ASTM A312 (ASME SA312) is the standard specification for seamless welded and heavily cold-worked austenitic stainless steel pipes used in high-temperature corrosive and general industrial service. The specification defines the manufacturing process chemical composition mechanical properties dimensions testing and inspection requirements to ensure consistent quality and reliable performance.
ASTM A312 covers a wide range of stainless steel grades including TP304 TP304L TP316 TP316L TP321 TP347 TP310S and TP904L. These pipes are manufactured to provide excellent corrosion resistance high mechanical strength weldability and durability making them suitable for demanding pressure piping systems and aggressive operating environments.
ASTM A312 stainless steel pipes are widely used in oil and gas petrochemical chemical processing power generation food processing pharmaceutical water treatment marine and offshore industries. Kamal Steels supplies ASTM A312 pipes in various grades sizes schedules and end finishes with Mill Test Certificates (EN 10204 3.1) third-party inspection and customized project requirements for domestic and international applications.
ASTM A312 Stainless Steel Pipe Specification
Specification
Details
Standard
ASTM A312 / ASME SA312
Pipe Type
Seamless, Welded, ERW, EFW, Heavy Cold‑Worked
Size Range
1/8" NB to 24" NB
Schedule
SCH 5S to XXS (SCH 160 / XXS)
Length
Single random, Double random, Cut length
End
Plain, Bevel, Threaded
Popular ASTM A312 Pipe Grades
Grade
Features
TP304 / TP304L
General corrosion resistance; TP304L for improved weldability.
TP316 / TP316L
Improved chloride and pitting resistance; TP316L for welded systems.
TP321 / TP347
Stabilized grades for elevated-temperature service.
TP310S
High temperature/oxidation resistance.
TP904L
High-alloy for aggressive corrosive environments.
TP304 vs TP316 – Quick Comparison
Grade
Best Choice For
TP304
General corrosion resistance is needed at lower cost; good for indoor process lines and food processing where chlorides are low.
TP316 / TP316L
Chloride, marine, or pitting resistance is critical; TP316L reduces carbide precipitation in welded systems.
Key Difference
TP316 adds molybdenum (2–3%) for superior chloride resistance; TP316L has lower carbon for weldability.
We stock ASTM A312 TP304, TP304L, TP316 and TP316L pipes in common sizes and schedules, all supplied with Mill Test Certificates (EN 10204 3.1). To receive a quotation, simply provide the required grade, NPS, schedule, length or quantity, and destination. Urgent orders are available from our Mumbai warehouse with fast dispatch for domestic and international export requirements.
Types of ASTM A312 Stainless Steel Pipes
Pipe Type
Description
Seamless Pipe
Used where strength and pressure performance are important.
Welded Pipe
Common choice for general industrial piping.
ERW Pipe
Manufactured using electric resistance welding for consistent quality and dimensional accuracy.
Electric Fusion Welded (EFW) Pipe
Suitable for larger sizes and corrosive service.
Heavy Cold Worked Pipe
Used where tighter dimensional control and enhanced mechanical properties are required.
ASTM A312 Chemical Composition
Grade
Carbon (C)
Chromium (Cr)
Nickel (Ni)
Molybdenum (Mo)
TP304
0.08 Max
18.0 – 20.0%
8.0 – 11.0%
—
TP304L
0.035 Max
18.0 – 20.0%
8.0 – 12.0%
—
TP316
0.08 Max
16.0 – 18.0%
10.0 – 14.0%
2.0 – 3.0%
TP316L
0.035 Max
16.0 – 18.0%
10.0 – 14.0%
2.0 – 3.0%
ASTM A312 Mechanical Properties
Grade
Tensile Strength (MPa)
Yield Strength (MPa)
Elongation (%)
TP304
515 Min
205 Min
35 Min
TP304L
485 Min
170 Min
35 Min
TP316
515 Min
205 Min
35 Min
TP316L
485 Min
170 Min
35 Min
ASTM A312 Equivalent Grades
ASTM Grade
UNS Number
Werkstoff No.
TP304
S30400
1.4301
TP304L
S30403
1.4306 / 1.4307
TP316
S31600
1.4401
TP316L
S31603
1.4404
TP321
S32100
1.4541
TP310S
S31008
1.4845
ASTM A312 Pipe Size Chart
Nominal Pipe Size (NPS)
Outside Diameter (OD)
Wall Thickness
Standard Length
1/2"
21.3 mm
SCH 5S to SCH 160
6 m / Random Length
3/4"
26.7 mm
SCH 5S to SCH 160
6 m / Random Length
1"
33.4 mm
SCH 5S to SCH 160
6 m / Random Length
2"
60.3 mm
SCH 5S to SCH 160
6 m / Random Length
4"
114.3 mm
SCH 5S to SCH 160
6 m / Random Length
6"
168.3 mm
SCH 5S to SCH 160
6 m / Random Length
8"
219.1 mm
SCH 5S to SCH 160
6 m / Random Length
10"
273.0 mm
SCH 5S to SCH 160
6 m / Random Length
12"
323.9 mm
SCH 5S to SCH 160
6 m / Random Length
24"
610.0 mm
SCH 5S to SCH 160
6 m / Random Length
ASTM A312 Pipe Schedule Chart
Pipe Schedule
Typical Wall Thickness
Common Applications
SCH 5S
1.65 – 3.40 mm
Low-pressure process piping
SCH 10S
2.11 – 4.19 mm
Food, pharmaceutical & chemical industries
SCH 20
2.87 – 5.54 mm
General industrial applications
SCH 40S
2.77 – 8.56 mm
Process piping & pressure service
SCH 60
3.91 – 10.31 mm
Medium-pressure piping systems
SCH 80S
3.73 – 15.09 mm
High-pressure industrial piping
SCH 100
4.78 – 17.48 mm
Heavy-duty pressure applications
SCH 120
5.54 – 21.44 mm
Power plants & refineries
SCH 160
7.47 – 25.40 mm
Very high-pressure service
XXS
Extra Heavy
Critical pressure piping systems
ASTM A312 Applications
ASTM A312 stainless steel seamless, welded, and heavily cold-worked pipes are
designed for high-temperature and corrosive service. Their excellent corrosion
resistance, durability, and mechanical strength make them suitable for a wide
range of industrial applications.
Industry
Typical Applications
Oil & Gas
Process piping, offshore platforms, gathering systems, and transmission pipelines.
Petrochemical
Chemical processing plants, refineries, storage terminals, and transfer lines.
Chemical Processing
Corrosion-resistant piping for acids, chemicals, and industrial process equipment.
Power Generation
Steam lines, condensate systems, cooling water piping, and power plant equipment.
Food & Beverage
Hygienic processing systems, dairy plants, breweries, and food manufacturing.
Pharmaceutical
Clean process piping, sterile production lines, and pharmaceutical equipment.
Water Treatment
Desalination plants, filtration systems, and water distribution pipelines.
Marine & Offshore
Seawater piping, shipbuilding, offshore platforms, and marine processing systems.
Frequently Asked Questions
ASTM A312 is the standard specification for seamless, welded and heavily cold-worked austenitic stainless steel pipes used in corrosive and high-temperature applications.
Common grades include TP304, TP304L, TP316, TP316L, TP321, TP347 and TP310S stainless steel pipes.
ASTM A312 pipes are widely used in oil and gas, petrochemical, power generation, pharmaceutical, food processing and water treatment industries.
TP316 contains molybdenum, which provides better corrosion resistance than TP304, especially in chloride-containing environments.