates to an in-furnace observation device that is installed in an air hardware and has a television camera built into a cooling box.

Hereinafter, an example of the apparatus according to the present invention will be specifically described based on the cross-sectional front view of the furnace interior observation apparatus shown in FIG.

The in-furnace observation device consists of a cooling box 2 containing a television camera 1 and a support rod 3.
The cooling box 2 is inserted into the high temperature part of the furnace. The support rod 3 contains cooling water 4, cooling air 5, and television camera control leads (not shown).

The cooling box 2 has two layers of cooling water 4, and has a structure in which cold water enters from the inner layer 6 and flows to the outer layer 7 to enhance the cooling effect. The material for the cooling box 2 was copper, with an emphasis on thermal conductivity in order to minimize the temperature rise in the housing section of the TV camera 1. good. Stainless steel, which is easy to process by welding, is generally used as the material for this type of cooling box 2 for observing the inside of a high-temperature furnace, but the thermal conductivity of stainless steel is less than one-tenth that of copper.
It is not possible to sufficiently cool parts such as the cooling box 2 of the present invention where the cooling water 4 cannot flow directly due to the structure. On the other hand, since copper has a high thermal conductivity, the temperature of the parts through which the cooling water cannot directly pass and the parts through which the cooling water 4 flows can be kept at almost the same temperature, which is very effective in keeping the entire cooling box 2 at the same temperature. This effect is particularly apparent at the opening of the observation window, and is highly effective in preventing the temperature rise inside the cooling box 2 due to radiant heat. However, with this alone, it is difficult to maintain the temperature inside the cooling box 2 at a temperature that will not damage the television camera 1 when observing the inside of the high-temperature furnace at 1500°C. Therefore, in order to prevent the radiant heat from the circular observation window 8 and to protect the quartz glass 9 from heat, the observation window 8 was moved to the back of the cooling box 2 by at least 1/2 of the dimension D of the window opening. The cooling of the observation window 8 is strengthened by a structure in which the observation optical path is narrowed. If it is inserted too deep, the field of view will be narrowed, and if it is too shallow, the cooling effect will be lost, so it should be 1/1/1 of the dimension D of the observation window 8 opening.
It is preferable that it is 2-1. In addition, the quartz glass 9 for the observation window is constructed of two sheets and is installed with a gap of 5 to 30 mm between the quartz glasses 9, so that the inside can be ventilated, so that the radiant heat is reflected by the surface of each quartz glass. This prevents the liquid from entering the cooling box 2. As a cooling method, in addition to water cooling, it is also possible to use a method in which cooling air 5 is blown from the outside into the television camera 1 housing portion of the cooling box 2 via the support rod 3 to directly cool the television camera 1. The cooling air 5 that has entered the cooling box 2 is blown out toward the center through a number of small holes drilled in the mounting hardware 10 around the quartz glass 9 for the observation window to cool the surface of the quartz glass 9, and the openings of the observation window 8 are used to cool the cooling air. 5 and prevents radiant heat from the observation window 8. The larger the amount of cooling air 5 fed into the cooling box 2, the greater the cooling effect, but if the amount is too large, the pressure inside the cooling box 2 will rise, so there is a limit depending on the withstand pressure of the television camera 1. For this reason, in order to achieve a large cooling effect with the minimum necessary amount of cooling air 5, it is extremely effective to reduce the cross-sectional area of the opening of the observation window 8 and increase the flow rate of the cooling air 5. be.

The in-furnace observation device of the present invention includes cooling water 4 and cooling air 5.
The temperature inside cooling box 2 is measured by TV camera 1.
If either the cooling water 4 or the cooling air 5 stops, the expensive TV camera 1 will be damaged, so the cooling box 2
It is also possible to provide a device that issues an alarm using a sensor attached to the television camera 1 when the internal temperature rises. FIG. 2 shows the temperature distribution inside the cooling box 2 of the present invention when observing the inside of the furnace at 1500°C in a direct view state.

〔Effect of the invention〕

The effects of the present invention are as follows.

Extremely small and lightweight compared to conventional products and can withstand temperatures of 1500℃
It has become possible to observe the inside of various furnaces at high temperatures. Furthermore, the water-cooled box 2 that houses the television camera 1 can be made as small as 155 mm, and can be inserted through a 160 mm temperature monitoring hole to observe the inside. Therefore, when this device is used, it is no longer necessary to shut off the fire, which has been a hindrance to operations, to determine whether or not continued use is possible, and there is no longer any hindrance to production.

Furthermore, it is possible to schedule the repair of furnace materials during use, and the repair materials can be prepared without wasting them, which is extremely effective.

[Brief explanation of the drawing]

1 and 2 are cross-sectional front views of the furnace observation device of the present invention, and FIG. 3 is a detailed view of the quartz glass part for the window.
In the figure, 1... TV camera, 2... Cooling box, 3... Support rod, 4... Cooling water, 5... Cooling air, 6... Cooling water inner layer, 7... Cooling water outer layer,
8... Circular window for observation, 9... Quartz glass for windows, 1
0... Cooling air hardware attached to quartz glass for windows.

Claims (1)

[Claims] 1. A cooling box having a water cooling jacket, a support rod containing a cooling water supply/discharge pipe and a cooling air conduit at one end of the cooling box, and a circular observation window provided at the other end of the cooling box, A quartz glass assembly attached to a cooling air fitting is disposed inwardly at least 1/2 of the diameter of the circular window, and a large number of small holes are provided in the cooling air fitting for blowing out cooling air onto the surface of the quartz glass. An in-furnace observation device characterized by: and a television camera built into the cooling box.