Abstract
The digging action of arcs and behavior of molten pool during submerged arc welding have been analized by X-ray fluoroscopic observation.Under the condition of normal bead, molten pool is stable and some molten layer of metal is formed beneath the electrode. On the other hand, under the condition of undercut or humping bead, exposed solid surface is observed beneath the electrode.In two electrode tandem welding with respect to high speed welding, there is a optimum ratio of the trailing electrode current (IT) to the leading electrode current (IL). This is owed to that the effective arcpressure of IL acting to the gravity head of molten metal is decreased by increase of the arc pressure of IT. When IT/IL is smaller than the optimum ratio, the effective arc pressure acting to the gravity head of molten metal is given by IL. But when IT/IL is larger, the effective arc pressure is changed to be given only by IT.Undercut bead is formed when these effective arc pressure become larger than total gravity head of molten metal. The effective arc pressure of each electrode become equivalent and lowest at the optimum ratio of IT/IL ≈ 0.7.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
