CN112593164B

CN112593164B - High-temperature alloy cushion block of heating furnace

Info

Publication number: CN112593164B
Application number: CN202011402372.9A
Authority: CN
Inventors: 肖利; 任艳丽
Original assignee: Pangang Group Panzhihua Iron and Steel Research Institute Co Ltd
Current assignee: Pangang Group Panzhihua Iron and Steel Research Institute Co Ltd
Priority date: 2020-12-02
Filing date: 2020-12-02
Publication date: 2022-03-22
Anticipated expiration: 2040-12-02
Also published as: CN112593164A

Abstract

The invention relates to a high-temperature alloy cushion block of a heating furnace, belonging to the technical field of ferrous metallurgy. The invention provides a high-temperature alloy cushion block of a heating furnace, which comprises the following chemical components in percentage by mass: 16-55% of Co, 10-35% of Cr, 10-30% of Ni, 2-5% of Al and the balance of Fe; the high-temperature alloy cushion block of the heating furnace is prepared by smelting and pouring in sequence, wherein the adding sequence of alloy elements during smelting is sequentially Ni, Cr and Co, and Al is added 3-5 minutes before molten alloy is discharged and poured. The invention focuses on the existing process and equipment, does not need to greatly modify the process and the equipment, and has the advantages of small implementation difficulty and low implementation cost; the service life of the cushion block can be prolonged to 3-5 years, and the production cost is obviously reduced. In addition, the manufacturing process of the alloy cushion block has universality and has a prospect of popularization and application on various steel rolling heating furnaces.

Description

High-temperature alloy cushion block of heating furnace

Technical Field

The invention relates to a high-temperature alloy cushion block of a heating furnace, belonging to the technical field of ferrous metallurgy.

Background

The high-temperature alloy cushion block of the heating furnace is used as an important part for production and operation of the heating furnace, mainly used for bearing steel billets and protecting water pipes, and reducing the black print temperature difference of the steel billets to a certain extent, and is very important for the design and operation of the whole heating furnace. The design of the high-temperature alloy cushion block is primarily considered to reduce the black mark on the lower surface of the produced billet, improve the stability of the rolling process and stabilize the overall length performance of the final product, but in the practical engineering application, the effect of the high-temperature alloy cushion block is slowly highlighted from reducing the black mark to influencing the quality of the final product. In the production of steel products with high quality requirements, the quality of the cushion blocks also results in the quality of the final products, such as heavy rail production, high surface quality hot rolled sheet and strip production, and the like.

An important indicator affecting the quality of the spacer is the service life of the spacer. The traditional cushion block is cast by adding ferrochrome on the basis of cobalt base. As the temperature of the environment reaches 1300 ℃ after long-term use, the cushion block is seriously burnt, the average monthly burning loss rate reaches 4-7 percent, and the service life is 2-3 years. After the cushion block is burnt, on one hand, the heated steel billet can be damaged, the quality of a final product is influenced, and on the other hand, the production cost is also increased.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention aims to provide a high-temperature alloy cushion block of a heating furnace.

The invention provides a high-temperature alloy cushion block of a heating furnace, which comprises the following chemical components in percentage by mass: 16-55% of Co, 10-35% of Cr, 10-30% of Ni, 2-5% of Al and the balance of Fe; the high-temperature alloy cushion block of the heating furnace is prepared by smelting and pouring in sequence, wherein the adding sequence of alloy elements during smelting is sequentially Ni, Cr and Co, and Al is added 3-5 minutes before molten alloy is discharged and poured.

Through the combined action of the alloy elements, the oxidation resistance of the alloy product is enhanced, the hot corrosion at high temperature is prevented, and the service life of the cushion block is prolonged. On the basis, the service life of the cushion block is further prolonged by optimally controlling the process conditions.

Further, the high-temperature alloy cushion block of the heating furnace comprises the following chemical components in percentage by mass: 18-25% of Co, 14-23% of Cr, 15-24% of Ni, 2-5% of Al and the balance of Fe.

Further, the high-temperature alloy cushion block of the heating furnace comprises the following chemical components in percentage by mass: 48-55% of Co, 25-35% of Cr, 15-25% of Ni, 2-5% of Al and the balance of Fe.

Wherein, Co, Cr, Ni and Al are all in industrial pure state, and the content is 99.99% or more.

Further, the Co content is controlled according to the deviation of plus or minus 5-15% according to different cushion block marks.

Furthermore, the content of Cr and Ni is controlled to be 5-10% lower than that of Co of the same grade.

Further, the smelting end point temperature is more than or equal to 1650 ℃.

Further, the smelting end point temperature is 100-300 ℃ higher than the highest melting point temperature of the added alloy.

The invention provides a high-temperature alloy cushion block of a heating furnace, which can reduce oxidation burning loss and prolong the service life. The invention focuses on the existing process and equipment, does not need to greatly modify the process and the equipment, and has the advantages of small implementation difficulty and low implementation cost; the service life of the cushion block can be prolonged to 3-5 years, and the production cost is obviously reduced. In addition, the manufacturing process of the alloy cushion block has universality and has a prospect of popularization and application on various steel rolling heating furnaces.

Detailed Description

The scheme of the invention will be explained with reference to the examples. It will be appreciated by those skilled in the art that the following examples are illustrative of the invention only and should not be taken as limiting the scope of the invention. The examples, where specific techniques or conditions are not indicated, are to be construed according to the techniques or conditions described in the literature in the art or according to the product specifications. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available.

EXAMPLE 1 production of alloy shim according to the invention

1. The formula of the Co20 alloy cushion block used in the low temperature section (less than or equal to 1000 ℃) of the heating furnace comprises the following components in percentage by mass:

TABLE 1

Chemical composition	Content/%
		Co	18-25
Cr	14-23
		Ni	15-24
Al	2-5
		Fe	Balance of

2. The formula of the Co50 alloy cushion block used in the high temperature section (>1000 ℃) of the heating furnace comprises the following components in percentage by mass:

TABLE 2

Chemical composition	Content/%
		Co	48-55
Cr	25-35
		Ni	15-25
AL	2-5
		Fe	Balance of

The smelting end point temperature is higher than the highest melting point temperature of the added alloy by 100-300 ℃, and the smelting end point temperature is more than or equal to 1650 ℃; under the premise of smelting a bottom material, adding Ni, Cr and Co into the alloy elements in sequence;

the adding time of Al is 3-5 minutes before the molten alloy is discharged and poured.

The following illustrates the beneficial effects of the present invention by comparison: a certain domestic steel mill has three heating furnaces, the maximum heating temperature is 1350 ℃, the average temperature is 1050 ℃, and the annual operation time is 320 days. The cushion blocks in the heating furnace are Co20 and Co50 cushion blocks with corresponding marks, the service life is about 2 years, and the monthly average burning loss rate is 0.58 percent.

It is recommended to replace the spacer produced in accordance with example 1 of the present invention. By implementing the invention, the average monthly oxidation burning loss rate of the cushion block of the enterprise is reduced to 0.23%, the service life of the cushion block is prolonged to 3-5 years, the annual maintenance consumption of the cushion block is reduced by 1.2 tons, the annual treatment cost of the final product quality caused by the cushion block is reduced by 272 ten thousand yuan, and the purchase price of the cushion block is 180 ten thousand yuan/ton. The invention has the following benefits after implementation:

reducing consumption of W-cushion block monovalent plus cushion block to influence quality treatment cost

＝1.2*180+272

488 ten thousand yuan

It should be appreciated that the particular features, structures, materials, or characteristics described in this specification may be combined in any suitable manner in any one or more embodiments. Furthermore, the various embodiments and features of the various embodiments described in this specification can be combined and combined by one skilled in the art without contradiction.

Claims

1. Heating furnace superalloy cushion, characterized by: the chemical components by mass percent are as follows: 16-55% of Co, 10-35% of Cr, 10-30% of Ni, 2-5% of Al and the balance of Fe; the high-temperature alloy cushion block of the heating furnace is prepared by smelting and pouring in sequence, wherein the adding sequence of alloy elements during smelting is sequentially Ni, Cr and Co, and Al is added 3-5 minutes before molten alloy is discharged and poured.

2. The superalloy spacer for a furnace of claim 1, wherein: the chemical components by mass percent are as follows: 18-25% of Co, 14-23% of Cr, 15-24% of Ni, 2-5% of Al and the balance of Fe.

3. The superalloy spacer for a furnace of claim 1, wherein: the chemical components by mass percent are as follows: 48-55% of Co, 25-35% of Cr, 15-25% of Ni, 2-5% of Al and the balance of Fe.

4. The superalloy spacer for a furnace of claim 1, wherein: the smelting end point temperature is more than or equal to 1650 ℃.

5. The superalloy blocks of the furnace of claims 1 or 4, wherein: the smelting end point temperature is 100-300 ℃ higher than the highest melting point temperature of the added alloy.