Carbon steel pipes are widely used across industries for their strength, reliability and cost-effectiveness. In order to select the right product, you must understand the various steel grades of carbon steel pipes and how they differ. This article explains typical grade classifications, key standards, application zones and selection recommendations.
Why Steel Grade Matters for Carbon Steel Pipes
When specifying carbon steel pipes, the steel grade defines strength, toughness, weldability and durability. A higher grade may mean higher yield strength and better performance under pressure. However, trade-offs in weldability or cost can apply. Therefore, selecting a suitable steel grade for your piping system ensures safety, cost-efficiency and long-term reliability. For industries such as oil & gas, refining and power generation, correct grade choice is critical.
Common Steel Grades and Standards for Carbon Steel Pipes
The most commonly referenced standards and grades for carbon steel pipes include:
ASTM A53 Grade A and B. – widely used for general purpose water, gas and low-temperature service.
ASTM A106 Grade B (and sometimes Grade C). – used for seamless carbon steel pipes intended for high temperature service.
ASTM A333 Grade 1, 3, 6 – used for low‐temperature carbon steel pipes.
API 5L Grades B, X42, X52, X60, X65 etc – used for line pipe conveying oil, gas and water.
Other standards: ASTM A179, ASTM A192 etc for boiler and heat-exchanger tubes.
Common ASTM Steel Grades for Carbon Steel Pipes
Why Steel Grade Matters for Carbon Steel Pipes
When specifying carbon steel pipes, the steel grade defines strength, toughness, weldability and durability. A higher grade may mean higher yield strength and better performance under pressure. However, trade-offs in weldability or cost can apply. Therefore, selecting a suitable steel grade for your piping system ensures safety, cost-efficiency and long-term reliability. For industries such as oil & gas, refining and power generation, correct grade choice is critical.
Common Steel Grades and Standards for Carbon Steel Pipes
The most commonly referenced standards and grades for carbon steel pipes include:
ASTM A53 Grade A and B. – widely used for general purpose water, gas and low-temperature service.
ASTM A106 Grade B (and sometimes Grade C). – used for seamless carbon steel pipes intended for high temperature service.
ASTM A333 Grade 1, 3, 6 – used for low‐temperature carbon steel pipes.
API 5L Grades B, X42, X52, X60, X65 etc – used for line pipe conveying oil, gas and water.
Other standards: ASTM A179, ASTM A192 etc for boiler and heat-exchanger tubes.
Common ASTM Steel Grades for Carbon Steel Pipes
| ASTM Grade | Type / Manufacturing Method | Main Application / Description |
| A53 | Welded and Seamless Carbon Steel Pipe | For ordinary uses such as water, gas, and steam lines. |
| A106 | Seamless Carbon Steel Pipe | For high-temperature service. |
| A161 | Seamless Low-Carbon and Carbon-Molybdenum Steel Pipe | For refinery service, distillation tubes. |
| A178 | Electric-Resistance-Welded Carbon Steel Tube | For boilers, superheaters, and heat exchangers. |
| A179 | Seamless Cold-Drawn Low-Carbon Steel Tube | For heat exchangers and condensers. |
| A134 | Electric-Fusion (Arc) Welded Steel Pipe | 16 inches and over in diameter. |
| A192 | Seamless Carbon Steel Boiler Tube | For high-pressure service. |
| A135 | Electric-Resistance-Welded Steel Pipe | For conveying gas, vapor, water, or other liquids. |
| A199 | Seamless Cold-Drawn Intermediate Alloy Steel Tube | For heat exchangers and condensers. |
| A139 | Electric-Fusion (Arc) Welded Steel Pipe | 4 inches and larger, for pressure and structural purposes. |
| A200 | Seamless Intermediate Alloy Steel Pipe | For refinery service, distillation tubes. |
| A209 | Seamless Carbon-Molybdenum Alloy Steel Tube | For boilers and superheaters. |
| A210 | Seamless Medium-Carbon Steel Tube | For boilers and superheaters. |
| A211 | Spiral-Welded Steel Pipe | For general engineering and pressure service. |
| A213 | Seamless Ferritic and Austenitic Alloy Steel Tube | For boilers, superheaters, and heat exchangers. |
| A214 | Electric-Resistance-Welded Carbon Steel Tube | For heat exchangers and condensers. |
| A226 | Electric-Resistance-Welded Carbon Steel Tube | For high-pressure boilers and superheaters. |
| A250 | Electric-Resistance-Welded Carbon-Molybdenum Alloy Steel Tube | For boilers and superheaters. |
| A252 | Welded and Seamless Steel Pipe Piles | For structural and piling applications. |
| A254 | Copper-Brazed Steel Tube | For automotive and refrigeration applications. |
| A333 | Seamless and Welded Steel Pipe | For low-temperature service. |
| A334 | Seamless and Welded Carbon and Alloy Steel Pipe | For low-temperature applications. |
| A335 | Seamless Ferritic Alloy Steel Pipe | For high-temperature service. |
| A370 | Test Methods and Definitions for Steel Products | Describes mechanical testing requirements. |
| A381 | Metal-Arc-Welded Steel Pipe | For high-pressure transmission service. |
| A405 | Seamless Ferritic Alloy Steel Pipe | For high-temperature service with special heat treatment. |
| A422 | Butt-Welded Steel Tube | For refinery guided-wave applications. |
| A423 | Seamless and Welded Low-Alloy Steel Pipe | For general industrial and pressure service. |
| A450 | General Requirements for Carbon and Alloy Steel Pipe | Covers standard manufacturing and inspection rules. |
| A498 | Seamless and Welded Carbon, Ferritic, and Austenitic Alloy Steel Tube | With integral fins for heat exchangers. |
| A500 | Welded and Seamless Cold-Formed Carbon Steel Structural Tube | For structural applications, round or shaped sections. |
| A501 | Hot-Formed Welded and Seamless Carbon Steel Structural Tube | For structural use at moderate temperatures. |
| A512 | Cold-Drawn Butt-Welded Carbon Steel Mechanical Tube (CDBW) | For mechanical use; Grades 1010, 1012, 1020. |
| A513 | Electric-Resistance-Welded Carbon and Alloy Steel Mechanical Tube (ERW-DOM) | For mechanical use; DOM supplied as 1020 or 1026 grades. |
| A519 | Seamless Carbon and Alloy Steel Mechanical Tube (CDS or HFS) | For mechanical use; common grades include 1016, 1026, 4130, 4140. |
| A520 | Supplementary Requirements for Seamless and ERW Carbon Steel Pipe | For high-temperature boiler applications. |
| A523 | Plain-End Seamless Electric-Resistance-Welded Steel Pipe | For high-pressure pipe-type cable circuits. |
| A524 | Seamless Carbon Steel Pipe | For ordinary fluid service and low-temperature use. |
| A530 | General Requirements for Specialized Carbon and Alloy Steel Pipe | For additional testing and dimensional requirements. |
| A539 | Electric-Resistance-Welded Steel Pipe | For natural gas and fuel oil pipelines. |
| A556 | Seamless Cold-Drawn Carbon Steel Tube | For feedwater heaters. |
| A557 | Electric-Resistance-Welded Carbon Steel Tube | For feedwater heaters. |
| A587 | Electric-Resistance-Welded Carbon Steel Pipe | For chemical process piping. |
| A589 | Seamless |
