ASTM A515 and ASTM A516 are both ASTM specifications that cover carbon-silicon steel plates primarily used for pressure vessel applications in moderate and lower temperature service. Here's a comparison between the two:
Scope:
ASTM A515: This specification covers carbon-silicon steel plates primarily for intermediate- and higher-temperature service in welded boilers and other pressure vessels.
ASTM A516: This specification covers carbon steel plates intended primarily for service in welded pressure vessels where improved notch toughness is important.
Grade Range:
ASTM A515: Grades 60, 65, and 70.
ASTM A516: Grades 55, 60, 65, and 70.
Tensile Strength and Yield Strength:
ASTM A515: Tensile strength ranges from 415 to 550 MPa (60 to 80 ksi) and yield strength ranges from 220 to 260 MPa (32 to 38 ksi), depending on grade and thickness.
ASTM A516: Tensile strength ranges from 380 to 620 MPa (55 to 90 ksi) and yield strength ranges from 205 to 415 MPa (30 to 60 ksi), depending on grade and thickness.
Notch Toughness:
ASTM A515: Notch toughness is not a specified requirement.
ASTM A516: This specification requires notch toughness testing for all grades to ensure suitability for pressure vessel applications.
Application:
ASTM A515: Generally used for intermediate- and higher-temperature service in welded boilers and other pressure vessels.
ASTM A516: Preferred for service in welded pressure vessels where improved notch toughness is important, particularly at low temperatures.
Normalized vs. Not Normalized:
ASTM A515: Typically normalized.
ASTM A516: Can be either normalized or produced as rolled.
In summary, while both ASTM A515 and ASTM A516 cover carbon-silicon steel plates for pressure vessel applications, ASTM A516 is preferred when improved notch toughness is necessary, especially at lower temperatures, whereas ASTM A515 is more commonly used for intermediate- and higher-temperature service. Additionally, A516 undergoes notch toughness testing for all grades, whereas A515 does not have specific notch toughness requirements.
