JPS59127957A - Roll for conveying high temperature material - Google Patents

Abstract

PURPOSE:To convey a high temp. material with the peripheral surfaces of annular heat insulating members and to suppress the heat loss of the material by connecting and fitting alternately the plural heat insulating members and stationary members having the diameter smaller than the diameter of said insulating members via stress relieving members on the cylindrical part of a roll shaft. CONSTITUTION:A sintered molding composed of powder of ceramics as a raw material is used as an annular heat insulating material 2 that contacts directly with a high temp. material in terms of a heat insulating effect, strength and wear resistance. The member 2 is fitted via a stress releasing member 3 onto a roll shaft 1 and therefore the roll diameter is increased but the distance D between roll shafts can be decreased by disposing the adjacent rolls in proximity to each other in such a way that the projecting and recessed surfaces cross with each other without interference by making the width size (a) of a stationary member 4 larger than the width size (b) of the member 2. Even if the roll diameter is large, the increase in the distance between the shaft and the instability of the material conveyed atop the rolls, and the trouble such as impact on the roll are averted.

Description

Detailed Description of the Invention The present invention relates to a conveyor roll for conveying high-temperature materials such as continuously cast slabs to the next process, and in particular, a heat insulating member is provided on the roll surface to prevent heat loss of the material by the roll during the conveyance process. This is to suppress the

Hot charging, in which continuously cast slabs are transported in a high-temperature state using conveyor rolls and charged into a heating furnace without being cooled, makes effective use of the heat capacity of the slabs! ll
Since this is an attempt to improve the 11 method, it is desired that the transported slab undergoes little temperature drop during transport and is charged into a furnace at as high a temperature as possible.

However, since the transport roll is made of an iron alloy, the slab supported by the roll loses a large amount of heat through the contact surface with the roll during transport. Heat loss due to this roll is one of the main factors limiting the energy saving effect in hot charging.

As a way to reduce this heat loss, it is effective to install a heat insulating layer on the roll body that supports the slab to avoid direct contact between the slab and the metal surface. Covered saws tend to peel off and break down early due to the load on the slab and stress caused by the difference in coefficient of thermal expansion between the roll metal and the heat insulating material layer. Furthermore, since the roll diameter increases by the thickness of the heat insulating material layer on the surface, the distance between the axes of adjacent rolls X1(d)'e must be increased accordingly. As a result, the horizontal position of the slab carried on roll "2" becomes unstable, and while the roll (r)l is moving, the slab (S)
Not only does the vertical movement of the leading and trailing ends of the slab cause a shock to the roll, but the high temperature of the slab also causes the leading end to curve (sag). The frequency of damage to the roll due to collisions with other objects increases, and in the end, the roll cannot be used in practical use as a transport roll.

The present invention solves the above-mentioned problems and provides a heat insulating effect and the robustness required as a conveyor roll.

The conveyance roll of the present invention has a plurality of annular heat insulating members that are encircled around the body of a metal roll shaft via stress relaxation members, and fixed members having a smaller diameter than the heat insulating members, which are alternately connected in the axial direction of the shaft. It is composed of a group of rolls arranged in a ring, and conveys a high-temperature material such as a slab supported on the circumferential surface of an annular heat insulating member.

FIG. 1 is an axial sectional view showing an embodiment of the present invention, and FIGS. 2 and 3 are an AA sectional view and a BB sectional view, respectively. (1) is a metal roll shaft made of iron alloy, (2)
) is an annular heat insulating member mounted around the body of the roll shaft (1). In order to accommodate the difference in thermal expansion coefficient between each annular heat insulating member (2) and the roll shaft (1), an appropriate gap is formed between the inner peripheral surface thereof and the outer peripheral surface of the roll shaft. (3) is a stress relaxation member, which is installed in the gap between the annular heat insulating member (2) and the roll shaft (1), and is used to reduce the radial gap and force caused by the difference in thermal expansion coefficient between the two. Absorbs and softens impact against weak ceramics.

(4) is a fixing member, which has the role of preventing displacement of each annular heat insulating member (2) in the axial direction.

As shown in the figure, a plurality of annular heat insulating members (2) are alternately connected to fixing members (4) along the axial direction of the roll shaft (1) via stress relaxation members (3) to form a shaft body. A roll (R) is constructed by enclosing the parts.

The rolls (R) are supported at the end of the shaft via bearings @++ in the same way as normal rolls, and although not shown, are arranged horizontally in parallel, and each axis is rotated by a rotational drive mechanism. It rotates smoothly. A high-temperature material (S) such as a slab, which is a material to be conveyed, is supported on the circumferential surface of the annular heat insulating member (2) and conveyed on the roll.

The constituent material of the annular heat insulating member (2), which is in direct contact with the high-temperature material, is selected from various heat insulating materials, but ceramics (e.g. alumina, Manufactured by known pressureless sintering methods, pressure sintering methods, etc., using powders of silicon carbide, silicon nitride, zirconia, etc., and those related to material combinations or structural combinations thereof) as raw materials. Sintered compacts are preferably used.

The stress relaxation member (3) is made of a material with a low elastic modulus that easily creates a gap between the annular heat insulating member (2) and the shaft (1) and the deformation required to absorb and alleviate an impact force. Further, as a structure that performs such a function, for example, a spring (3) as shown in FIG. 5 may be used. Of course, in either case, it is necessary to be able to withstand thermal effects from high-temperature materials.

The fixing members (4) are located on both sides of each annular heat insulating member (2), are themselves fixed to the shaft (1), and are in contact with each annular heat insulating member (1) from both sides thereof. This prevents the annular heat insulating member (2) from slipping in the axial direction, especially when the stress relaxation member (3) is highly deformable. Therefore, the fixing member (2) is usually made of metal and is fixed to the shaft (1) as a narrow ring or a relatively wide hollow cylinder. Note that the fixing member (4) needs to have a smaller diameter than the annular heat insulating member so as not to come into contact with the high temperature material supported on the circumferential surface of the annular heat insulating member (2). The circumferential surface of the roll formed by alternately forming the fixing members (2) and the fixing members (4) has an uneven surface as shown in the figure.

In the roll of the present invention, the annular heat insulating member (2) is arranged as a plurality of divided members on the shaft alternately with the fixed member, so that stress in the axial direction due to thermal expansion of the annular heat insulating member (2) is less generated. Radial deformation due to differences in thermal expansion of the shaft is absorbed by the stress relief member (3). In addition, the amount of thermal expansion of the annular heat insulating member (2) in the axial direction is the same as that of the shaft (1).
If the size is larger than that of the fixing member (4
), but if the annular heat insulating member is made of ceramic, it can withstand it sufficiently (the compressive strength of ceramic is about 10 times the tensile strength); When the amount of expansion is larger, the load on the heat insulating member is extremely light because it is not directly subjected to tensile force from the fixed member.

In addition, since the roll of the present invention has an annular heat insulating member mounted around the roll shaft, the roll diameter is increased accordingly, but as shown in the above @1 diagram, the width dimension (a) ta of the fixing member (4)
If the width dimension (b) of the J-shaped section heating member is made larger than that shown in Fig. 4, adjacent rolls can be arranged close to each other so that their uneven surfaces intersect without interfering with each other, as shown in Fig. 4. By doing so, the distance (D) between the roller axes can be narrowed. Therefore,
Even if the roll diameter is large, as shown in FIG. Trouble can be avoided.

Examples of the roll of the present invention include: (1) Roll shaft: Material: chromium molybdenum steel, carbon steel, etc., body outer diameter 2
00 mm, length 2000 mm, (11) Annular heat insulating member: ceramic sintered body, inner diameter 230 m, outer diameter 4.
OOmm, width (length) 200 mm, (iii) Stress relaxation member: combination of spring steel rings, inner diameter 200 mm
, outer diameter 230 mm, width (length) 190 mm, (
Fixed member: Hollow cylinder made of carbon steel, alloy steel, etc., inner diameter 2
It is constructed as shown in Fig. 1 with each member having an outer diameter of 270 m, a width (length) of 205 mm, and adjacent rolls are arranged so that the unevenness of the circumferential surface intersects with the shaft as shown in Fig. 4. The thermal insulation effect during the transportation of high-temperature materials by the φX-configured conveyor rolls arranged with a distance of about 350 mm is not uniform depending on the insulation material of the original heat insulating member, but it is compared to the case of conventional ordinary conveyor rolls. However, the amount of heat loss is reduced by about 50%.

As described above, the conveyance roll of the present invention has an excellent heat-insulating effect on high-temperature materials and enhances the energy-saving effect in charging. In addition, the heat insulating material on the circumferential surface of the roll effectively avoids stress caused by temperature changes and impact caused by conveyed materials, so it does not easily break or peel, and is sufficiently durable for long-term use. .

[Brief explanation of drawings]

Fig. 1 is an axial sectional view showing an embodiment of the present invention, Fig. 2 is an AA sectional view, Fig. 3 is a BB sectional view, and Fig. 4 is a main part illustrating the mutual arrangement of the rolls. A plan view, FIG. 5 is a cross-sectional view of main parts showing another example of the present invention, and FIG.
It is a side explanatory view which shows an example. roll shaft, 2: annular heat insulating member, 3: stress relaxation member, 4: fixed member, S: high temperature material. Agent Patent Attorney Shinhachibe Miyazaki

Claims (3)

[Claims] (1) A plurality of annular heat insulating members, which are encircled via stress relaxation members, and fixing members having a smaller diameter than the annular heat insulating members are alternately connected and encircled around the body of the metal roll shaft. A high-temperature material transport roll consisting of a group of rolls. (2) The high temperature material conveying roll according to item (1) above, wherein the annular heat insulating member is a sintered molded body made of ceramic. (3) Adjacent rolls are arranged such that the irregularities of the peripheral surfaces formed by the respective annular heat insulating members and fixing members intersect with each other. High temperature material conveyor roll.