Which of the following is true about the R suffix in E7018-R?

• A. It designates that the electrode meets the requirements of absorbed moisture testing.
• B. It denotes a higher hydrogen content rating.
• C. It indicates suitability for AC welding only.
• D. It signifies the electrode can be used without baking.

Answer: (A)

The R suffix signals compliance with absorbed moisture testing for the electrode. Low-hydrogen electrodes can absorb moisture from the coating, which raises hydrogen in the weld metal and can lead to cracking. The R designation shows the electrode has been tested for absorbed moisture levels and meets the specified limits, giving you assurance about its moisture performance. The hydrogen content in the weld is controlled by the H designation (if present), not by R, and the suffix doesn’t imply AC-only use or that baking isn’t needed. You still follow the manufacturer’s storage and baking instructions to manage moisture and hydrogen in the weld.