ASTM A387/A387M Grade 21L vs ASTM A387/A387M Grade 21
Strong Match — 96.2% match
based on chemical composition and mechanical property overlap.
ASTM A387/A387M Grade 21L (ASTM A387/A387M:2011) and ASTM A387/A387M Grade 21 (ASTM A387/A387M:2011) are both steel grades.
Both fall under the Alloy Steel category.
ASTM A387/A387M Grade 21L is typically used for welded boilers and pressure vessels for elevated temperature service, while ASTM A387/A387M Grade 21 is commonly used for welded boilers and pressure vessels for elevated temperature service.
ASTM A387/A387M Grade 21L is defined under ASTM International, originating from United States, while ASTM A387/A387M Grade 21 is defined under ASTM International, originating from United States.
As per chemical composition, ASTM A387/A387M Grade 21L vs ASTM A387/A387M Grade 21 is a 94.3% match.
As per mechanical properties, the match is 100%.
Combined, this makes them a strong match overall at 96.2%.
Frequently Compared With ASTM A387/A387M Grade 21L:
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property
ASTM A387/A387M Grade 21L
ASTM A387/A387M Grade 21
Tensile Strength
415-585 MPa
415-585 MPa
Yield Strength
>=205 MPa
>=205 MPa
Elongation
>=18%
>=18%
Condition
Class 1 plates, no thickness ranges printed; elongation in 50 mm gauge length
Class 1 plates, no thickness ranges printed; elongation in 50 mm gauge length
Typical Applications
ASTM A387/A387M Grade 21L
Welded boilers and pressure vessels for elevated temperature service
ASTM A387/A387M Grade 21
Welded boilers and pressure vessels for elevated temperature service
Can ASTM A387/A387M Grade 21L Be Substituted With ASTM A387/A387M Grade 21?
ASTM A387/A387M Grade 21L and ASTM A387/A387M Grade 21 overlap closely enough on chemistry and mechanical properties that ASTM A387/A387M Grade 21 is often considered as a substitute for ASTM A387/A387M Grade 21L in many applications. Always confirm the specific property range your application needs before substituting, and check with your supplier's mill certificate.
What is the difference between ASTM A387/A387M Grade 21L and ASTM A387/A387M Grade 21?
Both grades share a similar composition profile; see the specification table above for the exact chemistry and mechanical property values.
Can ASTM A387/A387M Grade 21L be substituted with ASTM A387/A387M Grade 21?
ASTM A387/A387M Grade 21L and ASTM A387/A387M Grade 21 overlap closely enough on chemistry and mechanical properties that ASTM A387/A387M Grade 21 is often considered as a substitute for ASTM A387/A387M Grade 21L in many applications. Always confirm the specific property range your application needs before substituting, and check with your supplier's mill certificate.