JP2651834B2 - High heat resistance roll - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a highly heat-resistant roll for transporting a metal, glass or ceramics in a heat treatment furnace.

(Prior art and its problems) In a heating furnace that continuously heat-treats, a large number of rolls move in the traveling direction for loading and unloading steel slabs, steel plates, stainless steel plates, steel pipes, glass sheets, ceramic sintered bodies, and the like. They are arranged at right angles to them. In particular, rolls juxtaposed in a furnace are required to have heat resistance, wear resistance, smoothness, and non-adhesion to an object to be heat-treated.

Conventionally, this type of roll has been attempted to apply a ceramic or cermet coating to the peripheral surface of the heat-resistant alloy roll main body by a thermal spraying method or the like. There is a problem with adhesion,
In actual use, due to the difference in the coefficient of thermal expansion between the roll body and the coating layer, there is a drawback that the roll body is easily peeled off when subjected to thermal stress, thermal shock, or mechanical shock.

On the other hand, according to Japanese Patent Publication No. 59-22613, a thermal spraying intermediate layer composed of a mixture of mullite and a bonding metal and a spray coating uppermost layer of mullite are formed on the surface of the roll base material via a bonding metal layer. Thus, a heat-resistant roll comprising at least two layers and having excellent build-up resistance and peel resistance has been proposed and disclosed.

However, it is difficult to apply the mullite concentration stepwise and uniformly with a heat-resistant roll such as the Japanese Patent Publication No. 59-22613, it is easy to peel off hot, and it is effective in continuous operation in a temperature range of 500 ° C or less. However, the intermittent operation at a temperature of 500 ° C. or more has a drawback that it is easily separated due to thermal stress, thermal shock or mechanical shock.

Alternatively, a metal shaft and a sintered body made of an inorganic material are used. Rolls in which a sleeve made of ceramics is engaged have been tried, and a gap is previously formed at room temperature in consideration of the difference in thermal expansion coefficient between the metallic shaft and the sleeve made of ceramics. It is one ideal form that these gaps become zero at the operating temperature. However, there is a defect that the ceramic sleeve is easily destroyed in actual use because there are deformations such as an adjustment error and non-uniformity of a use temperature, a variation in dimensional accuracy of a metal shaft and a sleeve, and a warp. .

On the other hand, according to Japanese Patent Publication No. 59-150011, a ceramic fiber, rock wool, refractory as a shock absorbing material is provided in a gap between a roll body portion made of ceramic which is a sintered body of an inorganic material and a roll shaft. An excellent heat-resistant roll that absorbs a difference in thermal expansion between the roll shaft and the ceramic roll main body or the like by filling the roll is provided and disclosed.

Further, according to Japanese Patent Publication No. 53-110611, an outer cylinder made of ceramic which is a sintered body made of an inorganic material, an inner cylinder made of an inorganic or organic refractory and heat-insulating material, and a heat-resistant material made of a metal iron core are used. Roles have been proposed and disclosed. The heat-resistant roll disclosed in JP-B-53-110611 will be described with reference to the drawings. As shown in FIG. 5 and FIG. 6, asbestos which is a fire-resistant heat insulating material is applied to the outer periphery of a metal iron core (a).
An inner cylinder (b) made of fire-resistant and insulating bricks containing ceramic fiber, alumina or silica is fitted therein, and a thin cylindrical ceramic roll (c) is fitted as an outer cylinder outside thereof.

However, in a heat-resistant roll such as that disclosed in Japanese Patent Publication No. 53-110611, when a ceramic fiber solidified product is used for the inner cylinder (b) fitted as a heat insulating layer, the volume shrinkage and creep of the ceramic fiber during heating are increased. Due to the deterioration of the strength, a gap is generated between the metal core (a), the inner cylinder (b) of the ceramic fiber solidified product, and the outer cylinder (c) of the ceramic roll, and each iron core and the inner core are formed. Since the cylinder (b) and the outer cylinder (c) run idle while hot or the inner cylinder (b) of the ceramic fiber solidified product breaks, the inner cylinder (b) and the outer cylinder (c) are actually used. ) Or these two types are easily destroyed.

(Means and Actions for Solving the Problems) The present invention aims to eliminate and solve the above-mentioned drawbacks of the prior art, and as a means for achieving this object, a high heat-resistant roll described in the claims is used. To provide.

That is, the present invention relates to a high heat resistance roll formed by fitting a cylindrical ceramic sintered body to a metal core material as shown in FIG. In order to prevent slipping or destruction with the material, as the thermal expansion absorbing material, the buffer material whose outer diameter part is tapered toward both ends and the inner diameter part is processed into a tapered shape corresponding to the buffer material And a high heat-resistant roll provided with the cylindrical ceramic sintered body.

By processing the ceramic sintered body and the buffer material into a tapered shape, the adhesion between the ceramic sintered body of the outer layer and the buffer material of the inner layer is increased, and it is possible to prevent the cylindrical ceramic sintered body from spinning. became.

Further, by tightening the cushioning material, the adhesion between the cushioning material and the cylindrical ceramic sintered body is further strengthened, and it is possible to prevent the cylindrical ceramic sintered body from spinning.

Hereinafter, the configuration of the high heat resistance roll of the present invention will be described in detail with reference to the drawings.

1 and 2 are a longitudinal sectional view and a partially cutaway front view, respectively, of the high heat-resistant roll of the present invention. As shown in FIG. 1, the outer diameter of the metal core (3) is changed to the outer circumference. A tapered cushioning material is fitted into both ends.

In the present invention, the buffer material (2) is mainly composed of inorganic fibers, and is composed of one or more of an inorganic binder, an inorganic filler and an organic binder.

The reason for using the cushioning material (2) is that the metal core material (3)
Is to absorb thermal expansion in the outer peripheral direction of the substrate.

In FIGS. 1 and 2, the cushioning member is formed by laminating a number of annular members (donuts).

This means that when the inorganic fibers are used, the arrangement direction of the fibers is arranged at right angles between the metal core material (3) and the ceramic sintered body (1) as the outer layer, and the load of the conveyed object is adjusted. It is for supporting more effectively. This is because, when the fiber array is arranged in the horizontal direction, since the compressive strength is low, the thickness is reduced depending on the load of the conveyed object, and a gap is generated.

Further, by arranging the inorganic fibers in the right-angle direction, compression fitting can be performed by the collar portions (4) provided at both ends of the metal core material (3).

In other words, by forming the cushioning material into the above-mentioned annular material and compressively fitting the same, the stress remains in the cushioning material even when the heat-resistant roll is used, thereby absorbing the thermal expansion and contraction in the length direction of the metal core material. You can do it.

Further, the inorganic fibers used for the cushioning material are silica
Alumina fiber, alumina fiber, zirconia fiber, any of whiskers may be used,
In order to absorb the difference in thermal expansion, silica-alumina fibers are more effective, and among them, those in which alumina is 45 to 95% by weight and the balance is silica are more preferable. .

The reason is that fibers containing less than 45% by weight of alumina have low heat resistance and tend to undergo volume shrinkage or strength deterioration at temperatures above 600 ° C. On the other hand, fibers containing more than 95% by weight of alumina generally use a solution method. A crystalline fiber to be spun, the fiber strength is very weak, and the fiber is easily broken when compression-fitted by the collars (4) provided at both ends of the metal core material (3). Sometimes it is difficult to leave stress.

Further, an organic binder may be used to increase the strength at the time of fitting into the buffer material (2) made of the silica-alumina fiber, an inorganic binder may be used to increase hot stress, and By using an inorganic filler exhibiting different sintering strengths in a use temperature range, for example, a knotty viscosity or an alumina powder, it is possible to prevent the compression deformation due to the load of the conveyed material.

Further, the strength of the cushioning material (2) can be arbitrarily adjusted by the composition depending on the use temperature, the load of the conveyed material, the diameter of the heat-resistant roll, and the like, and the outer layer (1) of the roll and the metal core (3) can be adjusted. A stepless multi-layer roll in which the strength is changed stepwise during the period is conceivable, but the circumferential thickness of the annular molded body (2) needs to be at least 10 mm or more. If the thickness in the circumferential direction is 10 mm or less, the strength after fitting is insufficient, and the fitting may be broken by fitting pressure of the collar (4) at the time of fitting, or may be broken by a load of a conveyed article in actual use. There is a risk of doing it.

Further, a cylindrical ceramic sintered body (1) having both ends processed into a tapered shape, such as alumina or silicon carbide, is fitted to the outside of the cushioning material (2). It is desirable that the outer diameter of the cushioning material (2) is made to match the inner diameter of the cylindrical ceramic sintered body (1) by lathing after fitting, but a slight clearance is provided in advance and the heat-resistant inorganic adhesive is used. It is also effective to adhere with.

As described above, the feature of the present invention is that a cylindrical ceramic sintered body (1) is formed between a metallic core material (3) and a cylindrical ceramic sintered body (1) tapered toward both ends. A cushioning material (2) formed into a tapered shape corresponding to the binding is supported by fitting, and a high heat-resistant roll is provided without providing an engaging portion.

(Example) A heat-resistant roll having the structure shown in FIGS. 1 and 2 was manufactured and tested. Metal core material (3) and collar (4) are made of stainless steel and have an outer diameter of 22 mm. Buffer material (2) is made of silica / alumina fiber 60%, Kibushi clay 20%, and alumina fine powder 20% with some organic binder. After forming into a wet-formed sheet, it was pressed to a bulk density of 1.0 (g / cm ³ ) after drying. After that, the cushioning material is 24 mm inside diameter, 35 mm outside diameter, 5 m thick
24mm inside diameter, 35-45m outside diameter for tapered part
m, and punched out into a ring having a thickness of 5 mm, and fitted to the metal core material (3) so that both ends were tapered. Bulk density after fitting 1.
After press-compression to 2 (g / cm ³ ), the collar (4) was temporarily temporarily welded to the metal core (3) and fixed.

Further, the outer diameter of the cushioning material was turned. The processing shape is
Both ends were tapered from the end to 20 mm, and the other parts were cylindrical. The outer diameter of the cylindrical portion was set to 50 mm, and the maximum outer diameter of the tapered end portions was set to 60 mm. Thereafter, the temporary welding of the metal core material (3) on one side and the collar (4) is removed, the tapered buffer material (2) on one side is removed from the metal core material (3), the outer diameter is 70 mm, and both ends are tapered. A cylindrical ceramic sintered body (1) processed so as to correspond to the shape of the cushioning material (2) with a maximum inner diameter of the portion of 60 mm and an inner diameter of the cylindrical portion of 50 mm is fitted using a silica-based adhesive. Then, the cushioning material of the tapered portion on one side which was removed earlier was fitted and compressed again by the same pressure, then the collar (4) was fitted and welded and fixed to the metal core (3), and the high heat-resistant roll Was made.

As shown in FIGS. 3 and 4, a metal core material (3) and a collar (4) were made of stainless steel and had an outer diameter of 22 mm, a silica-alumina fiber wet molded product, and a bulk density of 0.3 (as shown in FIGS. 3 and 4). g / cm ³ ), a sleeve having an inner diameter of 22 mm and an outer diameter of 50 mm was used as an intermediate layer (6), and a cylindrical alumina ceramic sintered body (5) having an inner diameter of 50 mm and an outer diameter of 70 mm was formed using a silica-based adhesive. A fitted heat-resistant roll was manufactured.

The high heat-resistant roll of the present invention shown in FIG. 1 and FIG. 2 and the conventional heat-resistant roll shown in FIG. 3 and FIG.
The test was performed in the hot load drive test furnace shown in FIG. 9 and FIG. FIG. 7 was tested in this test furnace for 7 days.
FIG. 3 is a graph of a heat pattern showing the results. In the high heat-resistant roll shown in FIG. 3, the cylindrical alumina ceramic sintered body as the outer layer started to idle at 1000 ° C. for 2 hours, and turned to the intermediate layer after 1100 ° C. for 10 hours. A silica-alumina fiber wet-molded product (6) falls into a powdery form from the gap between the collar (8) and the cylindrical alumina ceramic sintered body (5), and does not function as a transport roll. .

(Effects of the Invention) As described above, the high heat-resistant roll according to the present invention is constituted by the buffer material mainly composed of inorganic fibers inserted between the metal core material and the cylindrical ceramic sintered body, The body and the cushioning material can be made practically usable by making both ends tapered in a shape corresponding to each other, making it possible to use a lighter weight roll compared to conventional ceramic sintered rolls and heat-resistant cast steel rolls. According to the type of the heat-treated material, it is possible to arbitrarily select a multilayer ceramic roll material and provide a transport roll having no face-to-face attack.

Also, by adjusting the bulk density, thickness, etc. of the cushioning material,
A roll having a high heat insulating property was obtained, and it became possible to use the roll as a transport roll irrespective of an anhydrous cold shaft or a metal shaft.

[Brief description of the drawings]

FIG. 1 is a sectional view of the high heat-resistant roll of the present invention, FIG. 2 is a partially broken section corresponding to FIG. 1, FIG. 3 is a sectional view of a roll of a comparative example, and FIG. FIG. 5 is a longitudinal sectional view of a roll showing a conventional example of Japanese Patent Publication No. 53-11061, FIG. 6 is a partially broken sectional view corresponding to FIG. The figure is a graph showing the heat pattern, FIG. 8 is a longitudinal sectional view of the test furnace, and FIG. 9 is IX in FIG.
It is sectional drawing seen along -IX. Description of reference numerals (1), (5), (c): ceramic sintered body (2): buffer material (3), (7), (a): metal core material (4), ( 8) Metal collar (b) Ceramic fiber hardening inner cylinder (9) Test roll, free to move up and down and rotate freely. (10)… Stainless steel roll and driven by motor (11)… Electric furnace

Claims (1)

(57) [Claims] 1. A high heat resistance roll composed of a metal core, a cylindrical ceramic sintered body, and a buffer material mainly composed of inorganic fibers inserted between the metal core and the cylindrical ceramic sintered body. The inner diameter of the cylindrical ceramic sintered body is tapered toward the end, and the cushioning material is formed by laminating a number of annular materials, and the cylindrical ceramic sintered body is A high heat-resistant roll characterized in that the outer diameter is tapered toward the end so as to correspond to the shape of the inner diameter of the unit.