What does the R suffix in E7018-R indicate?

• A. It signifies the electrode has been re-touched after storage.
• B. It designates that the electrode meets the requirements of absorbed moisture testing.
• C. It indicates the coating color is red.
• D. It means the electrode is approved for underwater welding.

Answer: (B)

The R suffix on this electrode designation signals moisture-related testing. Specifically, it indicates the electrode has met the requirements of absorbed moisture testing. Low-hydrogen electrodes can pick up moisture from the coating or environment, and excess moisture can cause hydrogen cracking or brittle welds. By designating the electrode with the R suffix, manufacturers indicate it has been tested to ensure its absorbed moisture level stays within acceptable limits, so it will perform as a low-hydrogen electrode when stored and used correctly.

Other options don’t fit because the suffix isn’t about re-touching after storage, coating color, or underwater welding capabilities.