difference between a E8018G and a E8018G-H4

admin

What is the diffence between a  a E8018G and a E8018G-H4 welding rod?Is it just the Hydogen content? some are H4R what does the R stnad for?
Reply:i aint sure, i believe some of the designation h4r means it can be out of the can 8 hours instead of 4 hours...?
Reply:H4 indicates the diffusible hydrogen limit for the rod, if it is properly handled, and indicates that less than 4ml diffusible hydrogen will be contributed to the weld metal per 100g deposited. The standard (if not labeled otherwise) is 16, I think, for 7018, 8018, etc.The R indicates moisture resistant covering. This indicates that the rod can meet the hydrogen requirements under a particular set of conditions (temperature, humidity) for longer than a standard rod. This is still only about 9 hours, but is longer than standard rod. If the rod is unsealed and not in an oven for longer than specified, it may not be able to meet the low hydrogen limit.
Reply:thank you