ASTM A27 Welding Guidelines

ASTM A27 Welding is straight forward task but require knowledge about welding requirements. ASTM A27 is a carbon steel cast material available in different grades.

ASTM 27 is a low- medium carbon steel cast steel used for pump, valves and casings. Welding can be carried out using stick welding, TIG welding, MIG welding and Flux cored arc welding.

ASTM A27 Material Specification

ASTM A27 is the material specification for A27 casting materials. ASTM A 27 is not an ASME material and hence welding P Number is not specified in the ASME Section IX for this grade. Although it is equivalent to P1 G1 materials.

ASTM A27 Material Grades

The ASTM A27 standard covers the chemical composition and mechanical properties required for grades of carbon steel castings:

Grade N-1
Grade N-2

Grade U 60-30
Grade 60-30
Grade 65-35,

Grade 70-36,
Grade 70-36
Grade 70-40.

Each grade has unique characteristics that make it suitable for certain applications such as pumps, valves, gears, supports, shafts, struts and more.

ASTM A27 chemical composition & Mechanical Properties

The chemical compositions and mechanical properties of different ASTM A27 grades are given in the below table.

The minimum tensile strength of ASTM A27 Grade 70-36 & 70-40 is 70 Ksi. The first two-digits A27 grades reflect its minimum tensile strength.

Similarly, the minimum tensile strength of ASTM A27 Grade 60-30 & 65-35 is 60 Ksi.

ASTM A27 grade 65-35 Welding

Welding of ASTM A27 grade 65-35 Welding shall be carried out using E7018 stick welding rod or ER70S-6/ ER70S-2 TIG or MIG welding wire.

Use pure argon gas shielding for TIG welding and Ar+CO2 gas mix (75-25 welding gas) for MIG welding of ASTM A27 material.

Preheat temperature shall be applied when welding thicker material. Use a preheat temperature of 80°C or 175°F for higher thickness (More than 1 inch).

You can calculate the preheat temperature using our free Online Preheat Calculator.

The maximum interpass temperature for ASTM A27 is 600 °F (315 °C). Post weld heat treatment- PWHT (Stress relief-SR) if required shall be carried out at a temperature of 593°C– 649°C or 1,100°F–1,200°F.

ASTM A27 grade 60-30 Welding

Welding of ASTM A27 grade 60-30 Welding shall be carried out using E6018 or E7018 stick welding rod or ER70S-6/ ER70S-2 TIG or MIG welding wire.

Use pure argon gas shielding for TIG welding and Ar+CO2 gas mix (75-25 welding gas) for MIG welding of ASTM A27 material.

Preheat temperature shall be applied when welding thicker material. Use a preheat temperature of 80°C or 175°F for higher thickness (More than 1 inch). You can calculate the preheat temperature using our free Online Preheat Calculator.