Question

identify the r in the aws classification for mild steel electrodes.

hydrogen level in ml/100 g
welding position
minimum tensile strength in ksi
indicates impact requirements
electrode
type of coating and current
indicates requirements of absorbed moisture test

e7018-1 h4r

Explanation:

Identify the AWS electrode classification components

Using the AWS Electrode Classification knowledge point
In the AWS classification for mild steel electrodes (such as \(E7018-1\ H4R\)):

• E: Electrode
• 70: Minimum tensile strength in KSI
• 1 (after 70): Welding position
• 8: Type of coating and current
• -1: Indicates impact requirements
• H4: Hydrogen level in ml/100 g
• R: Indicates requirements of absorbed moisture test (moisture-resistant)

Answer:

• Hydrogen level in ml/100 g
• Welding position
• Minimum tensile strength in KSI
• Indicates impact requirements
• Electrode
• Type of coating and current
• Indicates requirements of absorbed moisture test (Correct answer)