JPH09203483A - Elbow - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce local abrasion caused by collision of a powder and granular material so as to exhibit abrasion resistance performance of a ceramic elbow sufficiently by providing with a rotary mechanism on both ends, and connecting the both ends to a fixing transferring pipe through a flange joint. SOLUTION: An elbow is fixed to a fixing transferring pipe 12 through a flange joint 5, and also the main body of a reduction gear 4 is fixed to the fixing transferring pipe 12. A ceramic flexible hose 1 is mounted in the flange joint 5, and the reduction gear 4 and an elbow driving device 2 are set therein, power transferred from the elbow driving device 2 to a drive shaft 3 is transferred to the reduction gear 4 mounted in the flange joint 5 of a passive side, and both ends of the flexible hose 1 are rotated in the same direction through gears 10, 11 at two points of a driving side and the passive side. Abrasion caused by collision of a powder and granular material which flows in the elbow is shared with the whole of an elbow inner surface ceramics by the rotation so as to reduce generation of remarkable abrasion caused by fixed type local concentration collision.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elbow for a transport pipe for pneumatically transporting powdered particles such as coal ash, pulverized coal, limestone, etc. in a coal fired boiler.

[0002]

2. Description of the Related Art A conventional ash transport pipe elbow has an inner surface made of a ceramic pipe and a ceramic style, or a wear resistant castable, and an outer surface protected by using a steel pipe, a 25Cr cast iron pipe, or the like. , They were replaced when the metal loss due to wear became remarkable.

[0003]

FIG. 6 is a cross-sectional view showing a main ash collision area in a conventional ash transport pipe elbow, which includes a primary collision area, a secondary collision area, and a tertiary collision area. Significant wear occurs on the part. The primary colliding part from the straight pipe on the inlet side of the elbow is the most worn, and then the secondary colliding part and the tertiary colliding part are locally worn.

In the ceramic lining or the like, it is possible to physically extend the life of the ceramics by thickening the primary to tertiary collision parts, but it is unclear which part is the collision part. In addition, due to the difficulty in manufacturing, it is generally manufactured with a uniform thickness.

The present invention is intended to reduce the local wear due to the above-mentioned primary to tertiary collisions in the elbow and to sufficiently exhibit the wear resistance of the ceramic elbow.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above problems and relates to an elbow having the following features. (1) In an elbow used for a transportation pipe for conveying powdery particles by air, a ceramics flexible hose through which the powdery particles pass, a flange joint for slidably supporting both ends of the hose, and the same hose. Large-diameter gears mounted around both ends of the small-diameter gear, small-diameter gears meshing with the large-diameter gears, respectively, rotary drive device connected to the rotary shaft of one of the small-diameter gears, each small-diameter gear Around the ceramic flexible hose via a drive shaft connecting the rotary shaft of the ceramic flexible hose through a universal joint, a guide attached to the outer periphery of the central portion of the ceramic flexible hose, and a roller that rolls according to the movement of the guide. It consists of a steady rest that is fixed to the enclosure fixing part, and the Elbow having both ends connected to the fixed transport tube. (2) The elbow according to the above item (1), wherein the guide is an oval link guide eccentrically provided with respect to the ceramic flexible hose.

[0007]

1 is a perspective view of an ash transport pipe elbow according to a first embodiment of the present invention, FIG. 2 is a vertical sectional view of the elbow, FIG. 3 is a sectional view taken along line III-III of FIG. FIG. 4 is an enlarged view of the IV portion of FIG. In the figure, 1 is a ceramic flexible hose. This is a well-known product which has been manufactured and marketed in the past. Reference numeral 2 is an elbow drive device, that is, a servomotor. Reference numeral 3 is a drive shaft, and 4 is a speed reducer whose rotating shaft is connected to the elbow drive device. The end of the drive shaft 3 and the rotating shaft of the speed reducer 4 are connected by a universal joint. Reference numeral 5 is a flange joint, 6 is a Teflon packing, 7 is a steady rest with a roller, 8 is a roller, and 9 is a guide along which the roller rolls along its groove. This guide is attached to the outer circumference of the ceramic flexible hose. Reference numeral 10 is a small-diameter gear attached to the rotary shaft of the speed reducer 4, and 11 is a large-diameter gear attached around the end of the ceramic flexible hose 1. These gears mesh with each other to form the speed reducer 4. There is. 12 is a fixed transportation pipe. This elbow is fixed to the fixed transportation pipe 12 via flange joints 5 at both ends. The main body of the speed reducer 4 is also fixed to the fixed transportation pipe 12.

In this apparatus, the ceramic flexible hose 1 is first mounted on the flange joint 5. The speed reducer 4 and the elbow drive device 2 are set on this. Further, the power transmitted from the elbow drive device 2 to the drive shaft 3 is transmitted to the speed reducer 4 mounted on the passive side flange joint 5, and the two ends of the flexible hose 1 are connected to the gears 10 and 11 at the drive side and the passive side. Rotate in the same direction via. By this rotation, the wear caused by the collision of the powder particles flowing in the elbow is shared by the entire elbow inner surface ceramics, and the occurrence of significant wear due to the fixed local concentrated collision is reduced.

Further, in order to prevent vibration of the flexible hose, a steady rest 7 with a roller is provided. The steady rest 7 itself is fixed, and the guide 9 attached to the flexible hose 1 contacts the roller 8 of the steady rest 7 in its ring-shaped portion and rotates while rotating it. The Teflon packing 6 is provided between the end of the flexible hose 1 and the flange joint 5,
The flexible hose 1 is slidable with respect to the flange joint 5. This prevents the fluid flowing inside from leaking when the flexible hose 1 is rotating. The elbow according to the present embodiment can effectively utilize the entire inner surface of the elbow as compared with the fixed elbow, so that the thickness reduction due to wear of the elbow is 1/4 or less. Further, not only the 90 ° elbow but also an elbow with an irregular angle can be applied.

FIG. 5 is a cross-sectional view of an ash transport pipe elbow according to a second embodiment of the present invention. In the figure, 9A is an oval link guide, which is used in place of the guide 9 in the first embodiment. The oval link guide 9A is thicker on one side in the radial direction than on the other side, and its center is not concentric with the center of the elbow but is located at a different position. 7A is a steady rest, and the ring portion is provided concentrically with the elbow, but the lengths of the legs of the roller 8A are not the same. The configuration other than the above is the same as that of the first embodiment.

In this apparatus, the elbow can be slightly meandered and rotated. As a result, the primary collision portion can be moved further, and wear can be further reduced.

[0012]

In the elbow of the present invention, since it is rotated by the large diameter gear attached to both ends of the elbow and the small diameter gear connected to the driving device, the local collision of the transport powder particles is dispersed over the entire inner surface of the elbow. Local wear can be prevented and life can be extended. Further, in the case where the oval link guide is provided as the guide, the collision can be further dispersed and the life can be extended.

[Brief description of drawings]

FIG. 1 is a perspective view of an ash transport pipe elbow according to a first embodiment of the present invention.

FIG. 2 is a vertical sectional view of the elbow.

FIG. 3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is an enlarged view of a part IV in FIG. 2;

FIG. 5 is a cross-sectional view of an ash transport pipe elbow according to a second embodiment of the present invention.

FIG. 6 is a cross-sectional view showing main ash collision sites in a conventional ash transport pipe elbow.

[Explanation of symbols]

 1 Ceramics Flexible Hose 2 Elbow Drive Device 3 Drive Shaft 4 Reduction Gear 5 Flange Joint 6 Teflon Packing 7,7A Steady Rest 8,8A Roller 9 Guide 9A Oval Link Guide 10 Gear 11 Gear 12 Fixed Transport Pipe

Claims (2)

[Claims] 1. An elbow used for a transportation pipe for conveying powder particles by air, a ceramic flexible hose through which the powder particles pass, a flange joint for supporting both ends of the hose so as to be slidably rotatable, respectively. Large-diameter gears mounted around both ends of the hose, small-diameter gears meshing with the large-diameter gears, and rotary drive devices connected to the rotary shafts of either one of the small-diameter gears, respectively. The drive shaft connecting the rotary shaft of the small diameter gear via a universal joint, the guide attached to the outer periphery of the central portion of the ceramic flexible hose, and the roller that rolls in response to the movement of the guide, It consists of a steady rest that surrounds the periphery and is fixed to the fixed part, And an elbow whose both ends are connected to a fixed transportation pipe. 2. The elbow according to claim 1, wherein the guide is an oval link guide eccentrically provided with respect to the ceramic flexible hose.