ASTM A333 Standard Specification for Seamless and Welded Pipe

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Update time : 2025-01-07 09:20:46

   ASTM A333 Seamless and Welded Steel Pipe for Low-Temperature Service and Other Applications with Required Notch Toughness

        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.

  Size Range:

  1/4” Nominal to 24”O.D.

  Wall Thickness – Schedule 10 through XXH

  Unscheduled heavy wall pipe thicknesses available up to 4 inches.

  ASTM A333 Low Temperature Steel Pipe Heat Treatment

  All seamless and welded pipes manufactured to ASTM A333, other than Grades 8 and 11, shall be heat treated to control their microstructure in accordance with one of the following methods:

  Normalize by heating to a uniform temperature of not less than 1500 °F [815 °C] and cool in air or in the cooling chamber of an atmosphere controlled furnace. Or normalize as above-mentioned, and, at the discretion of the manufacturer, reheat to a suitable tempering temperature.

  For the seamless process only, reheat and control hot working and the temperature of the hot-finishing operation to a finishing temperature range from 1550 to 1750 °F [845 to 945 °C] and cool in air or in a controlled atmosphere furnace from an initial temperature of not less than 1550 °F [845 °C]. Or treat as above-mentioned, and, at the discretion of the manufacturer, reheat to a suitable tempering temperature.

  Seamless pipe of Grades 1, 6, and 10 may be heat treated by heating to a uniform temperature of not less than 1500 °F [815 °C], followed by quenching in liquid and reheating to a suitable tempering temperature.

  ASTM A333 Grade 8 pipe shall be heat treated by the manufacturer by either of the following methods: quenched + tempered; double normalized + tempered. When required, Grade 11 shall be annealed and then normalized in the range of 1400 to 1600 °F [760 to 870 °C].
Strike temperature condition

Crade The lowest temperature for strike test
℉ ℃
ASTM A333 Grade 1 -50 -45
ASTM A333 Grade 6 -50 -45


Mechanical requiremnts of ASTM A333 alloy pipe

Grade Tensile Strength (MPa) Yield Point (MPa) Elongation (%)
Y X
Grade 1 ≥380 ≥205 ≥35 ≥25
Grade 3 ≥450 ≥240 ≥30 ≥20
Grade 4 ≥415 ≥240 ≥30 ≥16.5
Grade 6 ≥415 ≥240 ≥30 ≥16.5
Grade 7 ≥450 ≥240 ≥30 ≥22
Grade 8 ≥690 ≥515 ≥22  
Grade 9 ≥435 ≥315 ≥28  
Grade 10 ≥550 ≥450 ≥22  
Grade 11 ≥450 ≥240 ≥18  


Chemical Composition (%) of ASTM A333 steel pipe

Grade Chemical Composition (%)
C Si Mn P S Cr Ni Cu Mo V Al
Grade 1 ≤0.30   0.40-1.06 ≤0.025 ≤0.025            
Grade 3 ≤0.19 0.18-0.37 0.31-0.64 ≤0.025 ≤0.025   3.18-3.82        
Grade 4 ≤0.12 0.18-0.37 0.50-1.05 ≤0.025 ≤0.025 0.44-1.01 0.47-0.98 0.40-0.75     0.04-0.30
Grade 6 ≤0.30 ≥0.10 0.29-1.06 ≤0.025 ≤0.025            
Grade 7 ≤0.19 0.13-0.32 ≤0.90 ≤0.025 ≤0.025   2.03-2.57        
Grade 8 ≤0.13 0.13-0.32 ≤0.90 ≤0.025 ≤0.025   8.40-9.60        
Grade 9 ≤0.20   0.40-1.06 ≤0.025 ≤0.025   1.60-2.24 0.75-1.25      
Grade 10 ≤0.20 0.10-0.35 1.15-1.50 ≤0.03 ≤0.015 ≤0.15 ≤0.25 ≤0.015 ≤0.50 ≤0.12 ≤0.06
Grade 11 ≤0.10 ≤0.35 ≤0.6 ≤0.025 ≤0.025 ≤0.50 35.0-37.0   ≤0.50    


Production specification range of low temperature pipe products

No. Order No. Size description
O.D. W.T. Legnth
/mm /mm /m
1   10~127 1~20 6~12.0
42~114.3 3.5~6 6~12.2
42~114.3 6~12 6~12.2
114.3~180 3.8~8 6~12.2
A333 Gr.6 114.3~180 8~22 6~12.2
A333 Gr.6/X42NS 68~180 10~14 6~12.2
  69~254 14~55 6~12.2
  140~340 6~8 6~12.2
  140~368 8~42 6~12.2
  318~720 14~50 4~12.5
2 A333 Gr.6/X52QS 42~114.3 3.5~12 6~12.2
114.3~180 3.8~22 6~12.2
68~254 10~40 6~12.2
140~368 6~40 6~12.2
318~720 14~40 4~12.5
140~368 6~25 6~12.2
318~720 14~25 4~12.5
3 16MnDG 10~127 1~20 6~12.0
42~114.3 3.5~12 6~12.2
114.3~180 3.8~22 6~12.2
68~254 10~55 6~12.2
140~368 6~42 6~12.2
318~720 14~120 4~12.5


  ASTM A333 Low Temperature Steel Pipe This specification covers wall seamless and welded carbon and alloy steel pipe intended for use at low temperatures. The pipe shall be made by the seamless or welding process with the addition of no filler metal in the welding operation. All seamless and welded pipes shall be treated to control their microstructure. Tensile tests, impact tests, hydrostatic tests, and nondestructive electric tests shall be made in accordance to specified requirements.

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