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China National Standard-Cast Iron Stave Cooler YB/T 4073-2007(1)

YB

Black Metallurgical Industry Standard of the PRC

YB/T 40732007

Replace YB/ T 4073 1991


Cast Iron Stave for Blast Furnace

PS: This article is translated according to YBT4073-2007. As far as possible to respect the content of the original text, for reference only. There are deficiencies please contact us to correct, thank you for your suggestion. This article is longer and will be published in 3 articles, so stay tuned. To download, please contact our staff


Preface

This standard replaces YB/T 4073-1991 “Cast Iron Stave for Blast Furnace”.

This standard has the following important differences with the YB/T4073-1991 standard:

——This standard increases the main technical parameters of the material, variety and performance of the cast iron cooling stave;

——Focusing on the characteristics of thick section and high-toughness ductile cast iron cooling stave, meanwhile, mainly based on the attached test block and physical properties, the standard increase the technical requirements of Appendix B "Standard Inspection of Stave Cooler";

 

——This standard emphasizes the anti-carburization treatment and inspection of the cast iron cooling stave casting into the cooling water pipe, and increases the technical requirements of Appendix A “Cooling Water Pipe Anti-carburization Inspection”;

——The inspection and acceptance rules for the stave cooler products have been improved.

Appendix A of the standard is a normative appendix, and Appendix B is an informative appendix.

The standard is proposed by the China Iron and Steel Industry Association.

The standard is under the jurisdiction of the Metallurgical Electromechanical Standardization Technical Committee.

The standard drafted by: Angang Heavy Machinery Co., Ltd. (formerly Angang Group Machinery Manufacturing Company).

 

The main drafters of the standard: Jiang Yanqi, Xie Changfa, Song Enyu.

The previous version of the standard replaced by this standard is:

——YB/ T 4073- 1991

Cast Iron Stave for Blast Furnace

1.      Range

The standard specifies the technical requirements, test methods, inspection rules, quality certificates, signs, packaging and transportation of cast iron cooling stave for blast furnace (grey cast iron, ductile cast iron stave).

This standard is applicable to cast iron staves for ironmaking blast furnaces of various volumes. If specially required, it can be specified in the drawings or special technical documents.

2.      Normative reference file

The terms in the following documents become the terms of the standard by reference to it. All subsequent amendments to the date of the note (excluding errata content) or the revised version do not apply to this standard, however, parties that agree upon this standard are encouraged to study whether the latest version of these documents can be used. The latest version of any reference file that does not note the date applies to this standard.

GB/T 223. 5 Methods for chemical analysis of steels and alloys - Determination of acid-soluble silicon content by reduced silicomolybdate photometric method

GB/T 223. 46 Methods for chemical analysis of steels and alloys - Determination of magnesium content by flame atomic absorption spectrometry

GB/T 223. 49 Methods for chemical analysis of steels and alloys - Extraction separation - chlorophosphonazo mA spectrophotometric method for determination of total rare earth

GB/T 223. 58 Methods for chemical analysis of steels and alloys - Sodium arsenite - Sodium nitrite titration to determine the magnitude of the mammoth

GB/T 223. 62 Methods for chemical analysis of steels and alloys - Determination of phosphorus content by butyl acetate extraction spectrophotometry

GB/T 223. 68 Steel and alloy chemical analysis method --Determination of sulfur content by potassium iodate titration after combustion in tubular furnace

GB/T 223. 69 Chemical analysis methods for steel and alloys --Determination of carbon content by gas volume method after combustion in tubular furnace

GB/T 228 Metallic materials Room temperature test method (GB/T 228-2002 eqv ISO 6892:1998(E))

GB/T229 metal Charpy notched impact test method (GB/T 229-1994 eqv ISO 148:1983)

GB/T231.1 Metallic Brinell hardness test Part 1: Test method (GB/T 231. 1-2002 eqv ISO 6506-1:1 999(E))

GB/T 699 high quality carbon structural steel

GB/T 1348 ductile iron castings

GB 3087 Seamless steel pipe for low and medium pressure boilers (GB 3087—1999 NEQ ISO 9329—1:1989)

GB/T 6060. L-1 997 Surface roughness comparison specimen Casting surface (eqv ISO 2632-3:1979)

GB/T 6414-1999 Casting dimension tolerances and machining margin (eqv ISO 8062:1994)

GB/T 7216 gray cast iron metallurgy (GB/T 7216-1 987 neq ISO 945:1975)

GB/T 8163 seamless steel pipes for conveying fluid (GB/T 8163-1999 neq ISO 559:1991)

GB/T 9439 gray iron castings

GB/T 9441 Ductile Iron Metallographic Examination

JB/T 7945 Test method of mechanical properties of gray cast iron

3.      Product Categories

3.1 Classificated according to the form of cast iron stave cooler’s structure: glossy stave cooler, brick-paneled stave cooler and mash-type stave cooler.

3.2 Classificated according to the cast iron stave cooler’s cooling water pipe: single-row pipe stave cooler, double-row pipe stave cooler and multi-row pipe stave cooler.

3.3 Classificated according to the material of cast iron stave cooler body: gray cast iron stave and ductile iron stave.

4.      Technical requirements

4.1 The body of the cast iron stave cooler for blast furnace can be made of gray cast iron or ductile iron, which can be negotiated and determined if required by the purchaser.

The mechanical properties should conform to the requirements of Tables l and Table 2, and the impact value sits in Table 3.

Table 1 Mechanical properties of single test bar(rods) of casting

 

 

Grade

Rm

tensile strength

N/mm2

Rel

Yield Strength

N/mm2

A

Elongation

 For   

inference

HBW

Major metallographic   organization

HTl50

150

——

——

——

——

HT200

200

——

——

——

——

QT400-18

≥400

≥250

≥18

130~180

Ferrite

QT400-20

≥400

≥250

≥20

130~180

Ferrite

Table 2 Mechanical properties of casting test lug 

 

 

Grade

 

Stave cooler

thickness

mm

Rm

tensile   strength

N/mm2

Rel

Yield

Strength

N/mm2

A

Elongation

For inference

HEW

Major metallographic organization

 

QT400-18A

 

 

>60~200

 

≥370

 

≥240

 

≥12

 

 

130~180

 

 

Ferrite

 

QT400-20A

 

 

≥14

Note: The blast furnaces above 1000m3 are   

all equipped with casting test lugs.

Table 3 Impact value of specimens of test lug(V-notch)

 (room temperature 23 soil 5)

 

Grade

 

thickness

mm

Impact energy Akv, J

Average of three samples

Individual value

QT400-18A

>60~200

≥12

≥9

QT400-20A

>60~200

≥12

≥9

4.2 The metallographic structure of the cast iron stave for blast furnaces shall meet the requirements of Table 4.

Table 4 Metallographic organization

 

Grade

 

Graphite form

 

Spheroidization grade (spheroidization rate)

 

Graphite size

 

Ferrite

 

HT150

HT200

Flakes

Types A, B, and C


Grade 3 to 6


QT400-18

QT400-20

Balls+ small groups

Grade 3 or higher

(> 80%)

Grade 5 to 8

>90



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