Regulation of the welding current magnetic field during electric arc welding of pipes

ABSTRACT

Mathematical models of magnetic field induction at welding plates and pipes are obtained. The influence of the product shape on induction is established by experiment-calculated way. Magnetic blast during pipe welding increases by more than 10 times due to the concentration of magnetic field lines in a ferromagnetic pipe with high magnetic permeability, the increase in induction by π (3.14) times, the electromagnetic force, acting on an arc and magnetic pressure. A method of one-sided high-speed welding of pipes is developed. In such a case, by passing a current opposite to the welding current inside a ferromagnetic pipe, the magnetic blast is prevented, the process stability is enhanced, upward electromagnetic force and magnetic pressure are created that keep the liquid metal from flowing out of the bath. It ensures the formation of quality seams on a flux cushion and an increase in the impact strength of welded joints by 2–2.5 times.

KEYWORDS:

• Magnetic blast
• process stability
• induction
• electromagnetic force
• magnetic
• pressure
• one-sided high-speed welding
• impact strength