Materials & Standards

What does ASTM A320 L7 mean for low-temperature bolting?

ASTM A320 L7 is a widely specified alloy-steel bolting grade associated with low-temperature service.

2026-08-076 min
01

The grade name alone is not enough

Compliance should be reviewed across diameter, manufacturing method, heat treatment, mechanical values, impact testing, finish and certification scope.

02

Charpy and project requirements

Impact-test temperature and acceptance criteria may be separately defined by the project specification or purchase documents. The MTC should be checked against the requested test temperature and specimen information.

03

Procurement checklist

The following points should be clarified during enquiry and order review.

  • Standard and grade
  • Diameter, length and thread form
  • Heat-treatment requirement
  • Charpy test temperature and acceptance
  • Surface treatment
  • EN 10204 3.1 and additional records
  • Marking and traceability
This content is for general information. Final product and documentation requirements must be verified against the applicable standard, drawing and project specification.