JP3499718B2 - Rotary kiln - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to calcination of a metal raw material.
The present invention relates to an indirect heating type rotary kiln used for firing / oxidation of metal powder, reduction of metal raw materials, treatment of earth and sand containing organic substances, and the like.

[0002]

2. Description of the Related Art Conventionally, as an indirect heating type rotary kiln 40 of this kind, as shown in FIGS. 11 and 12, both ends 42 and 43 of a furnace core tube 41 made of metal are externally fitted to a metal. The tires 44 and 45 are rotatably supported via a pair of rollers 46 and 46, respectively, and a combustion chamber 47 is formed on the outer periphery of the furnace core tube 41 between the tires 44 and 45. The oil is burned by the burner 48 into the combustion chamber 4
The material burned in the furnace 7 and supplied to the furnace core tube 41 is processed.

Incidentally, 49 is an exhaust pipe, 50 is an exhaust collecting pipe,
Reference numeral 51 is an exhaust blower. As a method of attaching the tires 44, 45 to the furnace core tube 41, as shown in FIGS. 13 and 14, a method of directly welding the ring-shaped tire 44 to the furnace core tube 41, and FIGS. 15 and 16 are shown. So that the furnace core tube 4
A method of welding a large number of getters 52 to the outer circumference of one, and a tire 44 on the getters 52, and further, as shown in FIG. 17, the getters 52 are welded to the furnace core tube 41, and the tires 44 are attached to the outer circumference thereof. After fitting, a method is used in which the slip prevention guides 53 are welded to both sides of each getter 52 and the tire 44 in the axial direction.

Further, when the rotary kiln 40 is used in a high temperature range of 800 ° C. or higher, the total length of the kiln is determined within the allowable range of hot bending of the furnace core tube 41 between the fulcrums, and it is necessary to manufacture the long axis kiln. There was a limit.

[0005]

By the way, in order to obtain a large-scale rotary kiln equipped with a long-axis furnace core tube having a larger diameter than the conventional one, which is used in a high temperature range of 800 ° C. or higher, It is necessary to support the entire furnace core tube at three or more points in order to keep the hot deflection between the fulcrums within an allowable range.

When the furnace core tube is supported at three points, the intermediate support portion of the furnace core tube has a higher temperature range than the support portions provided at both ends of the furnace core tube, so that the tire is rotatably supported. It is indispensable to take measures against the heat of the rollers and roller bearings,
Further, there is a problem in that the tire disposed at the intermediate support portion needs to have a structure that can be easily replaced without removing the tires at both ends of the furnace core tube.

The present invention has been made in view of the above situation, and an object of the present invention is to provide an unprecedented large diameter having a structure for taking measures against heat of an intermediate supporting portion and for easily replacing a tire. To provide a large indirect rotary kiln that uses a long-axis furnace core tube.

[0008]

In order to achieve the above object, the present invention takes the following technical means. That is, in the present invention, at least both ends of the metal core tube are rotatably supported by rollers via metal tires fitted to the metal core tube, and a combustion chamber is formed on the outer periphery of the core tube between the tires. In the indirect heating type rotary kiln, characterized in that a tire is externally fitted to an intermediate portion of the furnace core tube via a getter and a detachable spacer, and the tire is rotatably supported by rollers. There is.

In this case, since the spacer is present between the furnace core tube in the high temperature region of the intermediate support portion and the roller supporting the same, a sufficient distance can be secured, and therefore,
The radiant heat from the furnace core tube that the roller and the roller bearing receive is reduced, and the thermal effect is mitigated. The diameter between the getter and the spacer and between the spacer and the tire is 2 in diameter.
By providing a gap of about 7 mm, the conduction heat received by the roller can be reduced.

Further, according to the present invention, since the spacer is divided in the circumferential direction or the axial direction, or in the circumferential direction and the axial direction, the assembling / disassembling is facilitated and the tire exchanging work is facilitated. -Since the spacer and the tire are independent parts, it is possible to select materials that take heat resistance, mechanical strength, abrasion resistance, etc. into consideration when manufacturing each part.

According to the present invention, since the inner diameter of the tire in the middle portion is made larger than the outer diameter of the tire in both end portions of the furnace core tube, the spacers should be removed when replacing the tire in the intermediate supporting portion. Thus, the tires at both ends of the furnace core tube can be overridden by the tires at the intermediate portion, and therefore the tires at the intermediate portion can be easily replaced without removing the tires at the end portions.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show a first embodiment of an indirect heating type three-point supporting rotary kiln 1 according to the present invention. This rotary kiln 1 has a long-axis metal furnace core tube 2 and metal tires 3, 4, which are replaceably fitted to both ends 2A, 2B and an intermediate part 2C of the furnace core tube 2.
5, the pedestal 6, and the tire 3 arranged on the pedestal 6
Roller bearing bases 8, 9 and 1 respectively provided with two rollers 7A and 7B that rotatably support the furnace core tube 2 via
0, the combustion chamber casings 11 and 12 surrounding the outer periphery of the furnace core pipe 2 between the tires 3 to 5, the exhaust pipes 13 and 14 and the exhaust collecting pipe 15, which are connected to the upper portions of the casings 11 and 12.
16, a burner 17, 18 and an exhaust blower 19 are mainly included.

The mounting structure of the tires 3 and 4 provided on both ends 2A and 2B of the furnace core tube 2 is shown in FIGS.
Any of the conventional structures shown in 7 can be employed. And
The tire 5 supporting the intermediate portion 2C of the furnace core tube 2 is shown in FIG.
As shown in FIG. 5, a ring-shaped spacer 2 is attached to the getter 20 welded to the outer periphery of the intermediate portion 2C at equal intervals in the circumferential direction.
It is removably fitted on the outer surface 1 through 1. The inner diameter of the tire 5 is made larger than the outer diameter of the tires 3 and 4 so that the tires 3 and 4 of the both ends 2A and 2B can be overcome.

Spacer shift prevention guides 22 are welded to the getters 20 on both sides of the spacer 21 in the axial direction of the furnace core tube 2. The spacer 21 is
Flange portions 2 for positioning tires on the outer circumferences at both ends in the axial direction
Six pieces 21A, 21B, 21 obtained by dividing the ring having 3, 23 into three in the circumferential direction and two in the axial direction.
C and a plurality of sets of connecting bolts 24 and nuts 25 that respectively connect the pieces 21A to 21C in the axial direction, so that they can be disassembled. The respective pieces 21A to 21C of the spacer 21 are, as shown in FIG.
Each has a different size, and the division angle is 180 for piece 21A.
The piece 21B is set to 120 degrees and the piece 21C is set to 60 degrees so that the assembling and disassembling can be performed easily and efficiently.

The diameter between the getter 20 and the spacer 21 and between the spacer 21 and the tire 5 is 2 to 7 mm.
A gap S of about a degree is provided, and the gap S allows the furnace core tube 2
The heat transferred to the tire 5 from the getter 20 and the spacer 21 can be reduced. Further, both axial end surfaces of the tire 5 and the flange portion 2 of the spacer 21
A gap S1 of about 0.5 to 1.0 mm is provided between the respective Nos. 3 and 3, and the heat transmitted to the tire 5 can be reduced also by this gap S1.

According to the above embodiment, the spacer 2
By providing 1, the distance between the furnace core tube 2 and the rollers 7A, 7B in the high temperature region (intermediate part) becomes longer by at least the radial dimension (thickness) of the spacer 21, and the furnace core tube 2 becomes longer. Radiant heat exerted on the rollers 7A and 7B is reduced, and the heat insulating effect can be enhanced. Also, each getter 2
0, the spacer 21, and the tire 5 are independent parts, and therefore, in manufacturing the same, a material having heat resistance, mechanical strength, and abrasion resistance can be selected.

Moreover, since the inner diameter of the tire 5 provided at the intermediate portion 2C is larger than the outer diameters of the tires 3 and 4 at both end portions 2A and 2B, the spacer 21 is connected when the tire 5 is replaced. The tire 5 can be easily removed by removing the bolt 24 and disassembling it.
Can be pulled out from the furnace core tube 2 after getting over the tires 3 or 4 at the ends. Even when a new tire 5 to be replaced is attached, the new tire 5 is externally fitted from the end of the furnace core tube 2, and the tire 3 or 4 at the end is passed over to be positioned on the getter 20. Two
By inserting 1A to 21C between the tire 5 and each getter 20 and connecting them with the connecting bolt 24 and the nut 25, they can be easily replaced.

Therefore, the tires 3 or 4 at the end of the furnace core tube 2 can be replaced efficiently without removing them. As described above, according to the first embodiment of the present invention, by supporting the furnace core tube 2 at three points, the hot bending of the furnace core tube 2 between the fulcrums (tires 3 to 5) is allowed within the allowable range. The inside of the rotary kiln can be a large indirect heating type rotary kiln having a large diameter and long shaft core tube, which has never existed before.
Moreover, as described above, not only the heat insulating measures but also the replacement of the intermediate tires is facilitated, and a large rotary kiln can be implemented.

When the spacer 21 is divided into three pieces 21A, 21B, and 21C of large, medium, and small sizes in the circumferential direction as described above, when disassembling, the spacer 21 is sequentially removed from the small piece 21C, and the large piece 21A is assembled.
By assembling in order from above, it can be disassembled smoothly and easily.
Assembly work can be performed. FIG. 6 shows an essential part of the second embodiment of the present invention. Unlike the first embodiment, the spacer 21 is divided into three parts in the axial direction so that the flange part 23 is independent. Therefore, the same operational effects as those of the first embodiment are achieved. Further, on the facing contact surfaces of the respective divided pieces 21A to 21C and the respective flange portions 23,
The spacers 2 are provided with radial steps 26 and 27, respectively.
1 can be assembled accurately and easily.

It should be noted that the spacer 21 may be an integral member without being divided like 21A to 21C. Figure 7
Shows an essential part of the third embodiment of the present invention. The difference from the second embodiment is that the spacer 21 is divided into two pieces.
1A to 21C are provided with flange portions 23, 23 protruding toward the inner diameter side and the outer diameter side, the getter 20 is positioned between the inner diameter side facing surfaces of the flange portion 23, and the shift prevention guide is omitted. Since the flange portion 23 is provided with a guide function for preventing slippage, the assembling / disassembling work is slightly easier than in the first and second embodiments. In addition, welding work for the shift prevention guide is unnecessary.

In the third embodiment, the spacer 21
An annular groove 28 for fitting and positioning the spacer divided pieces 21A to 21C is provided on the facing surfaces of the flange portions 23, 23 that constitute the. The spacer 21 is 21
It may be an integral body without being divided like A to 21C.

FIG. 8 shows a modification of the third embodiment, which is different from that shown in FIG. 7 only in that the annular groove on the surface of the spacer 21 facing the flange portion 23 is omitted.
FIG. 9 shows an essential part of the fourth embodiment of the present invention, and is different from the second embodiment in that a detachable second spacer 29 is interposed between the spacer 21 and the tire 5. That is, the second spacer 29 is the first spacer 21.
Similarly to the above, the divided pieces 29A to 29 are divided into three in the circumferential direction.
Each C is axially divided into three parts so that the tire positioning flange portion 30 is independent, and the divided pieces 29A to 29C are axially connected by a connecting bolt 31 and a nut 32.

The two axial flange portions 30 of the second spacer 29 project to the outer peripheral side, but the inner peripheral side does not interfere with the flange portion 23 of the first spacer 21 and the outer peripheral surface of the flange portion 23. The inner diameter is made large so that a gap S is formed between them. The first and second spacers 21 and 29 are provided with the gaps S and S1 not only between them but also with respect to the getter 20 and the tire 5.

According to the fourth embodiment, although a slightly longer time is required for the assembling / disassembling work, the distance between the tire 5 and the outer peripheral surface of the furnace core tube 2 is further widened, and the furnace core tube 2 and the roller 7A in the high temperature region are expanded. , 7B is sufficiently secured, the tire 5
By increasing the outer diameter of the furnace, the radiant heat from the furnace core tube 2 can be further reduced. In addition, the spacer 21 may be an integral member without being divided like 21A to 21C.

FIG. 10 shows an essential part of the fifth embodiment of the present invention. The difference from the first embodiment is that the spacer 21
The flange portion 23 of each of the divided pieces 21A to 21C is also projectingly provided on the inner peripheral side so that each getter 20 can be fitted between the flange portions 23, and the intermediate portion 2C of the furnace core tube 2 is formed.
It is the point that it is externally fitted to the reinforcing sleeve 33 welded to the sleeve 33, and the shift prevention guide 22 is welded to the sleeve 33, which enhances the strength of the intermediate portion 2C of the furnace core tube 2 and improves the strength Can secure a sufficient distance. In the fifth embodiment, the getter 20 is an integral member in the circumferential direction, and a gap S is provided between the getter 20 and the sleeve 33.

The present invention is not limited to the above embodiment, and for example, in the first to fourth embodiments, the reinforcing sleeve can be welded around the intermediate portion 2C of the furnace core tube 2, and It is possible to configure a large rotary kiln having a large diameter and long axis by supporting the furnace core tube 2 at three or more points.

[0027]

According to the present invention, as described above, the tire is fitted on the middle portion of the furnace core tube through the getter and the detachable spacer, and the tire is rotatably supported by the roller. Therefore, the furnace core tube can be supported at three or more points, and the distance between each fulcrum is set within the allowable range of the hot bending of the furnace core tube. A large indirect rotary kiln can be manufactured and the processing capacity can be increased.

Further, by forming the spacer into a divided structure, it is easy to assemble and disassemble. Since the inner diameter of the tire in the middle part is made larger than the outer diameter of the tires at both ends of the furnace core tube, after disassembling and removing the spacer, remove the tire in the middle part over the tire at one end and remove it. Therefore, it is not necessary to remove the tire at the end portion, and the tire replacement work can be performed easily and efficiently.

[Brief description of drawings]

FIG. 1 is an overall front view showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is an enlarged view of a main part of FIG. 2 (a cross section taken along the line BB of FIG. 4).

4 is a cross-sectional view taken along the line CC of FIG.

5 is an enlarged view of part D in FIG. 4. FIG.

FIG. 6 is a cross-sectional view showing the main part of the second embodiment of the present invention (see FIG. 4).
FIG. 6 is a cross-sectional view corresponding to part D).

FIG. 7 is a cross-sectional view showing the main part of the third embodiment of the present invention (see FIG.
FIG. 6 is a cross-sectional view corresponding to part D).

FIG. 8 is a sectional view showing a modified example of the third embodiment.

FIG. 9 is a cross-sectional view showing a main part of a fourth embodiment of the present invention (see FIG.
FIG. 6 is a cross-sectional view corresponding to part D).

FIG. 10 is a sectional view (corresponding to section D in FIG. 4) showing a main part of a fifth embodiment of the present invention.

FIG. 11 is a front view showing a conventional example.

FIG. 12 is a left side view of FIG. 11.

13 is an enlarged cross-sectional view taken along the line EE of FIG.

14 is a sectional view taken along line FF in FIG.

FIG. 15 is a cross-sectional view (cross-section corresponding to the line EE in FIG. 11) showing another conventional example.

16 is a sectional view taken along line GG of FIG.

FIG. 17 is a cross section showing still another conventional example (G- in FIG.
It is a sectional view corresponding to line G).

[Explanation of symbols]

1 rotary kiln 2 furnace core tube 2A, 2B both ends 2C Intermediate part 3 tires 4 tires 5 Tires in the middle part 7A, 7B roller 11,12 Combustion chamber casing 20 Geta 21 Spacer 21A, 21B, 21C Divided pieces 23 Flange 29 Second spacer 29A, 29B, 29C Divided pieces 30 Flange

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Toshiyuki Hanatani 1-1-1, Nakanomiya Oike, Hirakata City, Osaka Prefecture Kubota Hirakata Manufacturing Co., Ltd. (56) Reference JP-A-10-300356 (JP, A) Flat 9-217988 (JP, A) Actual development Sho 58-83098 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F27B 7/20 F27B 5/10

Claims (4)

(57) [Claims] 1. At least both ends of a metal core tube are rotatably supported by rollers via metal tires fitted onto the core tube, and a combustion chamber is formed on the outer periphery of the core tube between the tires. An indirect heating type rotary kiln, wherein a tire is externally fitted to an intermediate portion of the furnace core tube via a getter and a detachable spacer, and the tire is rotatably supported by rollers. Rotary kiln. 2. The rotary kiln according to claim 1, wherein the spacer is divided in a circumferential direction. 3. The rotary kiln according to claim 1, wherein the spacer is divided in the axial direction. 4. The rotary kiln according to claim 1, wherein an inner diameter of the tire in the middle portion is larger than an outer diameter of the tire in both end portions of the furnace core tube.