JP2914767B2 - Roller hearth type transfer roll for heating furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer roller for a roller hearth type heating furnace having excellent compression resistance and impact resistance.

[0002]

2. Description of the Related Art Rolls of various materials are used as hearth rolls for transporting a strip in a continuous heating furnace for a metal such as a silicon steel sheet, a stainless steel sheet, a galvanized steel sheet or a sheet glass. Various types of heat-resistant alloy rolls, rolls formed by inserting a ceramic sleeve into an iron core, rolls formed by laminating and pressing asbestos boards, and the like are used in accordance with the type of heat-receiving material and processing conditions.

Heretofore, since in this type of hearth rolls used in continuous heating of the strip steel plate or sheet glass flaws to the heated material is extremely disliked were generally punched asbestos plate in a donut shape disk shape Asbestos rolls have been used in which a number of sheet materials are laminated, an iron core is inserted, and compression molded .

[0004] Asbestos rolls utilize the excellent heat resistance, durability and resilience of asbestos fibers, and have an appropriate cushioning property and abrasion resistance to a material to be heated. Many are used as hearth rolls even at a high temperature of 1000 ° C. or more.
It does not withstand use in high temperature areas where the temperature exceeds ℃, and
Due to the problem of asbestos pollution in recent years, asbestos rolls using asbestos fiber as a main raw material require sufficient care for production and use, and high-performance heat-resistant rolls made of asbestos substitutes have been developed.

As an asbestos substitute, a sheet material mainly composed of sepiolite and mica as described in JP-A-1-46571 and JP-A-1-46572, and a sepiolite and an inorganic binder are mainly used. And those relating to sheet materials for rolls such as sheet materials, and between heat-resistant sheet materials as described in JP-A-1-201417, JP-A-2-107716 and JP-A-2-145718. Various proposals have been made regarding a roll structure in which a reinforcing member is immersed.

[0006]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 1-4657 / 1994.
No. 1 and a sheet material of a material as described in JP-A-1-46572 were punched into a donut-shaped disc.
Hearth rolls made of asbestos substitutes obtained by laminating a donut-shaped disc-shaped heat-resistant sheet material , inserting an iron core, and compression molding have good abrasion resistance and do not cause cracks No flaws on the material to be heated, and suitable as a transport roll for various continuous heat treatment furnaces,
Moreover, the above-mentioned JP-A-1-201417 and JP-A-2-10-17
By using a reinforcing structure in which a reinforcing member is immersed between heat-resistant sheet materials as described in JP-A-7716 and JP-A-2-145718, asbestos rolls can also be used in terms of compression resistance and impact resistance. It has performance comparable to.

[0007] However, the above roll has no problem at a high temperature of 1000 ° C or higher, but under a relatively low temperature condition of 1000 ° C or lower, the strip steel sheet is not flexible and has a wavy state. So that they do not evenly contact the roll. As a result, especially at both ends of the strip steel plate, a large impact is repeatedly received, and remarkable wear occurs.

As a method of reducing abrasion, a method of increasing the compression molding pressure during roll production to increase the density, or impregnating the produced roll with an inorganic colloid solution as disclosed in JP-A-63-111118 is used. There is. However, in the former case, to cause breakage Excessively high compression pressure, compression
There is a limit to. In the latter case, the roll after production,
That is, an inorganic colloid solution is applied to a compression-molded sheet material.
It is difficult to uniformly impregnate, since the impregnation of the inorganic colloidal solution is biased in the surface portion amount of the roll, when the surface portion is worn, there is a disadvantage that thereafter rapidly wear will progress.

[0009]

Therefore SUMMARY OF THE INVENTION The present invention is asbestos
Insert a number of donut-shaped disc- shaped heat-resistant sheet material consisting of alternative fibers into the iron core, in the roller hearth-type heating furnace transport roll formed by compression molding , between the heat-resistant sheet material ,
Heat resistant sheet material impregnated with saturated inorganic colloid solution
And 3 to 20% of inorganic colloid solution in terms of solid content
A roller hearth-type heating furnace transport roll, which is compression-molded so as to be uniformly contained throughout .

The present invention also provides a doughnut-shaped disc-shaped heat-resistant sheet made by punching a heat-resistant sheet material made of asbestos substitute fiber.
The doughnut-shaped disc-shaped heat-resistant sheet material is impregnated with the inorganic colloid solution until it is saturated.
The heat-resistant sheet material impregnated with the inorganic colloid solution is inserted into an iron core every one to three donut-shaped disc-shaped heat-resistant sheet materials not impregnated.
The present invention relates to a method for manufacturing a transport roll for a roller hearth type heating furnace, which is characterized by compression-molding a heat sheet material .

[0011]

The transport roll for the roller hearth type heating furnace of the present invention is capable of saturating an inorganic colloid solution between heat-resistant sheet materials.
3 to 2 in terms of solid content
0% inorganic colloid solution is uniformly contained throughout
Because it is compression molded, after roll production (after compression)
Compared to impregnating, the non-impregnated part during compression
Lloyd solution soak, the entire roll evenly inorganic colloidal solution containing Munode not only manufacturing is easy, its
The mechanical strength of the roll is improved, and the wear resistance life of the roll is greatly improved.

Hereinafter, the transport roller for a roller hearth type heating furnace of the present invention will be described in detail with reference to the accompanying drawings. The material of the heat-resistant sheet material used in the present invention is not particularly limited,
Any asbestos substitute that can be used as a roll sheet material may be used. In particular, suitable heat-resistant sheet materials are those described in the above-mentioned JP-A-1-46571 and JP-A-1-46572. The heat-resistant sheet material may be punched into a donut-shaped disk having a predetermined size by a conventional method. The thickness of the heat-resistant sheet material is usually about 2 to 10 mm.

As shown in FIG. 1, doughnut-shaped disc-shaped heat-resistant sheet materials (3) and (4) are iron core (roll shaft) (1)
At this time, a fixing flange (2) is installed at a predetermined position from one end of the iron core. Fixing flange (2)
A heat-resistant sheet material (3) not impregnated with the inorganic colloid solution is inserted into the iron core on which is fixed, and then a heat-resistant sheet material impregnated with the inorganic colloid solution to a saturated state is inserted. Then, a predetermined number of heat-resistant sheet materials are inserted. At this time, Japanese Patent Application Laid-Open Nos.
Needless to say, compression resistance and impact resistance can be improved by inserting reinforcing members (5) as in JP-A-107716 and JP-A-2-145718 at regular intervals.

When the laminate thus obtained is compression molded, the inorganic colloid solution is impregnated from the heat-resistant sheet material impregnated with the inorganic colloid solution into the adjacent heat-resistant sheet material not impregnated with the inorganic colloid solution. The entire roll will uniformly contain the inorganic colloid solution. Further, when the inorganic colloid solution is dried or heated in actual use, the inorganic colloid solution becomes a dry gel, and serves as a strong binder for a heat-resistant sheet material. As a result, the mechanical strength is improved and the wear resistance is remarkably improved. Moreover, since the inorganic colloid solution is evenly contained in the inside of the roll, even if the abrasion progresses, the abrasion progresses rapidly because the roll surface is always firmly bound by the dry gel of the inorganic colloid solution. There is no.

The insertion interval of the heat-resistant sheet material impregnated with the inorganic colloid solution is preferably every one to three sheets. Within this range, by changing the insertion interval according to the pressure during compression molding, the inorganic colloid solution can be inserted. Can be uniformly contained in the inorganic colloid liquid without exuding outside the roll.

If all the sheet material impregnated with the inorganic colloid solution is used, an excessive amount of the inorganic colloid solution flows out during compression molding, which is not preferable. Further, if the insertion interval is four or more, the inorganic colloid solution cannot be uniformly contained inside the roll even if the compression molding pressure is equal to or greater than the breaking load of the heat-resistant sheet material.

Examples of the inorganic colloid solution include silica sol, alumina sol, zirconia sol and the like, and these can be used alone or as a mixture of two or more.

The content of the inorganic colloid solution is preferably 3% or more in terms of solid content based on the weight of the roll, that is, the total weight of the heat-resistant sheet material, and if it is less than this, sufficient abrasion resistance cannot be obtained.

The solid content of the inorganic colloid solution can be adjusted arbitrarily by adjusting the concentration of the inorganic colloid solution, the insertion interval of the heat-resistant sheet material impregnated with the inorganic colloid solution, and the compression molding pressure. . However, the solid content of the inorganic colloid solution has an upper limit. That is,
The upper limit of the concentration of the inorganic colloid solution that can be impregnated into the heat-resistant sheet material is 40% as a result of various investigations. Therefore, in order to contain a large amount of the inorganic colloid solution, the press pressure must be greatly reduced. Because the density hardly increases,
Instead, it has the opposite effect. From the above viewpoint, the upper limit of the solid content is 20%.

It is not preferable to dry the heat-resistant sheet material impregnated with the inorganic colloid solution before producing the roll. Only by drying, the inorganic colloid solution firmly binds and hardens the heat-resistant sheet material, so it is necessary to greatly increase the pressing pressure to obtain the same density as in the case of ordinary non-impregnated. This is because some flexibility is lost and compression failure occurs. On the other hand, when compression molding is performed in an undried state, since the sheet material is softened, there is an advantage that rolls having the same density can be obtained at a lower pressure.

Next, as a method for impregnating the heat-resistant sheet material with the inorganic colloid solution, a conventional method can be used. That is, the heat-resistant sheet material may be immersed in the inorganic colloid solution, and the immersion time can be reduced by pressing the heat-resistant sheet material in a closed container.

The product obtained as described above is provided for use through subsequent drying and surface polishing steps, and any of the above steps may be performed first. When the polishing step is performed first, the drying may be performed prior to use or may be performed during use.

[0023]

EXAMPLES The transport rollers for a roller hearth type heating furnace according to the present invention will be further described below with reference to examples. Example 1 Sepiolite [trade name Milcon SS: manufactured by Showa Mining Co., Ltd.]
A bulk slurry having a bulk specific gravity of 0.8 and a thickness of 5 was prepared by using a slurry composed of 60 parts by weight, 10 parts by weight of mica powder, 10 parts by weight of ceramic fiber, 18 parts by weight of silica powder and 2 parts by weight of pulp.
mm sheet is formed into a round net, dried, and has an outer diameter of 115 mm.
Punched into a donut-shaped disc with an inner diameter of 49 mm, 13
Three (4520 g) heat-resistant sheet materials were produced.

Next, of the 133 doughnut-shaped heat-resistant sheet materials, 66 sheets (2243 g) were added to a silica sol solution (Snowtex 40 manufactured by Nissan Chemical; 40% by weight of SiO ₂ solid content, liquid specific gravity: 1.3). It was immersed for a period of time for impregnation.
Sixty-six (2243 g) sheet materials include silica sol solution 23
33 g (933.4 g as solids) were impregnated (therefore, the silica sol solids content of the whole roll was 1%).
7.1%).

Next, one heat-resistant sheet material not impregnated with the silica sol solution was inserted into an iron core (roll shaft) having a diameter of 48 mm and a length of 550 mm, and then impregnated with the silica sol solution. Insert one heat-resistant sheet material,
By repeating this operation, one heat-resistant sheet material which has not been impregnated at the end is inserted, a total number (133) of heat-resistant sheet materials are inserted, compression molding is performed at a pressure of 90 kg / cm ² , and surface polishing is performed. To produce a roll of the present invention having a length of 400 mm and a diameter of 110 mm.

The obtained roll is heated at 800 ° C. for 8 hours in an electric furnace.
Heating was performed for hours. The heating test was conducted by flowing 5 liters of water per minute through the iron core, placing a stainless steel load roll on the test roll so as to have a linear load of 15 kg / cm ² , and rotating the test roll at 40 rpm. The wear amount and hardness of the roll were measured. Hardness is measured using a rubber hardness meter ASTM
D type was used. Table 1 shows the results.

Example 2 147 heat-resistant sheet materials (49 sheets) produced in the same manner as in Example 1
98g), 49 sheets (1666g) were immersed in a silica sol solution for 5 hours in the same manner as in Example 1. 49 sheets (1666
g) sheet material was impregnated with 1732 g (693 g as solids) of the silica sol solution (therefore, the silica sol solids content of the entire roll was 12.2%).

Next, a heat-resistant sheet material not impregnated with silica sol was used for the same iron core (roll shaft) as in Example 1.
After inserting the sheet, one heat-resistant sheet material impregnated with silica sol and one heat-resistant sheet material not impregnated with silica sol 2
After repeatedly inserting the heat-resistant sheet material not impregnated with silica sol, 150 kg / c
Compressed with a pressure of m ² , polished the surface, length 40
A roll of the present invention having a diameter of 0 mm and a diameter of 110 mm was produced.

The obtained roll was treated with 800 in the same manner as in Example 1.
After heating at ℃ for 8 hours, the hardness and the amount of wear were measured. Table 1 shows the results.

Example 3 In Example 2, the silica sol solution was doubled with water (weight ratio).
A roll was prepared in the same manner as in Example 2 except that a roller diluted with a roller was used, and the hardness and the wear amount after heating were measured. In this case, the content of the silica sol solid content in the entire roll was 5.8%. Table 1 shows the results.

COMPARATIVE EXAMPLE 1 123 heat-resistant sheet materials produced in the same manner as in Example 1 were inserted into an iron core without impregnation with an inorganic colloid solution, and 150 kg
/ Cm ² , and a roll was prepared in the same manner as in Example 1. After heating by the same method as in Example 1, the hardness and the wear amount were measured. Table 1 shows the results.

COMPARATIVE EXAMPLE 2 140 heat-resistant sheet materials and a pressing pressure of 250 kg / c
A roll was prepared and heated in the same manner as in Comparative Example 1 except that the roll was changed to m ^2, and the hardness and the wear amount were measured. Table 1 shows the results.

Comparative Example 3 A roll was prepared in the same manner as in Example 2 except that the silica sol solution diluted 5 times (weight ratio) with water was used, and the hardness and abrasion amount after heating were measured. did. In this case, the content of the silica sol solid content was 2.2%. Table 1 shows the results.

[0034]

Table 1 Example Comparative Example 1 2 3 1 2 3 Number of sheets (sheets) 133 147 147 123 140 147 Pressing pressure (kg / cm ² ) 90 150 150 150 250 150 Silica sol solid content ratio (%) 17.1 12.2 5.8 2.2 Hardness after heating test 93 93 80 35 42 50 Abrasion (mm) 0.8 0.8 1.2 5.0 4.2 3.5

[0035]

The transport roll for the roller hearth type heating furnace according to the present invention maintains the characteristics of the conventional roll made of an asbestos substitute, and easily impregnates the inorganic colloid solution into the unimpregnated portion during compression. In addition, since the entire roll uniformly contains the inorganic colloid solution, not only is the preparation easy, but also the mechanical strength is improved, and the life of the abrasion resistance of the roll is greatly improved.

[Brief description of the drawings]

FIG. 1 is a schematic view showing one embodiment of a transport roll for a roller hearth type heating furnace of the present invention.

[Explanation of symbols]

 Reference Signs List 1 iron core (roll shaft) 2 fixing flange 3 heat-resistant sheet material 4 heat-resistant sheet material 5 reinforcing member

Claims (2)

(57) [Claims] 1. A roller hearth-type heating furnace transport roll obtained by inserting a number of donut-shaped disc- shaped heat-resistant sheet materials made of asbestos substitute fibers into an iron core and compression-molding the heat-resistant sheet materials , Impregnate inorganic colloid solution to saturation
The heat-resistant sheet material thus prepared is disposed, and 3 to 20 in terms of solid content.
% Inorganic colloid solution so that it is uniformly contained throughout
A transfer roller for a roller hearth type heating furnace, which is formed by compression molding . 2. A heat resistant sheet material made of asbestos substitute fiber is punched.
Cut out to form a donut-shaped disc-shaped heat-resistant sheet material
To the doughnut-shaped disc-shaped heat-resistant sheet material.
The impregnated heat-resistant sheet material impregnated with the inorganic colloid solution is inserted into the iron core every one to three donut-shaped disc-shaped heat-resistant sheet materials that have not been impregnated. A method for producing a roller-hearth type heating furnace transport roll, comprising compression-molding a large number of heat-resistant sheet materials inserted into a heating roller.