ASTM A351: Specification for Castings, Austenitic, for Pressure-Containing Parts

1. Scope*

1.1 ASTM A351 covers austenitic steel castings for valves, flanges, fittings, and other pressure-containing parts (Note 1).

NOTE 1—Carbon steel castings for pressure-containing parts are covered by Specification ASTM A216/A216M, low-alloy steel castings by Specification ASTM A217/A217M, and duplex stainless steel castings by Specification A995/A995M.

1.2 A number of grades of austenitic steel castings are included in this specification. Since these grades possess varying degrees of suitability for service at high temperatures or in corrosive environments, it is the responsibility of the purchaser to determine which grade shall be furnished. Selection will depend on design and service conditions, mechanical properties, and high-temperature or corrosion-resistant characteristics, or both.

1.2.1 Because of thermal instability, Grades CE20N, CF3A, CF3MA, and CF8A are not recommended for service at temperatures above 800 °F 425 °C.

1.3 Supplementary requirements of an optional nature are provided for use at the option of the purchaser. The Supplementary requirements shall apply only when specified individually by the purchaser in the purchase order or contract.

1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

1.4.1This specification is expressed in both inch-pound units and in SI units; however, unless the purchase order or contract specifies the applicable M-specification designation (SI units), the inch-pound units shall apply. Within the text, the SI units are shown in brackets or parentheses.

1.5This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

Chemical Requirement

Material Grade Element, % (max, except where range is given)
A351 UNS C Mn Si S P Cr Ni Mo Co V N Cu
CE20N J92802 0.20 1.50 1.50 0.040 0.040 23.0-26.0 8.0-11.0 0.50 ... ... 0.08-0.20 ...
CF3,CF3A J92700 0.03 1.50 2.00 0.040 0.040 17.0-21.0 8.0-12.0 0.50 ... ... ... ...
CF8, CF8A J92600 0.08 1.50 2.00 0.040 0.040 18.0-21.0 8.0-11.0 0.50 ... ... ... ...
CF3M, CF3MA J92800 0.03 1.50 1.50 0.040 0.040 17.0-21.0 9.0-13.0 2.0-3.0 ... ... ... ...
CF8M J92900 0.08 1.50 1.50 0.040 0.040 18.0-21.0 9.0-12.0 2.0-3.0 ... ... ... ...
CF3MN J92804 0.03 1.50 1.50 0.040 0.040 17.0-21.0 9.0-13.0 2.0-3.0 ... ... 0.10-0.20  
CF8C J92710 0.08 1.50 2.00 0.040 0.040 18.0-21.0 9.0-12.0 0.50 Note A   ... ...
CF10 J92950 0.04-0.10 1.50 2.00 0.040 0.040 18.0-21.0 8.0-11.0 0.50 ... ... ... ...
CF10M J92901 0.04-0.10 1.50 2.00 0.040 0.040 18.0-21.0 9.0-12.0 2.0-3.0 ... ... ... ...
CF10MC   0.10 1.50 2.00 0.040 0.040 15.0-18.0 13.0-16.0 17.5-22.5 Note B ... ... ...
CF10SMnN J92972 0.10 7.00-9.00 3.50-4.50 0.030 0.060 16.0-18.0 8.0-9.0 ... ... ... 0.08-0.18 ...
CG3M J92999 0.03 1.50 1.50 0.04 0.04 18.0-21.0 9.0-13.0 3.0-4.0 ... ... ... ...
CG6MMnN J93790 0.06 4.0-6.0 1.00 0.030 0.040 20.5-23.5 11.5-13.5 1.50-3.00 0.10-0.30 0.10-0.30 0.20-0.40  
CG8M J93000 0.08 1.50 1.50 0.04 0.04 18.0-21.0 9.0-13.0 3.0-4.0 ... ... ... ...
CH8 J93400 0.08 1.50 1.50 0.040 0.040 22.0-26.0 12.0-15.0 0.50 ... ... ... ...
CH10 J93401 0.04-0.10 1.50 2.00 0.040 0.040 22.0-26.0 12.0-15.0 0.50 ... ... ... ...
CH20 J93402 0.04-0.20 1.50 2.00 0.040 0.040 22.0-26.0 12.0-15.0 0.50 ... ... ... ...
CK20 J94202 0.04-0.20 1.50 1.75 0.040 0.040 23.0-27.0 19.0-22.0 0.50 ... ... ... ...
CK3MCuN J93254 0.025 1.20 1.00 0.010 0.045 19.5-20.5 17.5-19.5 6.0-7.0 ... ... 0.18-0.24 0.50-1.00
CN3MNN J94651 0.03 2.00 1.00 0.010 0.040 20.0-22.0 23.5-25.5 6.0-7.0 ... ... 0.18-0.26 0.75
CN7M N08007 0.07 1.50 1.50 0.040 0.040 19.0-22.0 27.5-30.5 2.0-3.0 ... ... ... 3.0-4.0
CT15C N08151 0.05-0.15 0.15-1.50 0.50-1.50 0.03 0.03 19.0-21.0 31.0-34.0 ... 0.50-150 ... ... ...
HG10MnN J92604 0.07-0.11 3.0-5.0 0.70 0.030 0.040 18.5-20.5 11.5-13.5 0.25-0.45 Note C ... 0.20-0.30 0.50
HK30 J94203 0.25-0.35 1.50 1.75 0.040 0.040 23.0-27.0 19.0-22.0 0.50 ... ... ... ...
HK40 J94204 0.35-0.45 1.50 1.75 0.040 0.040 23.0-27.0 19.0-22.0 0.50 ... ... ... ...
HT30 N08030 0.25-0.35 2.00 2.50 0.040 0.040 13.0-17.0 33.0-37.0 0.50 ... ... ... ...

Note
A - Grade CF8C shall have a columbium (niobium) content of not less than 8 times the carbon content but not over 1.00 %.
B - Grade CF10MC shall have a columbium (niobium) content of not less than 10 times the carbon content but not over 1.20 %.
C - Grade HG10MnN shall have a columbium (niobium) content of not less than 8 times the carbon, but not over 1.00 %.
D - Columbium (Cb) and niobium (Nb) are alternate names for Element 41

Physic Requirements (Tensile)

Material Grade Tensile strength, min Yield strength, min Elongation in 2 in.
or, 50 mm,  min,
A351 UNS ksi MPa ksi MPa  %
CE20N J92802 80 550 40  275 30
CF3 J92700 70 485 30 205 35
CF3A J92700 77 530 35 240 35
CF8 J92600 70 485 35 205 35
CF8A J92600 77 530 35 240 35
CF3M J92800 70 485 35 205 30
CF3MA J92800 80  550 37 255 30
CF8M J92900 70 485 30 205 30
CF3M J92804 75 515 37 255 35
CF8C J92710 70 485 30 205 30
CF10 J92950 70 485 30 205 35
CF10M J92901 70 485 30 205 30
CF10MC   70 485 30 205 20
CF10SMnN J92972 82 585 42.5 295 30
CG3M J92999 75 515 35 240 25
CG6MMnN J93790 85 585 42.5 295 30
CG8M J93000 75 515 35 240 25
CH8 J93400 65 450 28 195 30
CH10 J93401 70 485 30 205 30
CH20 J93402 70 485 30 205 30
CK20 J94202 65 450 28 195 30
CK3MCuN J93254 80 550 38 260 35
CN3MNN J94651 80 550 38 260 35
CN7M N08007 62 425 25 170 35
CT15C N08151 63 435 25 170 20
HG10MnN J92604 76 525 33 225 20
HK30 J94203 65 450 35 240 10
HK40 J94204 62 425 35 240 10
HT30 N08030 65 450 28 195 15

A - Determine by the 0.2 % offset method.
B - When ICI test bars are used in tensile testing as provided for in Specification A995/A995M, the gauge length to reduced section diameter ratio shall be 4 to 1.

Leave Us Your Info

Could you please kindly fulfill the following information when enquiring:

Valve type (ball, gate, globe, check etc.), valve size, pressure class, valve material, and end connection (flanged, butt welding etc.)