JPS5927769A - Heat insulating device of molten metal - Google Patents

Abstract

PURPOSE:To improve the thermal efficiency in the heat insulation of molten metal and to decrease the oxidation of the molten metal by forming through- holes respectively in the opposite positions of the side walls of a vessel for heat insulating the molten metal, inserting pipes contg. heating elements into the through-holes and fixing the pipes to the side walls. CONSTITUTION:A vessel 10 made of cast iron is installed in a furnace wall 11, and ceramic fibers 6 are packed between the same. The 1st, the 2nd through- holes 22, 23 are respectively provided in the opposite positions of the side walls 10a of the vessel 10, and pipes 13 are inserted thereon. Heating elements 14 are installed in the pipes 13 to insulate the heat of molten metal 7. The upper part of the vessel 10 except a gooseneck 1 is covered with split covers 15. The pipe 13 is fixed to the side wall 10a by means of the flange part 13a of the pipe 13 and the 1st lock nut 19 on the hole 22 side and the pipe 13 is fixed to the side wall 10a by means of the 2nd lock nut 20 and the 3rd lock nut 21 on the hole 23 side. The peripheries of the holes 22, 23 are thoroughly sealed with packings 16 having excellent heat resistance and stretchability.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a molten metal warming device used for melting or keeping metal such as zinc warm.

Conventional molten metal heat retention devices obtain a predetermined temperature of 420 to 450° C. (temperatures are taken for zinc as an example, and the same applies hereinafter) using an external indirect heating method.

FIGS. 1 and 2 are cross-sectional views of a conventional molten metal heat retention device.

Conventional molten metal heat retention devices heat the bottom of the cast iron container 2 with a gas burner 4 (Fig. 1), or heat the periphery of the cast iron container 2 with a nichrome wire 5 or a nonmetallic heating element. : (Figure 2). In addition, 1 indicates a gooseneck, and 3 indicates an insulating refractory brick.

Conventional molten metal heat retention devices are of the external indirect heating type, and therefore have the following drawbacks.

(1) The ambient temperature of the 4Ii iron container 2 is 100 to 200℃
It is even more dangerous.

(2) In the external indirect heating method, it is necessary to raise the temperature of the gas burner 4 and the nichrome wire 5, which oxidizes the cast iron container 2 and has a short life of about one year.

(3) Low thermal efficiency of 10-20% and high fuel efficiency.

(4) Due to the external indirect heating method, there is a time lag in regulating the hot water temperature, resulting in an error of ±20°C in culm with respect to the set temperature.

(5) The temperature of the molten metal immediately above the gas burner 4 and the nichrome wire 5 is as high as 600 to 700°C, and oxidation is severe.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a molten metal heat retention device that has good thermal efficiency and less oxidation of the molten metal.

In the molten metal heat retention device of the present invention, a first R through hole and a second through hole are formed at opposite positions on the side wall of a cast iron container, and a pipe having a flange formed at one end is inserted into the first through hole and the second through hole. The flange and the first clamping member are used to sandwich the side wall on the first through hole side, and at the same time, the second clamping member and the third clamping member are used to sandwich the side wall on the second through hole side. Then, the pipe is fixed to the side wall, the periphery of the first through hole and the second through hole is sealed with a backing having excellent heat resistance and elasticity, and the side wall and bottom of the TLI iron container are covered with ceramic fiber. The structure is such that metal is placed in the cast iron container and the metal is melted and kept warm.

Since the molten metal heat retention device of the present invention is configured as described above, the temperature of the furnace wall is as low as about 60° C. or less. When metal is melted or kept warm using the molten metal heat retention device of the present invention, the temperature of the cast iron container is lower than that of the conventional method. Therefore, the cast iron container used in the molten metal heat retention device of the present invention is less likely to be oxidized. Since the molten metal heat retention device of the present invention uses direct heating, it has good thermal efficiency.
% or more. Further, the molten metal heat retention device of the present invention has no time rack and can adjust the temperature within ±5°C. Since the molten metal heat retention device of the present invention has good thermal efficiency as described above,
There is no need to heat the heating element too high.

Therefore, there is less oxidation of the molten metal. Furthermore, since the furnace walls do not reach high temperatures, the working environment can be improved.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

FIG. 3 is a sectional view showing an example of the molten metal heat retention device of the present invention.

A cast iron container 10 is installed within a furnace wall 11. Molten metal 7 is put into a casting container 10.

A first through hole 22 and a second through hole 23 are formed at opposing positions in the side wall 10a of the cast iron container 10. The first through hole 22 is larger than the second through hole 23. First through hole 2
2 and the pipe 13 is inserted into the second shell through hole 23. The pipe 13 is made of stainless steel or cast iron, for example. A heating element 14 is installed inside the pipe 13.

As the heating element 14, for example, a non-metallic heating element such as a metal wire or a heating element made of monocarbon carbide is used. Both ends of the heating element 14 are connected to a power source (not shown).

Furnace v! The inside of 11 is hollow. Cast iron container 10
Ceramic fibers 6 are filled between the furnace wall 11 and the furnace wall 11 . The thickness of ceramic fiber 6 is approximately 100~
It is 200mn+. The upper part of the cast iron container 10 is covered with a divided lid 15 made of ceramic fiber except for the gooseneck 1 to prevent heat dissipation and air inflow.

FIG. 4 is a partial view showing an example of the fixed portion of the covering pipe used in the present invention.

Seven flanges 13a are formed at one end of the pipe 13. An intermediate portion 13f continues from the flange 1'3a. Middle part 1
The length of 3f is approximately equal to the width of the cast iron container 10. A threaded portion 13C is formed in the intermediate portion 13f. Threaded part 13
The distance between C and the flange 13a is approximately equal to the thickness of the side wall 10a. A distal end portion 13b is formed following the intermediate portion 13[. A threaded portion 13d is formed at the end of the intermediate portion 13f1 on the distal end portion 13b side. A spring 130 is formed at the tip of the tip portion 13b. The tip portion 131] is formed thinner than the intermediate portion 13f. The through hole 22 is
The diameter of the intermediate portion 13f is a through hole that is slightly larger, and the through hole 23 is an n-through hole that is slightly larger than the diameter of the tip portion 13b.

In the embodiment shown in FIG. 4, all the tightening members are nuts. The first tightening nut 19 engages with the threaded portion 13C, and the flange 13a and the first tightening nut 19 sandwich the side wall 10a on the first through hole 22 side. During the second tightening (nonanes 1 to 20 are engaged with the threaded portion 13d, and during the third tightening, the nuts 1 to 21 are engaged with the threaded portion 13e), and during the second tightening, the nuts 20 and the third tightening ( Second with Punat 21
The side wall 10a on the side of the through hole 23 is sandwiched. Thus pipe 13
is fixed to a cast iron container 10.

The peripheries of the first circular through hole 22 and the second through hole 23 are completely sealed with a backing 16 having excellent heat resistance and elasticity. The backing 16 on the inside of the cast iron container 10 is made of, for example, graphite paper. The backing 16 on the outside of the cast iron container 10 is made of, for example, a ceramic fiber sheet or graphite paper.

Between the heating element 14 and the pipes 1 and 3, there is a leakage prevention filler 1
8) is true. Leakage prevention filler 18 is pipe 1
Filled in near both ends of 3? Ill.

In the embodiment shown in FIG. 4, 1 g of the leakage prevention filler material 18 was filled at a distance of 5 Qmm from both ends of the pipe 13. As the leakage prevention filler 18, for example, mortar made of ceramic twill is used. Leakage prevention filler 18 is pipe 13
This is to prevent molten metal from leaking when the pipe is damaged.

The heating element 1/I is attached to the insulating sleeve 26 (pipe 13
is held at the center of the Terminals 27 are installed at both ends of the heating element 14 and are connected to the C1 power source. Further, both ends of the heating element 1/I are filled with heating element end fillers 17.

The heating element end filling material 17 is aged in a jil, less 'l'
;b,.

As the heating element end filling material '17, No. 1, for example, mortar made of lamic fiber is used.

A molten metal leak detector 28 is installed in a place where a molten metal leak can be detected immediately, for example, between the first f1 through hole 22 and second shell through hole 23 and the pipe 13, and between the insulating sleeve 26 and the leak prevention filler 18. It's very convenient.

FIG. 5 is a partial view showing another example of the vibrator fixing part used in the present invention.

In the embodiment shown in FIG. 5, unlike the embodiment shown in FIG. 4, a threaded portion is not formed at the end of the vibrator intermediate portion 24 [on the distal end portion 24g side]. Then, for the second tightening, instead of the nut 20, the sluss 1 to the curler 25 tighten the backing 16 once.

Slash 1 to curler 25 are pushed by intermediate thrust surface 24g. The fixing portion on the first through hole 22 side is the same as the embodiment shown in FIG. 4.

[Brief explanation of drawings]

Figures 1 and 2 are cross-sectional views showing an example of a conventional molten metal warming device, Figure 3 is a cross-sectional view showing an example of a molten metal moisturizing device of the present invention, and Figure 4 is a sectional view of a pipe used in the present invention. FIG. 5 is a partial view showing another example of the fixed part of the layered pipe used in the present invention. 10...Cast iron container 11...Furnace wall 13...Pipe 14...Light heating element 15...Divided lid 16...Backing 17...Heating element end filler 18...Leakage Prevention filler 1 1...1st tightening 4J nut 1~20...2nd tightening [Pnut 21...3rd tightening nut 1~22...10th through hole 23. ...Second shell hole 24...Pipe 25...Thrust curler 26...Insulating sleeve 27...Terminal 28...Molten metal leak detector Patent applicant Toshiba Ceramics Corporation and one other person Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a molten metal heat retention device for melting and keeping the metal warm by placing the metal in a cast iron container, a first through hole and a second through hole are formed at opposing positions on a side wall of the cast iron container, and a flange is provided at one end. The formed pipe is inserted into the first shell through hole and the second shell through hole.
inserted into the through hole, the seventh flange and the first tightening member are used to sandwich the side wall on the first shell through hole side, and at the same time, the second tightening member and the third tightening member are used to sandwich the side wall on the second nth through hole side. The said side wall of lυ
The pipe is fixed to the side wall, the periphery of the first through hole and the second through hole is sealed with a backing having excellent heat resistance and elasticity, and the side wall and bottom of the cast iron container are fixed with Relamic 7I rubber. A molten metal heat retention device characterized by having a covering configuration.