ASTM A333 Pipe Specifications

ASTM A333 Pipe shall be made by the seamless or welding process with the addition of no filler metal in the welding operation.

ASTM A333 Frequently used name: killed carbon steel

ASTM A333 Pipe

ASTM A333 Pipe shall be made by the seamless or welding process with the addition of no filler metal in the welding operation.

This specification covers nominal (average) wall seamless and welded carbon and alloy steel pipe intended for use at low temperatures. Several grades of ferritic steel are included. Some product sizes may not be available under this specification because heavier wall thicknesses have an adverse affect on low-temperature impact properties.

Material & Manufacture

ASTM A333 Pipe shall be made by the seamless or welding process with the addition of no filler metal in the welding operation.

Heat Treatment Requirements

  • All seamless and welded pipe shall be treated to control their microstructure by the following methods:
  • Normalizing per A 333/A 333M-05 section; section or section
  • Quenched and Tempered per A 333/A 333M – 05 section
  • Double Normalized and Tempered per A 333/A 333M – 05 section

Chemical Requirements

 Data Composition, %
Element Grade 1 Grade 3 Grade 6
Carbon, max 0.30 0.19 0.30
Manganese 0.40 – 1.06 0.31 – 0.64 0.29 – 1.06
Phosphorous, max 0.025 0.025 0.025
Sulfur, max 0.025 0.025 0.025
Silicon 0.18 -0.37 0.10 min
Nickel 3.18 – 3.82

For each reduction of 0.01% carbon below 0.30%, an increase of 0.05% manganese above 1.06% would be permitted to a maximum of 1.35% manganese.
When Grade 6 is ordered under this specification, supplying an alloy grade that specifically requires the addition of any element other than those listed for the ordered grade is not permitted. However, the addition of elements required for the deoxidation of the steel is permitted.

Tensile Requirements

The material shall conform to the requirements as proscribed:

Grade 1 Grade 3 Grade 6
psi MPa psi MPa psi MPa
Tensile Strength, min 55,000 380 65,000 450 60,000 415
Yield Strength, min 30,000 205 35,000 240 35,000 240
Longitudinal Transverse Longitudinal Transverse Longitudinal Transverse
Elongation in 2 in. or 50 mm, (or 4D), min, %:
Basic minimum elongation for walls 5/16 in. [8 mm] and over in thickness, strip tests, and for all small sizes tested in full section 35 35 30 20 30 16.5
When the standard round 2-in. or 50-mm gage length or proportionally smaller size test specimen with the gage length equal to 4D (4 times the diameter) is used 28 20 22 14 22 12
For strip tests, a deduction for each 1/32in. [0.8 mm] decrease in wall thickness below 5/16 in. [8 mm] from the basic minimum elongation of the following percentage 1.75 1.25 1.50 1.00 1.50 1.00
Elongation in 2 in. or 50 mm, min, %:

Impact Requirements

For Grades 1, 3 and 6, the notched-bar impact properties of each set of three impact specimens, including specimens for the welded joint in welded pipe with wall thicknesses of 0.120 in. [3 mm] and larger, shall not be less than the values prescribed:

Size of Specimen, min Minimum Average Notched Bar Impact Value of Each Set of Three Specimens Minimum Notched Bar Impact Value of One Specimen Only of a Set Impact Temperature
ft-lbf J ft-lbf J Grade Min Impact
Test Temp
10 by 10 13 18 10 14 F C
10 by 7.5 10 14 8 11 1 -50 -45
10 by 6.67 9 12 7 9 3 -150 -100
10 by 5 7 9 5 7 6 -50 -45
10 by 3.33 5 7 3 4
10 by 2.5 4 5 3 4

Mechanical Testing

Transverse or Longitudinal Tension Test and Flattening Test, Hardness Test, or Bend Test
For material heat treated in a batch-type furnace, tests shall be made on 5% of the pipe from each treated lot. For small lots, at least one pipe shall be tested.
For material heat treated by the continuous process, tests shall be made on a sufficient number of pipe to constitute 5% of the lot, but in no case less than 2 pipe.
Hydrostatic Test
Impact Test
One notched bar impact test, consisting of breaking three specimens shall be made from each heat represtented in a heat-treatment load on specimens taken from the finished pipe.

Order Information

Orders for material under this specification should include the following, as required, to describe the desired material adequately:

Quantity Feet, centimeters, or number of lengths
Name of material Seamless or Welded Pipe
Grade Grade 1, Grade 3, or Grade 6
Size NPS or Outside Diameter and Schedule Number of Average Wall Thickness
Length Specific or Random
End Finish
Optional Requirements
Heat Analysis Requirement
Stress Relieving
Repair by Welding
Other Temperatures for Impact Test
Hydrostatic Test or Nondestructive Electric Test
Test Report Required
Specification Designation and
Special Requirements or Exceptions to this Specification

Referenced Documents

  • A370 Test Methods and Definitions for Mechanical Testing of Steel Products
  • A671 Specification for Electric-Fusion-Welded Steel Pipe for Atmospheric and Lower Temperatures
  • A999/A999M Specification for General Requirements for Alloy and Stainless Steel Pipe
  • E23 Test Methods for Notched Bar Impact Testing of Metallic Materials
Related products
The NORSOK stan