Composite heat-resistant cushion block for steel rolling heating furnace, steel rolling heating furnace and application of composite heat-resistant cushion block

Abstract

The invention discloses a composite heat-resistant cushion block for a steel rolling heating furnace, the steel rolling heating furnace and application of the composite heat-resistant cushion block and relates to the technical field of steel production. The cushion block is designed to be of a multi-material composite structure, the cushion block body provides good supporting force, the abrasion-resistant ceramic coating on the surface of the cushion block body can reduce abrasion of the cushion block body, the service life of the composite heat-resistant cushion block is prolonged, and the maintenance cost of the composite heat-resistant cushion block is reduced. Due to the fact that the heat insulation opening is formed in the cushion block body, the material cost of the cushion block body is reduced, the heat insulation material is filled in the heat insulation opening, the overall weight of the composite heat-resisting cushion block is reduced, and meanwhile the heat insulation material and the heat insulation layer in the heat insulation opening can effectively prevent heat from diffusing. Therefore, the low temperature of the water beam is prevented from spreading to the surface of the wear-resistant ceramic coating, and the quality defects of black marks on the surface of the steel billet, uneven heating temperature and the like are relieved.

Description

Technical Field

[0001] The present invention relates to the technical field of steel production, and in particular to a composite heat-resistant pad for a steel rolling heating furnace, the steel rolling heating furnace and applications thereof. Background Art

[0002] In the steel rolling industry, the steel rolling heating furnace is a key link in the production process. It is responsible for heating the steel billet to a temperature suitable for rolling. However, during the heating process, the steel billet is in direct contact with the pads in the steel rolling heating furnace, which will cause black marks on the surface of the steel billet, uneven heating temperature, short service life of the pads, and high maintenance costs. When the steel billet has quality problems such as black marks and uneven heating temperature, it not only affects the dimensional tolerance control of the rolled product, but also causes quality defects of the rolled product.

[0003] In view of this, the present invention is proposed. Summary of the invention

[0004] The object of the present invention is to provide a composite heat-resistant pad for a steel rolling heating furnace, a steel rolling heating furnace and applications thereof.

[0005] The present invention is achieved in that:

[0006] In the first aspect, the present invention provides a composite heat-resistant pad for a steel rolling heating furnace, comprising a pad body, one of the surfaces of the pad body is provided with a wear-resistant ceramic coating, a surface of the pad body away from the wear-resistant ceramic coating is provided with a heat-insulating opening, the heat-insulating opening extends in a direction close to the wear-resistant ceramic coating, and the heat-insulating opening is filled with heat-insulating material, and a pad insulation layer is also provided on the end face of the heat-insulating opening, and the pad insulation layer is configured to contact the water beam of the steel rolling heating furnace.

[0007] In an optional embodiment, the thermal conductivity of the wear-resistant ceramic coating is smaller than that of the pad body.

[0008] Preferably, the thermal conductivity of the wear-resistant ceramic coating is 1 / 5 to 1 / 4 of the thermal conductivity of the pad body.

[0009] Preferably, the thickness of the wear-resistant ceramic coating is 4.5-5.5 mm, more preferably 5 mm.

[0010] Preferably, the material of the wear-resistant ceramic coating includes aluminum oxide and rare metal oxides.

[0011] In an alternative embodiment, the thermal conductivity of the insulating material is lower than that of the spacer body.

[0012] Preferably, the thermal conductivity of the thermal insulation material is 1.5 / 1000 to 2.0 / 1000 of the thermal conductivity of the pad body.

[0013] Preferably, the thermal insulation material comprises aluminum silicate ceramic fibers or nano thermal insulation materials.

[0014] Preferably, the volume of the heat-insulating opening is 25-35% of the volume of the cushion block body.

[0015] In an optional embodiment, the heat-insulating layer of the pad block is composed of a heat-insulating material, and the thickness of the heat-insulating layer of the pad block is 10 to 20 mm.

[0016] In an optional embodiment, the material of the pad body is a cobalt-based alloy, preferably a Co50 alloy.

[0017] Preferably, the height of the cushion block body is 100-110 mm.

[0018] Preferably, the length of the cushion block is 150-200 mm.

[0019] In a second aspect, the present invention provides a steel rolling heating furnace, comprising a furnace body, a water beam, a clamp block and a composite heat-resistant pad block as described in any of the aforementioned embodiments; the water beam, the clamp block and the composite heat-resistant pad block are all arranged in the furnace body, the composite heat-resistant pad block is fixed to the water beam by the clamp block, and the pad insulation layer of the composite heat-resistant pad block is in contact with the water beam.

[0020] In an optional embodiment, a plurality of composite heat-resistant pads are provided on the water beam for conveying the steel billets, and the plurality of composite heat-resistant pads are staggered along both sides of the center line of the water beam.

[0021] In an optional embodiment, a water beam fire-resistant wrapping layer is provided in an area on the surface of the water beam where the composite heat-resistant pad is not installed.

[0022] In an optional embodiment, the water beam fire-resistant wrapping layer includes a water beam insulation layer and a fire-resistant wrapping layer, the water beam insulation layer is in contact with the water beam, and the fire-resistant wrapping layer is located on the outer surface of the water beam insulation layer.

[0023] Preferably, the thickness of the water beam insulation layer is 15 to 25 mm, and the thickness of the fire-resistant wrapping layer is 45 to 55 mm.

[0024] In a third aspect, the present invention provides a use of a steel rolling heating furnace as described in any of the aforementioned embodiments for reducing black marks on the surface of steel billets during steel production.

[0025] The present invention has the following beneficial effects:

[0026] The present invention provides a composite heat-resistant pad for a steel rolling heating furnace, a steel rolling heating furnace and applications thereof, wherein the pad is designed to be a structure composite of multiple materials, wherein the pad body provides good supporting force, and the wear-resistant ceramic coating on its surface can reduce the wear of the pad body, thereby increasing the service life of the composite heat-resistant pad and reducing the maintenance cost of the composite heat-resistant pad. Since a heat-insulating opening is provided inside the pad body, the material cost of the pad body is reduced, and the heat-insulating opening is filled with heat-insulating material, thereby reducing the overall weight of the composite heat-resistant pad. At the same time, the heat-insulating material and the heat-insulating layer in the heat-insulating opening can effectively prevent heat diffusion, thereby slowing down the low temperature of the water beam from spreading to the surface of the wear-resistant ceramic coating, thereby alleviating quality defects such as black marks on the surface of the steel billet and uneven heating temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 A side view of a composite heat-resistant pad provided in an embodiment of the present invention;

[0029] Figure 2 A schematic diagram of the structure of a water beam and a composite heat-resistant pad provided in an embodiment of the present invention;

[0030] Figure 3 for Figure 2 Sectional view of section AA;

[0031] Figure 4 for Figure 3 A magnified view of some structures;

[0032] Figure 5 This is a top view of the composite heat-resistant pads inside the steel rolling heating furnace after installation.

[0033] Explanation of the main component symbols: 10-rolling heating furnace; 100-composite heat-resistant pad; 110-pad body; 111-insulation opening; 120-wear-resistant ceramic coating; 130-insulation material; 140-pad insulation layer; 200-water beam; 210-center line of the water beam; 300-block. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0035] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0037] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0038] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0039] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] First embodiment

[0041] Please refer to Figure 1 The present embodiment provides a composite heat-resistant pad 100 for a steel rolling heating furnace, including a pad body 110, one surface of which is provided with a wear-resistant ceramic coating 120, and the wear-resistant ceramic coating 120 is configured to contact the lower surface of the steel billet, thereby playing a supporting role when the steel billet is heated in the steel rolling heating furnace 10.

[0042] Please refer to Figure 2 and Figure 3 The steel billet passes through the heating furnace along the center line 210 of the water beam. The existing pads are arranged along the center line 210 of the water beam. After long-term research, the inventors found that the key reason for the quality problems such as black marks and uneven heating of the steel billet is that the steel billet is in direct contact with the pads during the heating process. The pads are installed on the water beam 200 of the steel rolling heating furnace 10, and the cooling medium flows inside the water beam 200. Therefore, the temperature of the pads is greatly affected by the temperature of the cooling medium in the water beam 200, which causes quality problems such as black marks and uneven heating of the steel billet after direct contact with the pads.

[0043] In order to solve the above problems, the thermal conductivity of the wear-resistant ceramic coating 120 provided in this embodiment is smaller than that of the pad body 110, so that the heat transfer effect between the pad body 110 and the wear-resistant ceramic coating 120 is deteriorated. The steel billet is directly in contact with the wear-resistant ceramic coating 120 with a smaller thermal conductivity, and the temperature drop on the lower surface of the steel billet is significantly reduced, thereby alleviating the phenomenon of black marks appearing on the surface of the steel billet.

[0044] In this embodiment, in order to ensure a good difference in thermal conductivity, the material of the pad body 110 is Co50 cobalt-based alloy, and the thermal conductivity is approximately 82W / (m·K); the material of the wear-resistant ceramic coating 120 is aluminum oxide (Al2O3) and rare metal oxides, which gives the product excellent hardness and wear resistance. The thermal conductivity of the wear-resistant ceramic coating 120 is approximately 20W / (m·K), and the thermal conductivity of the wear-resistant ceramic coating 120 is 24% of the thermal conductivity of the pad body 110.

[0045] The high temperature environment in the steel rolling heating furnace 10 requires that the material of the pad has good high temperature resistance. Among them, Co50 cobalt-based alloy has excellent high temperature resistance, corrosion resistance and creep resistance, can remain stable in a high temperature environment, and is an ideal material for the pad in the steel rolling heating furnace 10. The material of the wear-resistant ceramic coating 120 has high hardness, high wear resistance, high temperature resistance of 1300°C, and good bonding performance with the pad body 110.

[0046] In this embodiment, in order to ensure the wear resistance and thermal conductivity of the wear-resistant ceramic coating 120, the thickness of the wear-resistant ceramic coating 120 is 5 mm.

[0047] The wear-resistant ceramic coating 120 can be prepared by uniformly coating the material of the wear-resistant ceramic coating 120 on the top of the pad body, and then using heat treatment or other process means to ensure that the wear-resistant ceramic coating 120 is firmly bonded to the pad body 110 .

[0048] During the heating process, the steel billet will rub against the pad, causing wear on the pad surface. Traditional pads are not sufficiently wear-resistant, which can easily affect the service life of the pad and the surface quality of the steel billet. The embodiment of the present invention significantly improves the wear resistance of the composite heat-resistant pad 100 by providing a wear-resistant ceramic coating 120 on the surface of the pad body 110, and can effectively resist the direct wear of the steel billet on the composite heat-resistant pad 100 at high temperatures, reduce the wear amount and replacement frequency of the composite heat-resistant pad 100, thereby reducing production costs and ensuring the surface quality of the steel billet.

[0049] Please refer to Figure 4 Furthermore, in order to reduce the temperature of the cooling medium in the water beam 200 from being transferred to the wear-resistant ceramic coating 120 and reduce the phenomenon of black marks on the surface of the steel billet, a heat-insulating opening 111 is provided on the surface of the pad body 110 away from the wear-resistant ceramic coating 120. The heat-insulating opening 111 extends in a direction close to the wear-resistant ceramic coating 120 but does not contact the wear-resistant ceramic coating 120. The heat-insulating opening 111 is filled with heat-insulating material 130. A pad insulation layer 140 is also provided on the end face of the heat-insulating opening 111. The pad insulation layer 140 is configured to contact the water beam 200 of the steel rolling heating furnace 10.

[0050] By opening a heat-insulating opening 111 on the surface of the pad body 110 away from the wear-resistant ceramic coating 120, and filling the inside of the heat-insulating opening 111 with a heat-insulating material 130, and cooperating with the pad heat-insulating layer 140, not only can the heat transfer effect between the water beam 200 and the pad body 110 be reduced, and the temperature drop of the pad body 110 be avoided, but also, the mass of the heat-insulating material 130 is smaller than the mass of the pad body 110, and the weight of the pad body 110 can be significantly reduced. In addition, the existing heat-resistant pads are relatively expensive because they are made of alloy materials as a whole. The embodiment of the present invention can not only reduce the production cost of the composite heat-resistant pad 100 by filling the inside of the pad body 110 with the heat-insulating material 130, but also ensure the structural strength of the composite heat-resistant pad 100, and ensure the stability and reliability of the composite heat-resistant pad 100 under harsh working conditions.

[0051] Furthermore, in order to ensure a good heat insulation effect and alleviate the appearance of black marks on the surface of the steel billet, the thermal conductivity of the heat insulation material 130 is smaller than that of the pad body 110 .

[0052] In this embodiment, the heat insulating material 130 is a common aluminum silicate ceramic fiber blanket, and the thermal conductivity of the heat insulating material 130 is about 0.15 W / m·K, which is 1.8‰ of the thermal conductivity of the cushion block body 110 .

[0053] In order to ensure the thermal insulation effect of the thermal insulation material 130 , ordinary aluminum silicate ceramic fiber blanket can be compressed and then filled into the thermal insulation opening 111 . For example, a 20-40 mm thick aluminum silicate ceramic fiber blanket is compressed to 10-20 mm thick and then filled into the thermal insulation opening 111 .

[0054] In this embodiment, in order to ensure a good heat insulation effect, the volume of the heat insulation opening 111 is 30% of the volume of the cushion block body 110 .

[0055] In this embodiment, the pad insulation layer 140 is a high-aluminum ceramic fiber blanket. The thickness of the pad insulation layer 140 after pressing is 10 mm. The thermal conductivity of the pad insulation layer 140 is approximately 0.10 W / m·K, which is 1.3‰ of the thermal conductivity of the pad body 110.

[0056] In this embodiment, the height of the cushion block body 110 is 110 mm, and the length of the cushion block is 150 mm.

[0057] This embodiment provides a composite heat-resistant pad 100 for a steel rolling heating furnace, and the processing process thereof is as follows:

[0058] The Co50 cobalt-based alloy is precision cast into the shape and size of the pad block body 110, and a wear-resistant ceramic coating 120 is plated on the surface of the pad block body 110 away from the thermal insulation opening 111 through heat treatment. The thermal insulation opening 111 of the pad block body 110 is filled with a pressed ordinary aluminum silicate ceramic fiber blanket, and then a pressed high-aluminum ceramic fiber blanket with good volume stability and toughness is used as a pad insulation layer 140 and is laid and fixed on the end face of the thermal insulation opening 111 of the pad block body 110.

[0059] Second embodiment

[0060] Please refer to Figure 4 and Figure 5 The present embodiment provides a steel rolling heating furnace 10, including a furnace body (not shown), a water beam 200, a block 300 and the composite heat-resistant pad 100 provided in the first embodiment.

[0061] The water beam 200 , the block 300 and the composite heat-resistant pad 100 are all arranged in the furnace body. The composite heat-resistant pad 100 is fixed on the water beam 200 through the block 300 , and the pad insulation layer 140 of the composite heat-resistant pad 100 is in contact with the water beam 200 .

[0062] In order to avoid black marks on the surface of the steel billet, a plurality of composite heat-resistant pads 100 are arranged on the water beam 200 for conveying the steel billet. The plurality of composite heat-resistant pads 100 are staggered along both sides of the center line 210 of the water beam.

[0063] For example, in this embodiment, the composite heat-resistant pads 100 are alternately arranged in pairs on the left and right sides of the center line 210 of the water beam to ensure that different positions of the steel billet contact the composite heat-resistant pads 100 during the movement of the steel billet in the steel rolling heating furnace 10, further reducing the possibility of black marks.

[0064] In other embodiments, the composite heat-resistant pads 100 may be arranged alternately in single arrangement, three arrangement, four arrangement, etc., on the left and right sides along the center line 210 of the water beam.

[0065] In this embodiment, in order to ensure the normal use of the water beam 200, a fire-resistant wrapping layer of the water beam 200 is provided in the area on the surface of the water beam 200 where the composite heat-resistant pad 100 is not installed.

[0066] In this embodiment, the fire-resistant wrapping layer of the water beam 200 includes a water beam 200 insulation layer and a fire-resistant wrapping layer. The water beam 200 insulation layer is in contact with the water beam 200, and the fire-resistant wrapping layer is located on the outer surface of the water beam 200 insulation layer.

[0067] In this embodiment, the heat insulation layer of the water beam 200 is also an aluminum silicate ceramic fiber blanket with a thickness of 20 mm; the refractory wrapping layer is cast on-site using mullite explosion-proof quick-drying self-flowing castable with a thickness of 50 mm.

[0068] The present embodiment provides a steel rolling heating furnace 10, and its installation process and working principle are as follows:

[0069] The processed composite heat-resistant pad 100 is installed on the surface of the water beam 200, and the pad insulation layer 140 is in direct contact with the water beam 200. The pad insulation layer 140 uses 20mm thick high-aluminum ceramic fiber compressed into 10mm thickness. The compression-formed pad insulation layer 140 has excellent volume stability and toughness. Then the composite heat-resistant pad 100 is fixed on the water beam 200 by the clamping block 300, and the water beam 200 insulation layer is covered on the surface of the water beam 200, and then the refractory wrapping layer is poured.

[0070] Multiple composite heat-resistant pads 100 are installed alternately in pairs along the left and right sides of the center line 210 of the water beam. After all the composite heat-resistant pads 100 are installed, the consistency of the top surface elevations of the multiple composite heat-resistant pads 100 is checked, and the top surface elevation difference of different composite heat-resistant pads 100 is required to be controlled within ±1mm to ensure that the installation accuracy of the composite heat-resistant pads 100 meets the process design requirements of the steel rolling heating furnace 10.

[0071] The first comparison

[0072] This comparative example provides a pad for a steel rolling heating furnace, which has a structure similar to that of the first embodiment, except that the pad body 110 is entirely composed of Co50 cobalt-based alloy, does not contain a wear-resistant ceramic coating 120, and does not have a heat insulation opening 111.

[0073] This comparative example also provides a steel rolling heating furnace 10, which has a structure similar to that of the second embodiment, except that the pad block and the water beam 200 provided in this comparative example are directly fixed through a clamping block 300.

[0074] The same conditions were used to detect the temperature of the upper surface of the pads in the steel rolling heating furnace 10 of the second embodiment and the first comparative example. The temperature of the upper surface of the composite heat-resistant pad 100 of the second embodiment was 76°C higher than that of the pad of the first comparative example.

[0075] The same conditions are used to detect the steel temperature at the black mark of the steel billet after the steel billet passes through the steel rolling heating furnace 10 of the second embodiment and the first comparative example. The steel temperature at the black mark of the steel billet passing through the steel rolling heating furnace 10 of the second embodiment is 21°C higher than that of the first comparative example, and the black mark is significantly lighter, which effectively improves the quality of the steel billet.

[0076] In summary, the composite heat-resistant pad 100 for a steel rolling heating furnace, the steel rolling heating furnace 10 and the application thereof provided by the present invention have at least the following advantages:

[0077] By arranging a wear-resistant ceramic coating 120 on the top of the pad body 110 and adding a heat insulation layer between the bottom of the pad body 110 and the water beam 200, the wear resistance of the pad is significantly improved and the service life of the composite heat-resistant pad 100 is extended.

[0078] The wear-resistant ceramic coating 120 has a smaller thermal conductivity than the material of the pad body 110 and a pad insulation layer 140 is added to the bottom, which is beneficial to reducing the heat transfer between the high-temperature steel billet and the cooling water beam 200, and can significantly increase the temperature of the top surface of the pad body 110, which is beneficial to reducing the black mark of the water pipe on the surface of the steel billet and improving the uniformity of the heating temperature of the steel billet.

[0079] The pad body 110 is made of Co50 alloy, which has excellent high temperature resistance, corrosion resistance and creep resistance, and can maintain stable performance in a high temperature environment.

[0080] The composite heat-resistant pad 100 needs to withstand the heavy load of the steel billet and the high temperature environment in the steel rolling heating furnace 10, so it must have sufficient structural strength. The bottom of the composite heat-resistant pad 100 in the present invention adopts a hollow structure design and is filled with insulation material 130, which not only reduces the weight but also ensures the overall strength, ensuring the stability and reliability of the composite heat-resistant pad 100 under harsh working conditions.

[0081] Traditional high-performance heat-resistant alloy pads are expensive, increasing equipment and production costs. The present invention achieves the goal of reducing costs while ensuring performance by adopting a composite structure design and combining the advantages of high-performance materials and low-cost materials.

[0082] By alternately arranging the composite heat-resistant pads 100 on both sides of the center line of the water beam 200, the contact position of the composite heat-resistant pads 100 on the water beam 200 changes during the stepping process of the steel billet in the steel rolling heating furnace 10, which is also beneficial to reduce the black marks of water pipes on the surface of the steel billet and improve the uniformity of the heating temperature of the steel billet.

[0083] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A composite heat-resistant pad for a steel rolling heating furnace, characterized in that: It includes a pad block body, one of the surfaces of which is provided with a wear-resistant ceramic coating, a surface of the pad block body away from the wear-resistant ceramic coating is provided with a heat-insulating opening, the heat-insulating opening extends in a direction close to the wear-resistant ceramic coating, and the heat-insulating opening is filled with heat-insulating material, and the end face of the heat-insulating opening is also provided with a pad block heat-insulating layer, and the pad block heat-insulating layer is configured to contact with the water beam of the steel rolling heating furnace.

2. The composite heat-resistant pad according to claim 1, characterized in that: The thermal conductivity of the wear-resistant ceramic coating is smaller than that of the pad body; Preferably, the thermal conductivity of the wear-resistant ceramic coating is 1 / 5 to 1 / 4 of the thermal conductivity of the pad body; Preferably, the thickness of the wear-resistant ceramic coating is 4.5 to 5.5 mm, more preferably 5 mm; Preferably, the material of the wear-resistant ceramic coating includes aluminum oxide and rare metal oxides.

3. The composite heat-resistant pad according to claim 1, characterized in that: The thermal conductivity of the thermal insulation material is smaller than that of the pad body; Preferably, the thermal conductivity of the thermal insulation material is 1.5 / 1000 to 2.0 / 1000 of the thermal conductivity of the cushion block body; Preferably, the thermal insulation material comprises aluminum silicate ceramic fiber or nano thermal insulation material; Preferably, the volume of the heat insulation opening is 25-35% of the volume of the cushion block body.

4. The composite heat-resistant pad according to claim 3, characterized in that: The pad block heat insulation layer is composed of the heat insulation material, and the thickness of the pad block heat insulation layer is 10 to 20 mm.

5. The composite heat-resistant pad according to claim 1, characterized in that: The material of the pad body is a cobalt-based alloy, preferably a Co50 alloy; Preferably, the height of the cushion block body is 100-110 mm; Preferably, the length of the cushion block is 150-200 mm.

6. A steel rolling heating furnace, characterized in that: It comprises a furnace body, a water beam, a clamping block and the composite heat-resistant pad as described in any one of claims 1 to 5; the water beam, the clamping block and the composite heat-resistant pad are all arranged in the furnace body, the composite heat-resistant pad is fixed to the water beam by the clamping block, and the pad insulation layer of the composite heat-resistant pad is in contact with the water beam.

7. The steel rolling heating furnace according to claim 6, characterized in that: A plurality of the composite heat-resistant pads are arranged on the water beam for conveying steel billets, and the plurality of the composite heat-resistant pads are staggeredly arranged along both sides of the center line of the water beam.

8. The steel rolling heating furnace according to claim 6, characterized in that: A water beam fire-resistant wrapping layer is provided on the surface of the water beam in an area where the composite heat-resistant pad is not installed.

9. The steel rolling heating furnace according to claim 8, characterized in that: The water beam fireproof wrapping layer comprises a water beam insulation layer and a fireproof wrapping layer, the water beam insulation layer is in contact with the water beam, and the fireproof wrapping layer is located on the outer surface of the water beam insulation layer; Preferably, the thickness of the water beam insulation layer is 15 to 25 mm, and the thickness of the fire-resistant wrapping layer is 45 to 55 mm.

10. Use of the steel rolling heating furnace as claimed in any one of claims 6 to 9 in reducing black marks on the surface of steel billets during steel production.

Images