What is ASTM A210 Grade C Tube?

The ASTM A210 Grade C is a seamless medium-carbon steel tube. It follows the ASTM A210 Grade C tube specification for superheater and boiler jobs. High temperatures and high pressures in 300MW or 600MW power stations need this material. It is a pearlitic hot-strong steel with great mechanical strength. Apart from being stronger, it has a higher carbon limit of 0.35% while Grade A1 only has 0.27%. We make these using a seamless process. They can be hot-finished or cold-finished to keep the walls even and the structure solid.

ASTM A210 Grade C Tube Specifications

This specification handles all the technical rules for high-strength boiler tubes.

Feature Detail
Standard ASTM A210/A210M, ASME SA210
OD Range 1/2" to 5" (12.7mm to 127mm)
Wall Thickness 0.035" to 0.500" (0.9mm to 12.7mm)
Schedules SCH20, SCH30, SCH40, STD, XH, SCH80, SCH100, SCH120, SCH140, SCH160, XXH
Length Single Random, Double Random, Cut Length (max 25m)
End Types Plain End, Beveled End, Threaded
Surface Finish Black, Varnished, Oiled, Pickled, Shot Blasted
Manufacture Hot-finished, Cold-finished

ASTM A210 Grade C Chemical Composition

The chemical composition given below focuses on higher carbon to get better strength

Element Content (%)
Carbon (C) 0.35 max
Manganese (Mn) 0.29 - 1.06*
Phosphorus (P) 0.035 max
Sulfur (S) 0.035 max
Silicon (Si) 0.10 min

*Note: If carbon drops by 0.01% below the max, manganese can go up by 0.06% above its max, reaching up to 1.35%.

ASTM A210 Grade C Mechanical Properties

These properties show that Grade C has 17% more tensile strength than Grade A1. It also has 8% more yield strength.

Property Value
Tensile Strength (min) 485 MPa (70,000 psi)
Yield Strength (min) 275 MPa (40,000 psi)
Elongation in 2" (min) 30%
Hardness (max) 89 HRB / 179 HB

Note: Mechanical rules do not apply to tubes smaller than 1/8 inch inside or 0.015 inch thick.

ASTM A210 Grade C Equivalent Standards

ASTM A210 Grade C tubes have the following equivalent designations across international standards systems:

Standard Equivalent
ASTM A210 Gr.C ASME SA210 Gr.C
DIN 17175 St45.8
EN 10216-2 P265GH
JIS G3461 STB410
BS 3059 Grade 360

Difference Between ASTM A210 Grade C and Grade A1

ASTM A210 Grade C offers enhanced mechanical properties compared to Grade A1. The A210 grade C vs grade A1 comparison shows significant differences in strength and application:

Property Grade C Grade A1
Carbon 0.35% max 0.27% max
Tensile Strength 485 MPa min 415 MPa min
Yield Strength 275 MPa min 255 MPa min
Hardness 89 HRB / 179 HB max 79 HRB / 143 HB max
Application High-strength, large capacity boilers General boiler applications

ASTM A210 Grade C Heat Treatment

Heat treatment requirements for ASTM A210 Grade C tubes depend on manufacturing method:

  • Hot-finished tubes: No heat treatment required
  • Cold-finished tubes must receive one of:
    • Subcritical anneal
    • Full anneal
    • Normalising heat treatment

Heat treatment is performed after the final cold finishing process and is critical for achieving the desired mechanical properties in SA 210 Gr C tubes.

ASTM A210 Grade C Tube Applications

These tubes are for high-strength needs in power and processing. Grade C vs Grade A1 shows that Grade C is better when Grade A1 cannot handle the stress.

Large Capacity Power Station Boilers

They are used in 300MW and 600MW plants. These tubes form water walls and economisers in supercritical boilers.

Superheater & Reheater Sections

High-temperature steam needs these. Grade C tubes manage steam temperatures that are near the limit of the metal.

High-Pressure Steam Systems

Steam headers, main steam lines, and high-pressure process piping where higher strength margins are needed beyond what Grade A1 provides for critical service reliability.

Chemical & Petrochemical Industries

High-pressure process heaters, reformer tubes, and waste heat recovery systems in refinery operations requiring tubes with enhanced mechanical properties.

Fertilizer Plants

Ammonia plant high-pressure systems, synthesis gas heaters, and steam generation equipment for ammonia production requiring high-strength tubing materials.

Nuclear Power Plants

They work in secondary steam systems and heat exchangers for safety.

Heat Exchangers & Condensers

Shell and tube exchangers operating under high pressure need this grade.

IBR Approved ASTM A210 Grade C Boiler Tubes

IBR (Indian Boiler Regulation) certification is mandatory for boiler applications in India. The IBR A210 grade C tube ensures safety, quality, and legal compliance for power station projects. Chhajed Steel Corporation supplies IBR certified A210 Grade C tubes with Form 3A/3D certification and third-party inspection by government-approved agencies.

Quality Testing & Certification

As per ASTM A210/A450, the following tests are mandatory. Special note for Grade C: Tears or breaks occurring at the 12 or 6 o'clock positions on Grade C tubing with sizes of 2.375 in. (60.3 mm) OD and smaller shall not be considered a basis for rejection during flattening test.

  • Tension Test: One test for lots up to 50 tubes; two tests for larger lots
  • Flattening Test: One test from each end of one finished tube per lot
  • Flaring Test: One test from each end of one finished tube per lot
  • Hardness Test: Brinell or Rockwell on two tubes per lot; max 89 HRB / 179 HB
  • Hydrostatic Test: Each tube tested or NDT as specified
  • IBR Certification (Form 3A/3D): IBR Certification (Form 3A/3D)
  • Govt. Lab Test Certificate (NABL Approved): Govt. Lab Test Certificate (NABL Approved)
  • EN 10204/3.1B Material Test Certificate (MTC): EN 10204/3.1B Material Test Certificate (MTC)
  • Third Party Inspection Report (TPI): Third Party Inspection Report (TPI)
  • 100% Radiography Test Report: 100% Radiography Test Report
  • Ultrasonic Test Report: Ultrasonic Test Report
  • PMI (Positive Material Identification): PMI (Positive Material Identification)

Frequently Asked Questions

  • What is ASTM A210 Grade C used for?

    The ASTM A210 Grade C is used for high-strength boilers. Big power stations of 300MW or 600MW use it for heating pipes and supercritical boilers.

  • What is the difference between SA210 Grade C and Grade A1?

    SA210 Grade C has higher carbon content (0.35% max vs 0.27% max), higher tensile strength (485 MPa vs 415 MPa), higher yield strength (275 MPa vs 255 MPa), and higher hardness limits (89 HRB vs 79 HRB). Grade C is used where higher strength is required.

  • When should I use Grade C instead of Grade A1?

    Use ASTM A210 Grade C when higher mechanical strength is required, such as in large capacity power station boilers (300MW+), high-pressure steam systems, and applications where design codes specify higher strength materials.

  • What is the maximum hardness for A210 Grade C?

    The maximum hardness for A210 Grade C is 89 HRB (Rockwell B) or 179 HB (Brinell Hardness).

  • Is ASTM A210 Grade C suitable for high temperature service?

    Yes, ASTM A210 Grade C is highly suitable for high-temperature, high-strength service in boilers and superheaters. It is classified as pearlitic hot-strong steel suitable for elevated temperature applications.