ASTM A278/A278M-01(2020)

Standard Specification for Gray Iron Castings for Pressure-Containing Parts for Temperatures Up to 650 °F (350 °C)

ABSTRACT
This specification covers gray iron for castings suitable for pressure-containing parts at elevated temperatures. Castings shall be stress-relieved by placing them in a suitable furnace and heating them uniformly to the temperatures and for the times specified. Castings to be used at a particular temperature range shall undergo heat treatment and cooling. Chemical analysis shall be performed on each class of castings and shall meet the maximum requirement for carbon, phosphorus and sulfur. Iron used in supplying castings shall conform to the required tensile strength. Separately cast test bars having the required dimensions shall be poured from the same lot as the castings represented. The test bars shall be cast in dried siliceous sand molds maintained at approximately room temperature. Tension test shall be performed on each lot and materials shall conform to the tensile requirements specified.
SCOPE
1.1 This specification2 covers gray iron for castings suitable for pressure-containing parts for use at temperatures up to 650 °F (350 °C).  
1.2 Classes of Iron:  
1.2.1 Castings of all classes are suitable for use up to 450 °F (230 °C). For temperatures above 450 °F and up to 650 °F, only Class 40, 45, 50, 55, and 60 castings are suitable.  
1.2.2 Castings of all classes are suitable for use up to 230 °C. For temperatures above 230 °C and up to 350 °C, only Class 275, 300, 325, 350, 380, and 415 castings are suitable.  
1.3 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 nonconformance with the standard.  
1.4 This 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.

General Information

• Status: Published
• Publication Date: 30-Apr-2020
• ICS: 77.140.80 - Iron and steel castings
• Technical Committee: A04 - Iron Castings
• Drafting Committee: A04.01 - Grey and White Iron Castings

Relations

• Replaces: ASTM A278/A278M-01(2015) - Standard Specification for Gray Iron Castings for Pressure-Containing Parts for Temperatures Up to 650°F (350°C)
• Effective Date: 01-May-2020
• Refers: ASTM E8/E8M-24 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 01-Jan-2024
• Refers: ASTM A644-17 - Standard Terminology Relating to Iron Castings
• Effective Date: 01-Nov-2017
• Refers: ASTM E8/E8M-16 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 15-Jul-2016
• Refers: ASTM E8/E8M-15 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 01-Feb-2015
• Refers: ASTM A644-14 - Standard Terminology Relating to Iron Castings
• Effective Date: 01-Oct-2014
• Refers: ASTM E8/E8M-13 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 01-Jun-2013
• Refers: ASTM A644-13 - Standard Terminology Relating to Iron Castings
• Effective Date: 01-May-2013
• Refers: ASTM E8/E8M-11 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 01-Dec-2011
• Refers: ASTM A644-09a - Standard Terminology Relating to Iron Castings
• Effective Date: 01-Jul-2009
• Refers: ASTM A644-09 - Standard Terminology Relating to Iron Castings
• Effective Date: 01-Jun-2009
• Refers: ASTM A644-05 - Standard Terminology Relating to Iron Castings
• Effective Date: 01-Nov-2005
• Refers: ASTM A644-98(2003) - Standard Terminology Relating to Iron Castings
• Effective Date: 10-Dec-1998
• Referred By: ASTM F1545-15a(2021) - Standard Specification for Plastic-Lined Ferrous Metal Pipe, Fittings, and Flanges
• Effective Date: 01-May-2020
• Referred By: ASTM A834-95(2020) - Standard Specification for Common Requirements for Iron Castings for General Industrial Use
• Effective Date: 01-May-2020

Overview

ASTM A278/A278M-01(2020), Standard Specification for Gray Iron Castings for Pressure-Containing Parts for Temperatures Up to 650°F (350°C), sets forth the essential requirements for gray iron castings used in pressure-containing components designed for elevated temperature service. Developed by ASTM International, this standard is widely utilized in industries where gray iron is selected for its mechanical properties and cost-effectiveness. Ensuring reliable performance under temperatures up to 650°F (350°C), the specification covers chemical composition, tensile strength, heat treatment, testing, and quality requirements, providing a foundation for manufacturing and procurement of compliant castings.

Key Topics

• Material Classes and Temperature Ranges

  • Castings of all classes are suitable for use up to 450°F (230°C).
  • For applications exceeding 450°F (230°C) and up to 650°F (350°C), only specific classes (Class 40, 45, 50, 55, and 60 in inch-pound; Class 275, 300, 325, 350, 380, and 415 in SI units) are permitted.

• Mechanical Properties

  • Gray iron castings are classified based on minimum tensile strength.
  • Each class ensures castings meet the required strength for pressure containment at elevated temperatures.
  • Maintaining precise tensile strength is critical for safety and regulatory compliance.

• Chemical Requirements

  • Maximum limits for carbon equivalent (3.8%), phosphorus (0.25%), and sulfur (0.12%) are enforced to ensure durability and performance.
  • Chemical analysis is performed per batch to confirm compliance.

• Heat Treatment and Stress Relief

  • Stress-relieving heat treatment is required for castings destined for higher-temperature applications.
  • Temperature and holding time are specified based on casting class and section thickness.
  • Proper heat treatment and controlled cooling promote dimensional stability and reduce internal stresses.

• Testing and Quality Control

  • Tension testing is mandatory for each production lot using separately cast or integral test bars.
  • Test bars must be cast in controlled sand molds and undergo specific machining and testing procedures.
  • Quality acceptance criteria include surface integrity and conformity to specified dimensions.

• Marking and Certification

  • Castings must be marked with manufacturer identification and class information.
  • Certification of compliance and testing results is required upon request.

Applications

ASTM A278/A278M-compliant gray iron castings are prominent in:

• Pressure Vessels: Used for components such as pump housings, valve bodies, and pressure-retaining pipes.
• Industrial Boilers: Suited for water, steam, and gas containment in boiler assemblies operating below 650°F (350°C).
• Pipe Fittings and Flanges: Ensures structural integrity in high-pressure pipelines and coupling systems.
• Machinery Components: Applies to compressor casings, heat exchanger shells, and other machinery requiring strong, temperature-tolerant cast iron parts.

The specification provides material engineers and manufacturers with guidelines for producing safe, durable, and high-performance gray iron castings in demanding operational environments.

Related Standards

• ASTM A644: Terminology Relating to Iron Castings - provides standardized definitions important for procurement and specification.
• ASTM E8/E8M: Test Methods for Tension Testing of Metallic Materials - referenced for tension test protocols.
• ASME SA-278: Specification for Gray Iron Castings for Pressure-Containing Parts (Boiler and Pressure Vessel Code) - harmonized for code compliance in regulated industries.

For more information or to access the full standard, refer to the ASTM International website.

Keywords: ASTM A278, gray iron castings, pressure-containing parts, elevated temperature service, tensile strength, heat treatment, industrial standards, mechanical properties, pressure vessel components

Standards Content (Sample)

This 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.
Designation:A278/A278M −01 (Reapproved 2020)
Standard Specification for
Gray Iron Castings for Pressure-Containing Parts for
Temperatures Up to 650°F (350°C)
This standard is issued under the fixed designationA278/A278M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope 3. Terminology
1.1 This specification covers gray iron for castings suitable 3.1 Definitions of many terms common to gray iron castings
for pressure-containing parts for use at temperatures up to may be found in Terminology A644.
650 °F (350 °C).
4. Classification
1.2 Classes of Iron:
4.1 Classification by tensile strength.
1.2.1 Castings of all classes are suitable for use up to 450 °F
4.1.1 Castings ordered to this specification are classified
(230 °C). For temperatures above 450 °F and up to 650 °F,
based upon the minimum tensile strength of the iron in ksi, in
only Class 40, 45, 50, 55, and 60 castings are suitable.
English units. Class 25 has a minimum specified tensile
1.2.2 Castings of all classes are suitable for use up to
strength of 25 ksi.
230 °C. For temperatures above 230 °C and up to 350 °C, only
4.1.2 Castings ordered to this specification are classified
Class 275, 300, 325, 350, 380, and 415 castings are suitable.
based upon the minimum tensile strength of the iron in MPa, in
1.3 The values stated in either SI units or inch-pound units
Metric units. Class 150 has a minimum specified tensile
are to be regarded separately as standard. The values stated in
strength of 150 MPa.
each system may not be exact equivalents; therefore, each
system shall be used independently of the other. Combining
5. Ordering Information
values from the two systems may result in nonconformance
5.1 Orders for material in this specification should include
with the standard.
the following information:
1.4 This international standard was developed in accor-
5.1.1 ASTM designation and year date,
dance with internationally recognized principles on standard-
5.1.2 Class of iron required and service temperature,
ization established in the Decision on Principles for the
5.1.3 Quantity,
Development of International Standards, Guides and Recom-
5.1.4 Heat Treatment:
mendations issued by the World Trade Organization Technical
5.1.4.1 Whether or not heat treatment is required for Class
Barriers to Trade (TBT) Committee.
40, 45, 50, 55, and 60 castings to be used at temperatures at
450 °F or less (see 6.2),
2. Referenced Documents
5.1.4.2 Whether or not heat treatment is required for Class
2.1 ASTM Standards:
275, 300, 325, 350, 380, and 415 castings to be used at
A644 Terminology Relating to Iron Castings
temperatures at 230 °C or less (see 6.2),
E8/E8M Test Methods for Tension Testing of Metallic Ma-
5.1.5 The size of separately cast test bar to be poured (see
terials
Section 9 and Table 1),
5.1.6 The size of test specimen to be machined from test
barsCorS,and
This specification is under the jurisdiction of ASTM Committee A04 on Iron
5.1.7 Special requirements.
CastingsandisthedirectresponsibilityofSubcommitteeA04.01onGreyandWhite
Iron Castings.
6. Materials and Manufacture
Current edition approved May 1, 2020. Published May 2020. Originally
approved in 1944. Last previous edition approved in 2015 as A278/
6.1 Castings intended for use above 450 °F (230 °C) shall
A278M – 01 (2015). DOI: 10.1520/A0278_A0278M-01R20.
be stress-relieved by placing them in a suitable furnace at a
For ASME Boiler and Pressure Vessel Code applications, see related Specifi-
cation SA-278 in Section II of that Code.
temperature not exceeding 400 °F (200 °C) and heating them
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
uniformly to the temperatures and for the times specified in
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Table 2. The heating and cooling rates shall be uniform and
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. shallnotbemorethan400 °F⁄h(250 °C⁄h)forcastingsof1-in.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A278/A278M−01 (2020)
TABLE 1 Diameters and Lengths of Cast Test Bars
8. Tensile Requirements
As-Cast Diameter, in. (mm) Length, in. (mm)
8.1 Iron used in supplying castings to this specification shall
Test
Minimum Maximum Minimum Maximum
Bar
conform to the tensile requirements prescribed in Tables 3 and
(Bottom) (Top) (Specified) (Recommended)
4.
A 0.88 (23) 0.85 (22) 0.96 (25) 5.0 (125) 6.0 (1.50)
B 1.20 (33) 1.14 (32) 1.32 (36) 7.0 (150) 9.0 (230)
C 2.00 (54) 1.90 (53) 2.10 (58) 6.0 (175) 10.0 (255)
9. Test Bars
A
S
9.1 Separatelycasttestbarshavingthedimensionsshownin
A
All dimensions of Test Bar S shall be agreed upon by the manufacturer and the
Table 1 shall be poured from the same lot as the castings
purchaser.
represented. The size of the test bar to be poured shall be
selected by the purchaser using Table 5. In the event no choice
TABLE 2 Stress-Relieving Requirements
is made, the selection will be made by the manufacturer.
A
Class Metal Temperature, °F Holding Time, h
9.2 Separately cast test bars shall be heat treated in the same
(°C)
furnace together with the castings represented.
40, 45, 50, 55, 60 1050 to 1200 2 12
B B
(275, 300, 325, 350, (565 to 650) (2 min) (12 max)
9.3 At the option of the manufacturer, test coupons may be
380, 415)
removed from the casting at a location agreed upon between
A
In no case shall the holding time be less than 1 h/in. of maximum metal section,
the manufacturer and purchaser.
or in excess of 12 h max, dependent upon which governs.
B
In no case shall the holding time be less than1hfor every 25-mm metal section,
9.4 Castings weighing in excess of 2000 lb may be repre-
or in excess of 12 h max, depending upon which governs.
sented either by separately cast test bars (9.1) or by integrally
cast test bars having a cooling rate closely approximating that
of the controlling section of the casting.
9.5 For castings weighing in excess of 10 000 lb or having
(25-mm) maximum section. For heavier sections, the maxi-
a controlling section greater than 2 in., test bars may be
mum heating and cooling rates in degrees Fahrenheit per hour
removed from the casting or integral projections having a cross
shall be 400 divided by the maximum section thickness.
section no less than the controlling section. The minimum
6.2 Heat Treatment and Cooling Rate: tensile strength requirement for tension tests performed on
either of these test bars shall be 80 % of the specified class.
6.2.1 CastingsofClassNos.45,50,55,and60,whichareto
be used at temperatures below 450 °F, may be heat treated in
accordance with 6.1 or they shall be cooled in the mold to 10. Molding and Pouring Test Bars
500 °F at an average rate of not more than 100 °F⁄h for
10.1 The test bars shall be cast in dried siliceous sand molds
castings up to 1 in. in section. For heavier sections, the
maintained at approximately room temperature. A suitable
maximum cooling rate in degrees Fahrenheit per hour shall be
design for a mold is shown in Fig. 1.
100 divided by the maximum section thickness.
6.2.2 Castings of Class Nos. 275, 300, 325, 350, 380, and
11. Workmanship, Finish, and Appearance
415, which are to be used at temperatures below 230 °C, may
11.1 All castings shall be made in a workmanlike manner
be heat treated in accordance with 6.1 or they shall be cooled
and shall conform to the dimensions on drawings furnished by
in the mold to 250 °C at an average rate of not more than
the purchaser. If the pattern is supplied by the purchaser
50 °C⁄h for castings up to 25 mm in section.
...