JPH09201U - Lining structure of ultra-high temperature resistance furnace - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide a lining structure of an ultra-high temperature resistance furnace capable of stably withstanding even an atmosphere temperature in the furnace exceeding 1800 ° C. SOLUTION: Each corner of a heat insulating material arranged on a ceiling, a wall and a floor of an ultrahigh temperature heating chamber is connected with a fastener made of ceramics,
For example, it is characterized in that it is connected by using a ceramic pin or a ceramic shaving to prevent a joint opening due to expansion / contraction or sintering contraction.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention is an ultra-high temperature resistance furnace using a zirconia heating element that is used for quality evaluation tests such as melting of high melting point oxides, crystal growth and heat treatment (annealing), sintering or compression, bending, and tensile tests. In particular, the present invention relates to a lining structure of an ultra-high temperature resistance furnace having an ultra-high temperature heating chamber in a preheating (heating) chamber of the ultra-high temperature resistance furnace.

[0002]

[Prior art]

 Conventionally, as a high temperature heating element used in an oxidizing atmosphere, silicon carbide has been used up to about 1400 ° C, and molybdenum disilicide up to about 1700 ° C. Further, lanthanum chromite is used as a heating element having a higher temperature than this, and zirconia heating element is used as a heating element for ultrahigh temperature.

FIG. 3 is a diagram showing an example of an ultra-high temperature resistance furnace using an ultra-high temperature heating element. FIG. 3 (a) is a longitudinal sectional view and FIG. 3 (b) is AA of FIG. 3 (a). FIG. The ultra-high temperature resistance furnace 20 has a structure in which a pre-heating / heating chamber 21 formed of an alumina fiber board 27 is provided with an ultra-high temperature heating chamber 22 formed of a zirconia halo board 26 and a lifting hearth 28. . The ultra-high temperature heating chamber is placed on the elevating hearth 28 and moved up and down to move it into and out of the furnace. A furnace door 30 is provided on the front side to move the sintered body into and out of the furnace. . The preheating / retaining greenhouse 21 is heated to a high temperature by the molybdenum disilicide heating element 23 and heats the zirconia heating element 24 inserted into the ultrahigh temperature heating chamber through the insulating ring 25, and the zirconia heating element is conductive at high temperature. When the power is turned on, heat is generated and an ultrahigh temperature state of 1800 ° C. or higher is achieved. The temperature inside the furnace can be measured with a radiation thermometer 29.

[0004]

[Problems to be solved by the device]

 By the way, it has not been possible to obtain a lining structure that can stably withstand the ultrahigh temperature even when the temperature of the atmosphere in the furnace is increased to over 1800 ° C. by using a zirconia heating element. This is because cracking or opening of joints occurs in the heat insulating material due to repeated expansion and contraction or sintering and contraction that accompany heating and cooling to ultra-high temperatures. The present invention is intended to solve the above problems, and an object thereof is to provide a lining structure of an ultra-high temperature resistance furnace that can stably withstand a furnace atmosphere temperature exceeding 1,800 ° C by using a zirconia heating element or the like. And

[0005]

[Means for Solving the Problems]

 According to the present invention, each corner of the heat insulating material arranged on the ceiling, wall and floor of the ultra-high temperature heating chamber is connected by using a fastener made of ceramics, for example, a ceramic pin or a ceramic “glazing” to expand or contract or burn. The feature is that it prevents the joint from opening due to shrinkage. The ultra-high temperature resistance furnace of the present invention has a heating temperature of 1900 ° C or higher in the air atmosphere, and each corner of the heat insulating material installed on the ceiling, wall and floor of the ultra-high temperature heating chamber is attached with ceramic fasteners. By fastening, the generation of cracks due to the action of thermal stress or the cracks due to sintering shrinkage can be prevented, and a lining structure that can withstand extremely high temperatures of 1800 ° C or higher can be obtained. However, interposing a zirconia-based material and an alumina-based lining material (heat insulating material) at a working temperature of 1770 to 1780 ° C. is not preferable because they react with each other to form a low melt.

[0006]

[Embodiment of the invention]

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a view showing an example of an embodiment of an ultrahigh temperature resistance furnace according to the present invention, FIG. 1 (a) is a front view, and FIG. 1 (b) is a side sectional view of FIG. 1 (a). In the figure, 1 is a super high temperature resistance furnace, 2 is a preheating / retaining greenhouse, 3 is a super high temperature heating chamber, 7 is a zirconia board, 9 is a zirconia heat generator, 12 is a zirconia board, 13 is an alumina fiber board, and 14 is a zirconium. It is Koniapin.

In the ultra-high temperature resistance furnace 1, an ultra-high temperature heating chamber 3 is formed by enclosing the zirconia boards 7 and 12 in a preheating / greenhouse 2 enclosed by an alumina fiber board 13. In the preheating / greenhouse 2, a plurality of molybdenum disilicide heating elements (not shown) are arranged as high temperature resistance heating elements. Further, in the ultra-high temperature heating chamber 3, a plurality of zirconia heating elements 9 are provided as ultra-high temperature resistance heating elements through a magnesia tube (not shown) that prevents leakage due to contact with the zirconia board. The corners of the heat insulating material are connected using zirconia pins 14 through the ceiling, walls and floor of the ultra-high temperature heating chamber configured as described above. With such a structure, it was possible to prevent the joint opening of the lining material due to expansion and contraction or sintering and contraction.

FIG. 2 is a view showing another example of the embodiment of the ultra-high temperature resistance furnace according to the present invention, FIG. 2 (a) is a front view, and FIG. 2 (b) is a side view of FIG. 2 (a). The same numbers as in FIG. 1 indicate the same contents. In addition, 15 is a zirconia "glare".

In this example, the heat insulating materials provided on the ceiling, wall and floor of the ultra-high temperature heating chamber are connected by "glazing" made of zirconia, and the other configurations are the same as those in FIG. Is. With such a structure, expansion of the lining material due to expansion and contraction or sintering and contraction could be prevented.

Although the zirconia boards 7 and 12 are used in the examples of FIGS. 1 and 2, it is also possible to apply zirconia halo boards containing zirconia fibers instead of the zirconia boards.

[0011]

[Effect of the invention]

 As described above, by adopting the lining structure according to the present invention in the ultra-high temperature heating chamber of the ultra-high temperature resistance furnace, the thermal insulation material (lining material) installed on the ceiling, wall and floor expands and contracts or burns during heating and cooling. The joint opening due to binding shrinkage has disappeared, the ambient temperature inside the ultra-high temperature heating chamber has stabilized, and a lining structure has been obtained that can withstand the ultra-high temperature of 1900 ℃.

[Brief description of the drawings]

FIG. 1 is a view showing an ultra-high temperature resistance furnace according to an embodiment of the present invention.

FIG. 2 is a view showing another embodiment of the present invention.

FIG. 3 is a diagram for explaining the structure of a conventional ultra-high temperature resistance furnace.

[Explanation of symbols]

1 ... Ultra high temperature resistance furnace, 2 ... Preheating / retaining greenhouse, 3 ... Ultra high temperature heating chamber, 7 ... Zirconia board, 9 ... Zirconia heating element, 1
2 ... Zirconia board, 13 ... Alumina fiber board, 14 ... Zirconia pin, 15 ... Zirconia "glazing".

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location F27D 11/02 F27D 11/02 B

Claims (3)

[Utility model registration claims] 1. An ultra-high temperature heating chamber which is surrounded by a high-temperature heat insulating material and is heated by an ultra-high-temperature resistance heating element under an oxidizing atmosphere in a preheating / retaining greenhouse which is heated by a high-temperature resistance heating element and in which an object to be heated is placed. A lining structure for an ultra-high temperature resistance furnace, characterized in that, in the ultra-high temperature resistance furnace having the above, the heat insulating materials arranged on the ceiling, wall and floor of the ultra-high temperature heating chamber are connected by using fasteners made of ceramics. 2. The lining of an ultra-high temperature resistance furnace according to claim 1, wherein the fastener comprises a zirconia pin connecting each corner of the heat insulating material through the ceiling, wall and floor of the ultra-high temperature heating chamber. Construction. 3. The ultra-high temperature resistance furnace according to claim 1, wherein the fastener comprises a zirconia braze that connects heat insulating materials arranged on the ceiling, walls and floor of the ultra-high temperature heating chamber. Lining structure.