JPS6230535A - Stirring apparatus - Google Patents

Abstract

PURPOSE:To enhance the durability of the titled apparatus, by providing two plate shaped metal fixing members fixed to each arm mounted to a stirring shaft and having stirring blades fixed thereto and the ceramic blade main body fixed so as to be inserted and held between said fixing members. CONSTITUTION:A plurality of arms 3 are mounted to the stirring shaft 3 of a vertical sludge incinerator 1 and a plurality of stirring blades 4 are fixed to each arm 3. A ceramic blade main body 6 is inserted and held between two fixing members 5 and fixed by a positioning pin 7 and a nut 8. In this case, because the falling of the ceramic blade main body is prevented by the bent part 9 formed to the lower end of one fixing member and the ceramic blade main body is not clamped by a bolt, heat stress by mechanical clamping force and thermal expansion difference is not concentrated. In this stirring apparatus, the characteristics of ceramics are sufficiently utilized and durability is enhanced and the use temp. in the incinerator can be raised to 200 deg.C.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a sludge incinerator, an activated carbon activation furnace, etc., which is a combination of metals and ceramics, for stirring materials that are subject to heat load by combustion or thermal decomposition. Regarding a stirring device.

[Conventional technology]

Conventionally, heat-resistant and wear-resistant materials, such as heat-resistant cast steel (SCH-13), have been used for the stirring devices of such furnaces.

[Problem that the invention seeks to solve]

However, even with heat-resistant cast steel, the lifespan of objects that are subject to high temperature and abrasion is about 6 months due to heat load. Furthermore, the lifespan of modern furnaces is becoming shorter and shorter due to the adverse conditions of atmospheric gas usage.

[Means for solving problems]

As a result of repeated research by the present inventors to solve the above drawbacks,
By combining metal and ceramics and creating a simple shape that takes advantage of the features of both, we succeeded in further improving durability and completed the present invention.

That is, the present invention provides a stirring device that is subject to a heat load due to combustion or thermal decomposition of a stirred material, and includes two metal plate-shaped fixing members in which stirring blades are fixed to arms attached to a stirring shaft;
This stirring device is characterized by comprising a ceramic blade body that is fitted and fixed between the fixing members.

The ceramics constituting the blade body used in the present invention are oxide and non-oxidizing ceramics and generally have a heat resistance temperature of 1000
Examples include ceramics that have good wear resistance at temperatures above ℃. Specifically, alumina, silicon nitride, silicon carbide, sialon,
Zirconia etc.

Further, metals used as the fixing member include metals having a heat resistance of 1000° C. or higher, such as heat-resistant cast steel and stainless steel.

To obtain the stirring blade of the present invention, an upper metal plate-shaped fixing member fixed to an arm attached to the stirring shaft and a lower blade body made of ceramic are combined.

In this case, by providing a sufficient gap between the two and adopting a simple shape, damage and falling off due to differences in thermal expansion can be prevented.

〔Example〕

Each embodiment of the stirring device of the present invention will be explained below with reference to the drawings.

FIG. 1 is a sectional view of a vertical sludge incinerator 1, in which a plurality of arms 3 are attached to a stirring shaft 2, and each arm has a plurality of stirring blades 4.
is fixed.

FIGS. 2 and 3 are examples of stirring blades.

FIG. 2 is a front view of the stirring blade, and FIG. 3 is an enlarged sectional view of the portion where the ceramic blade main body 6 is fixed to the metal plate-shaped fixing member 5. That is, the ceramic wing main body 6 is fitted and held between the two fixing members 5, and is fixed with a positioning pin 7 and a nut 8. In this example, the bent portion 9 at the lower end of one fixing member prevents the ceramic wing body from falling, and since the ceramic is not directly tightened with bolts, mechanical tightening does not concentrate thermal stress due to force and thermal expansion difference.

The next embodiments are shown in FIGS. 4 and 5. FIG. 4 is a front view of the stirring blade, and FIG. 5 is an enlarged sectional view of the portion where the ceramic blade main body 6 is fixed to the metal plate-shaped fixing member 5. That is, the ceramic wing main body 6 is fitted and held between the two fixing members 5, and is held and fixed by a plurality of (two in FIGS. 4 and 5) poles 10 and nuts 11. In this case, the through-hole portion of the ceramic blade body has sufficient clearance to prevent concentration of thermal stress.

The next embodiment is shown in FIGS. 6 to 8. FIG. 6 is a front view of the stirring blade, and FIG. 7 is an enlarged sectional view of the portion where the ceramic blade main body 6 is fixed to the metal plate-shaped fixing member 5. FIG. 8 is a perspective view showing how the ceramic wing body 6 is fixed by providing the bent portion 9 at the lower end of one metal fixing member and the stopper 20 when the ceramic wing body 6 is fitted and held. That is, in FIG. 8, the ceramic wing main body 6 is inserted between two metal plate-shaped fixing members as shown by the arrow, and the stopper surface 21 of one of the fixing members and the protrusion 24 of the ceramic wing main body are connected. The surfaces 22 meet and cannot advance any further, and the protrusion 24 itself rests on the surface 23 formed by the bent portion 9 at the lower end of one of the fixing members and is stabilized. As a result, it is fixed stationary with a cross section as shown in FIG. Even when centrifugal force is applied during stirring, no movement occurs between surfaces 21 and 22, and since there are no tightening sections, thermal stress is not concentrated.

What has been described above is merely a representative example of the present invention, and the ceramic wing body is fitted and clamped between two metal plate-shaped fixing members with a simple shape and structure, and fixed by some method. If possible, a structure other than these examples may be used, and the structure is not limited.

〔Effect of the invention〕

The present invention uses a combination of a metal plate-shaped fixing member and a ceramic wing main body, which greatly simplifies the shape and structure, makes full use of the characteristics of ceramics, improves durability, and improves durability compared to conventional A single stirring blade made of heat-resistant cast steel has a lifespan more than twice as long compared to other blades, and the operating temperature inside the furnace can be increased by 200°C.

Furthermore, when replacement is required due to wear and tear, the ceramic blade main body can be replaced, and it is extremely easy to attach and detach, and together with its longevity, it is also very economical.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of the vertical sludge incinerator, and Figures 2 to 8
The figures show examples of the stirring blades of the present invention, and Figs.
The figure shows one example, and FIG. 2 is a front view, and FIG. 3 is an enlarged view of the fixed part ((a) is a sectional view, (b) is a front view).
Figures 4 and 5 show another embodiment, with Figure 4 being a front view and Figure 5 being a front view.
The figure is an enlarged sectional view of the part to be fixed, and Figures 6 to 8
The drawings show still another embodiment; FIG. 6 is a front view, FIG. 7 is an enlarged sectional view of the portion to be fixed, and FIG. 8 is a perspective view showing the state of fixation. FIG. 9 shows a front view of a conventional stirring blade made of a single sheet of heat-resistant cast steel. 1... Furnace 2... Stirring shaft 3.
... Arm 4 ... Stirring blade 5.
...Metal plate-shaped fixing member 6...Ceramic wing body 7...Positioning bin 8.11...Nut 9...Fixing member Lower end bent portion 10... Bolt 20... Stopper 21.22.23...
...Surface 24...Protruding portion Patent applicant Nippon Cement Co., Ltd. Fuji Rozai Co., Ltd.

Claims (1)

[Claims] In a stirring device that is subjected to a heat load due to combustion or thermal decomposition of the material to be stirred, a stirring blade is fitted between two metal plate-shaped fixing members fixed to an arm attached to a stirring shaft and the fixing member is clamped. A stirring device characterized in that it consists of a ceramic blade body and a fixed ceramic blade body.