SA516 Grade70 for boilers

Dimensional Specifications Thickness:8mm-360mm Width:1500mm-4000mm Length:5000mm-18000mm

1.What are the chemical composition and mechanical property of SA516 Grade70 for boilers?

2.What are the performance advantages of SA516 Grade 70?

• High strength: The tensile strength is ≥485 MPa, and the yield strength is ≥260 MPa, making it suitable for high-pressure container design.
• Good weldability: Conventional welding methods (such as SMAW and SAW) can be used, but preheating (usually ≥150°C) and post-weld heat treatment (PWHT) need to be strictly controlled.
• Low-temperature toughness: Suitable for low-temperature environments above -30°C (impact test verification is required).
• Economy: It has a lower cost than chromium-molybdenum alloy steels (such as SA387), but its strength is close to that of low-alloy steels.

3.What are the typical applications of SA516 Grade 70?

• Petrochemical industry: High-pressure reactors, hydrogenation equipment casings, large storage tanks.
• Energy industry: Steam drums of power plant boilers, high-pressure pipelines, nuclear power auxiliary equipment.
• Gas storage: High-pressure natural gas (CNG) storage tanks, liquefied petroleum gas (LPG) equipment.
• Heavy industry: Large chemical containers, high-pressure mining equipment.

4.What is the difference between SA516 Grade70 and SA285 Grade C?

SA516 Grade 70 and SA285 Grade C are both carbon steel materials used in pressure vessel manufacturing, but they have several differences in chemical composition, mechanical properties, and Welding and Processing:

Chemical Composition

• SA516 Grade 70: The carbon content is in the range of 0.27% – 0.31%, the silicon content is between 0.13% and 0.45%, the manganese content is from 0.79% to 1.30%, and the molybdenum content is less than 0.08%.
• SA285 Grade C: It has a lower carbon content compared to SA516 Grade 70, usually around 0.20% maximum. The silicon content is typically 0.15% – 0.30%, and the manganese content is about 0.60% – 0.90%. It generally does not contain molybdenum.

Mechanical Properties

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  Strength:

• • SA516 Grade 70: It has a minimum yield strength of 260 MPa and a tensile strength in the range of 485 – 620 MPa, which is relatively high and can withstand greater pressure and bending stress.
  • SA285 Grade C: The yield strength is lower than that of SA516 Grade 70, generally around 185 – 205 MPa, and the tensile strength is in the range of 380 – 515 MPa.
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  Toughness and Ductility:

  • SA516 Grade 70: It has good toughness and ductility, with an elongation of more than 21%. It also has excellent low – temperature toughness and can withstand low – temperature environments below – 45°C without brittle fracture. At – 20°C, the impact energy absorption value is 26 J.
  • SA285 Grade C: Its toughness and ductility are relatively lower than those of SA516 Grade 70. It has poor low – temperature toughness and may not meet the impact toughness requirements at low temperatures.

Welding and Processing

• SA516 Grade 70: It has good weldability and can be welded by arc welding and submerged arc welding. It also has good machinability and formability and can be processed into various shapes of pressure vessels through forging, rolling, and stamping.
• SA285 Grade C: Its weldability is acceptable, but compared with SA516 Grade 70, its welding process requirements may be relatively lower. It also has good machinability and formability, but its overall processing performance is slightly inferior to that of SA516 Grade 70.

5.What is SA 516 GR 70 equivalent grade?

Equivalent Specifications and Standards of ASTM A516 Grade 70 / ASME SA 516 Grade 70 Plate :