Welding E7010/8010 versur E7018
Welding E7010/8010 versur E7018
(OP)
Can someone tell me if there is a specific advantage regarding the use of E7010/E8010 versus E7018 for CS and under what conditions are they preferred over one another. Also, regarding hydrogen underbead cracking (delayed cracking), is there a tensile strength or material thickness where low hydrogen electrodes become a factor in lowering the liklihood for underbead cracking? Thanks.





RE: Welding E7010/8010 versur E7018
The last prefix in the XX has to do with rod covering and slag type from welding. You have various coverings depending on end use - cellulose, low hydrogen iron powder, sodium, potassium, etc.
Click on the link below to obtain information on the various types of coatings for covered electrodes. This handbook is fairly decent on providing covered electrode selection.
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Underbead cracking has more to do with base metal chemical composition and selection of proper preheat requirements to assure adequate diffusivity of hydrogen and to avoid the formation of harmful martensite in the base metal HAZ. My advice is to use low hydrogen, covered electrodes for welding medium to higher strength carbon and low alloy steels with the SMAW process. The low hydrogen covered electrode needs to be specified by the suffix designator H4 or H8 per AWS A5.1.
RE: Welding E7010/8010 versur E7018
RE: Welding E7010/8010 versur E7018
Good question. I would suggest that you calculate the carbon equivalent (or CE) for the base metals that you are interested in joining. It is a good exercise in using the CE equation, as mentioned in the FAQ below.
FAQ330-1077
Typically, medium to higher strength steels will contain alloy elements that must be considered when welding. Using the CE will provide you to determine preheat requirements from published sources. Any steel with a CE that is above 0.45 should be welded with low hydrogen electrodes to avoid delayed cracking.
RE: Welding E7010/8010 versur E7018
RE: Welding E7010/8010 versur E7018
RE: Welding E7010/8010 versur E7018
With respect to cracking (and its avoidance), take a look at ISO TR 17844
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdo/
RE: Welding E7010/8010 versur E7018
RE: Welding E7010/8010 versur E7018
stanweld refers to the main advantage.