No abstract

The work investigates the thermal balance of a low ampere arc. The dependences of the thermal flow in the cathode and anode on the amperage, the diameter of the non-consumable electrode and the length of the arc gap are shown.

No abstract

The influence of the shielding gas composition and the non-consumable electrode construction on the total and effective efficiency of welding was studied. It was found that value total efficiency is at minimum at 25 % helium content and is increasing with the He concentration growth in the gas mixture. The alteration of arc force impact on the welded metal depending on the current rate, shielding gas composition and cathode processing history was demonstrated. It was found that the arcs with a focused cathode spot feature higher value of the integral forced impact on the welded metal, comparing to the arcs with a diffuse cathode spot, regardless the shielding gas composition.

It was demonstrated that applying the flux paste on the back side of the welded joint during welding low-alloyed steels provides control over the sizes of the root and its defect-free formation. It was found that the back bead width is vital to unsupported root formation of thin-walled articles for the considered welding modes.