ASTM A778
Basic Info
ASTM A778 covers welded, unannealed austenitic stainless steel tubing intended for general corrosive service and heat-exchanger applications. This standard includes various grades and sizes of welded tubes used in industrial applications where corrosion resistance and durability are essential. It ensures the quality and reliability of stainless steel tubes for corrosive environments.
Characteristics
Welded, Unannealed Austenitic Stainless Steel Tubular Products: Includes various types of welded stainless steel tubes and pipes.
Diverse Applications: Used in a wide range of applications including architectural, structural, and industrial uses.
Mechanical Properties: Provides good mechanical properties suitable for structural applications.
Available in Various Sizes and Shapes: Offered in a variety of sizes, shapes, and finishes to meet different requirements.
ASTM A778 Data Sheet
Steel Grade
Dimensions and Tolerances
Equivalent Grades
Chemical Composition
Mechanical Properties
Fabrication and Welding
Steel Grade
304
304L
316
316L
Dimensions and Tolerances
Round Tube
Width: 6.35 – 101.6 mm
Thickness: 0.5 – 4.0 mm
Tolerances: OD and wall thickness: ±10% or ±0.38mm, whichever is greater
Square Tube
Width: 12.7 × 12.7 mm – 101.6 × 101.6 mm
Thickness: 0.5 – 4.0 mm
Tolerances: Width and thickness: ±10% or ±0.38mm, whichever is greater
Rectangular Tube
Width: 10.0 × 20.0 mm – 50.8 × 101.6 mm
Thickness: 0.5 – 4.0 mm
Tolerances: Width and thickness: ±10% or ±0.38mm, whichever is greater
Equivalent Grades
Germany
DIN 1.4301
Japan
JIS SUS304
China
GB 06Cr19Ni10
Chemical Composition
Carbon (C)
Composition: 0.03% max
Manganese (Mn)
Composition: 2.00% max
Phosphorus (P)
Composition: 0.045% max
Sulfur (S)
Composition: 0.030% max
Silicon (Si)
Composition: 1.00% max
Chromium (Cr)
Composition: 16.0 – 18.0%
Nickel (Ni)
Composition: 10.0 – 14.0%
Molybdenum (Mo)
Composition: –
Nitrogen (N)
Composition: –
Mechanical Properties
304
Tensile Strength (MPa): 515 min
Yield Strength (MPa): 205 min
Elongation (%): 35 min
Hardness (Brinell): 201 max
Impact Strength (J): Not specified
304L
Tensile Strength (MPa): 485 min
Yield Strength (MPa): 170 min
Elongation (%): 35 min
Hardness (Brinell): 201 max
Impact Strength (J): Not specified
316
Tensile Strength (MPa): 515 min
Yield Strength (MPa): 205 min
Elongation (%): 35 min
Hardness (Brinell): 217 max
Impact Strength (J): Not specified
316L
Tensile Strength (MPa): 485 min
Yield Strength (MPa): 170 min
Elongation (%): 35 min
Hardness (Brinell): 217 max
Impact Strength (J): Not specified
Fabrication and Welding
Forming
Stainless steel tubing shall be formed by any means that will not substantially impair the strength of the material.
Heat Treatment
Heat treatment is not required except when specified by the purchaser. If required, it shall be specified by the purchaser.
Welding Process
Welding shall be performed by automatic or manual processes using suitable equipment and procedures.
Weld Preparation
Weld preparation shall be in accordance with good commercial practice, ensuring clean and sound surfaces.
Weld Joint Configuration
Butt joints, lap joints, and other joints shall be made with suitable filler metal and welding techniques.
Welding Filler Metals
Filler metals shall be selected based on compatibility with the base metal and the intended service environment.
Welding Technique
Welding shall be carried out using appropriate techniques to ensure complete fusion and penetration of the weld joint.
Post-Weld Treatment
Post-weld treatment, if required, shall be specified by the purchaser and performed in accordance with the specified requirements.
Inspection and Testing
Welds shall be inspected visually and may be subjected to non-destructive testing methods such as radiographic testing.
Repair of Defects
Defective welds shall be repaired by removing the defects and rewelding in accordance with the standard.
Cleaning and Finishing
Finished welds shall be cleaned and finished to remove any contaminants and achieve the desired surface quality.
Preserving Perfection: The Corrosion-Defying Strength of ASTM A778 Stainless Steel Tubing
Customers seeking reliable materials for their projects are drawn to the exceptional corrosion resistance offered by ASTM A778 stainless steel tubing. In environments where exposure to moisture, chemicals, or harsh weather conditions is a concern, this tubing excels, maintaining its integrity and structural strength over time. Whether used in industrial settings, outdoor applications, or corrosive environments such as marine or chemical processing facilities, ASTM A778 materials provide long-lasting performance and durability. With their resistance to rust, pitting, and staining, these materials offer peace of mind, reducing the need for frequent maintenance and replacement. This outstanding corrosion resistance ensures that structures and components built with ASTM A778 stainless steel tubing maintain their quality and appearance, even in challenging conditions, making them a preferred choice for a wide range of applications.
