JPS629517Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a sealing device for a portion of an external heating rotary furnace that penetrates the heating furnace wall.

External heating rotary furnaces have a long cylindrical shape, and are rotated by being supported by two rollers at both ends. The object to be heated is placed inside, surrounded by a heating furnace, and heated by hot air flowing around the outside.

Heating temperature varies depending on the object to be heated, but maximum is 750℃
The steel plates that form the cylindrical surface of rotary furnaces are exposed to harsh conditions during operation.

Therefore, it is unavoidable for rotary furnaces to elongate significantly during operation compared to when cooled, and to cause slight eccentricity, but the seal in the part of the rotary furnace that penetrates the heating furnace wall prevents the above elongation and eccentricity. This makes it extremely difficult.

If the sealing device is incomplete, hot air will blow out, causing heat loss, or room temperature air will be sucked in, lowering the heating temperature and lowering the work yield, resulting in economic loss in either case.

Conventionally, methods as shown in FIG. 1, FIG. 2, and FIG. 3 have been used to solve this problem. Figure 1 shows a type of sealing device that brings the asbestos packing directly into contact with the surface of the rotary furnace.A metal fitting 3 that holds the asbestos packing 2 is attached to a bolt 5 fixed to the heating furnace 4 with a large gap 6. However, the range of use is limited due to the fact that the asbestos packing 2 has a short lifespan due to heat and wear, and if the rotary furnace 1 becomes severely eccentric due to thermal deformation, it will not be able to escape through the gap 6. limited to extremely low temperatures.

FIG. 2 shows a labyrinth type packing 7. This type does not use asbestos, so it is heat resistant, but if the rotary furnace has a large elongation or eccentricity, it is necessary to reduce the bite of the labyrinth or lengthen the gap. It does not create resistance and cannot exhibit a sealing effect.

FIG. 3 shows an asbestos cloth 9 hanging onto the surface of the rotary furnace 1 from a metal fitting 8 fixed to the heating furnace 4 with a lip-type gasket, and the end of the asbestos cloth 9 being attached to the surface of the rotary furnace 1 using a coil spring 10. It is tightened. With this method, gas leaks through the openings of the cloth, and the asbestos cloth wears out due to heat and abrasion and cannot withstand long-term use.

In other words, it can be said that in the past, there was no technology to deal with the large elongation and eccentricity of the rotary furnace. The present invention provides a sealing device that solves this problem.

In this invention, the fan-shaped plates of asbestos plates for brake lining, which have increased heat resistance by mixing copper powder etc. on the surface of the rotary furnace, are arranged in two rows to form a double ring, and are in direct contact with the surface of the rotary furnace. In particular, the inside and outside of the heating furnace are shut off. The base plate that supports the asbestos board is also a fan-shaped ring divided into the same number of asbestos boards, and its center is supported at one point by a retainer bolt fixed to the furnace wall and a coil spring inserted into it. , both ends are connected to the adjacent base plate by springs.
However, the hole into which the center support presser bolt is inserted is an elongated hole in the radial direction, allowing each base plate to shift in the radial direction and swing around the presser bolt.

Also, since one of the two rows of asbestos plates is attached to the base plate out of phase, leakage due to the gaps between the sectors is greatly reduced.

With the above structure, even when the eccentricity of the rotary furnace is large, the two rows of asbestos sector plates can follow the eccentricity and maintain a sealing effect without creating a large gap between the rotary furnace surface and each plate. It is something to give.

Next, an example will be explained with reference to the figures. Reference numeral 1 denotes a rotary furnace, and a circular hole larger than the diameter of the rotary furnace 1 is bored in the part that penetrates the furnace wall of the heating furnace 4 in order to escape the eccentricity. There is a void in the. An edge metal fitting 11 is incorporated around the circular hole of the heating furnace 4 to reinforce the edge of the circular hole.
The base plate 13 is fixed by fixing the presser bolt 12 and a coil spring 12' fitted therein.
is supported so as to be in contact with the heating furnace wall. However, as shown in FIG. 5, there is only one holding bolt 12 for one base plate 13, and the bolt hole 14
is a long hole that allows the base plate 13 to shift in the radial direction and swing around the holding bolt 14.

The base plate 13 is a fan-shaped plate made by dividing a circular ring into many parts, and a length-adjustable coil spring 1 is provided with a certain gap between each adjacent base plate.
They are pulled together by 5. Therefore, the base plate 13 is always pushed toward the center, and a force is exerted that presses the asbestos plate 16 held by the base plate 13 against the surface of the rotary furnace 1. A reinforcing plate 17 is welded to the surface of the rotary furnace 1 to prevent wear caused by the asbestos plate 16.

The asbestos board 16 is a fan-shaped board made by mixing metal powder such as copper and barium etc. into brake lining material and hardening it. Two of the asbestos boards 16 are stacked and fixed between the base plate 13 and the mounting plate 19 using mounting bolts 18. be done. However, a spacer 20 is sandwiched between the two asbestos plates 16. Of the two asbestos plates 16, the one on the base plate 13 side is attached with a slight phase shift to prevent hot air or air from leaking from the gap maintained between one base plate 13 and an adjacent base plate 13. In other words, the phase-shifted length of the asbestos plate 16 enters into the adjacent base plate 13 and is displaced relative to that base plate 13, so the two asbestos plates are placed in order to avoid friction with the asbestos plate of the base plate 13. 16 are attached with a gap maintained by the spacer 20.

With the structure described above, the numerous fan-shaped base plates individually displace while forming a ring as a whole to lightly tighten the rotary furnace surface, and the two rows of asbestos plates connect each other to close the gap. Therefore, the gap between the heating furnace and the rotary furnace can be sealed with very high precision compared to the structure of the prior art.

Although the asbestos plate wears out due to wear, it can be easily replaced with a new one, so it can be used semi-permanently as the sealing device.

This invention seals rotary furnaces with a high degree of precision, which was not possible with conventional technology, and the effect is significant by significantly increasing thermal efficiency, saving energy, and improving product yield. This brings about cost reduction.

[Brief explanation of the drawing]

1, 2, and 3 are rotary furnace sealing devices of the prior art, FIG. 4 is a side sectional view of the sealing device of the present invention, and FIG. 5 is a front view of the base plate. 1: Rotary furnace, 2: Graphite asbestos packing,
4: Heating furnace, 7: Labyrinth sealing device, 9:
Lip type seal device, 10: coil spring,
12: Holder bolt, 13: Base plate, 1
4: Long hole, 15: Connection spring, 16: Asbestos board, 19: Mounting plate, 20: Spacer.

Claims (1)

[Claims for Utility Model Registration] (1) The fan-shaped base plate, which is made by dividing a circular ring into many parts, has a long hole in the radial direction in the center, and is in contact with the wall of the heating furnace with bolts on one side, and with the same shape on the other side. A sealing device for an external heat type rotary furnace, characterized in that an asbestos plate is attached, both ends of which are connected to adjacent base plate ends by coil springs, and the inner end surface of the asbestos plate is pressed against the outer peripheral surface of the rotary furnace. (2) The sealing device for an external heating rotary furnace according to claim 1, wherein the asbestos plates according to claim 1 are provided in two rows, one of which is installed out of phase.