ASTM A333 (ASME S/A-333) Pipe grades permit low temperature service. This specification covers nominal (average) walled pipe almost exclusively in seamless. Several grades of ferritic steel are included. Some product sizes may not be available under this specification because heavier wall thicknesses have an adverse effect on low-temperature impact properties. A333 pipe is furnished to nine different grades designated by numbers 1, 3, 4, 6, 7, 8, 9, 10, & 11. Discussed herein are Grades 1 and 6.

Sizes
1/4” Nominal to 24”O.D.
Wall Thickness – Schedule 10 through XXH

Chemical Properties % Unspecified Chemistry Max %

C Mn P S Si Cr Cu Mo Ni Cb V
Grade 1: 0.30 0.40-1.06 0.025 0.025 – – – – – – –
(Note: This is similar chemistry to A53/SA53)
Grade 6: 0.30 0.29-1.06 0.025 0.025 0.10 min 0.30 0.40 0.12 0.40 0.12, max 0.08 max
(Note: This is similar chemistry to A106/SA106)

Mechanical Properties: Grade 1 Grade 6

Tensile Strength, min, psi (MPa) 55,000 (380) 60,000 (415)

Yield Strength, min, psi (MPa) 30,000 (205) 35,000 (240)

CVN Impact (Charpy) Test:

Minimum Impact Test Temperature

Grade 1 -50 (F) -45 (C)

Grade 6 -50 (F) -45 (C)

Heat Treatment:

Grades 1 and 6 shall be heat treated to control their microstructure.