Representation of cast steel grades for German, Russian, American and British standard valves (1)

Representation of cast steel grades for German, Russian, American and British standard valves (1)

1. International Organization for Standardization (so)

ISO / dp3755-1983 "general engineering cast carbon steel" (Draft), cast steel is divided into three grades according to strength. his

The grade is represented by two groups of three digits, the former is the yield strength (MPA), the latter is the tensile strength (MPA), such as

230-450。 Only the upper limit of each element content is specified for chemical composition, and the specific composition is determined by the foundry.

The draft standard of high strength cast steel for general engineering and structure has been formulated in 1991

Except for the upper limit of Si, P and s, the content of carbon and other elements in cast iron is determined by

The manufacturer chooses by itself.

2. DIN (SEW)

All carbon cast steel and low alloy cast steel are crowned with GS.

General steel castings (din1681) are graded according to the strength, and two groups of numbers are added after GS, such as GS - ×× - ×

The group numbers represent the yield strength and the latter group represent the tensile strength, which is close to the ISO standard. Casting with good weldability is required

Steel and alloy steel are represented by chemical composition.

3. American national standard (ANSI / ASTM)

Carbon steel castings for general engineering (ANSI / ASTM a27), high strength steel structural castings (ANSI / ASTM a148)

The steel castings for highway bridges (ANSI / ASTM a486) are classified according to the strength, which is similar to ISO standard.

The nomenclature of American Alloy Casting Association (ACD) is adopted for high alloy cast steel.

The first letter is C or h, C for corrosion resistance and h for heat resistance. The second letter indicates the alloy content, from a to

Z means that n increases. For example, a-cr12%, f-cr19% Ni9%, hcr25% - Ni12%, Z

Ni100%。 The third letter is the carbon content of steel × 100, which is the maximum in "C" system and flat in "H" system

Mean value. For example, cf-8 contains c0.08% (maximum), cr19% and Ni9%. HK40, i.e. c0.40%

Cr25% and Ni2%. The fourth letter or letters indicate the content of alloying elements, such as the chemical composition of cf-3m

The alloy code of American ACI standard is: m-mo, mn-m

N-ni or N, c-a1, Cu Cu. For example, ca6nm is basically equivalent to zg06cr13 in China

N14Mo。 Benzene,

4. UK (BS)

There are two series of cast steel in England, namely bs3100 and bs1504

Bs3100 is a steel casting for general engineering

Carbon steel or low manganese steel is divided into six grades A1 ~ A6 according to the strength (increasing strength).

There are 11 kinds of low temperature steel added with L after a

There are 33 kinds of surface hardened wear-resistant steels, aw1-aw33, after a and W

There are 22 kinds of AM1 and am22.

Low alloy steel is divided into 6 grades according to strength, B1 ~ B6 (increasing strength).

The grade of chromium molybdenum vanadium steel for high temperature is B7;

There are BL1 and bl22 kinds of ferritic steel for low temperature service

There are 33 kinds of bt1-bt33 high strength alloy steels with t added after B;

The wear-resistant cast steel is added with W after B: surface solution fire cast steel bw1, wear-resistant low chromium steel BW2 ~ bw4, austenitic manganese steel BW10.