Efficiency In Welding
Effective efficiency is a ratio of heat output of this component of the heat balance to the thermal equivalent of electrical power arc. Calorimetric experiments showed that the effective efficiency the process of heating products welding arc depends on the conditions of its combustion and is depending on the method of welding: Submerged – 0,80 0,95 consumable electrode coated with quality – 0,70 0.85; in carbon dioxide – 0.58 0.72; in carbon dioxide cored wire – 0.70 0.85; non-consumable electrode in argon – 0.50 0.60; in argon mag – 0.70 0.80. Coefficient of heat decreases with increasing arc length and increases with the deepening of the arc in the weld pool. On efficiency affect and shape of parts in the welding area – the so-called geometric factor. For example, when beading open arc weld in Cutting efficiency values at 5 10% higher than the cladding onto the plane. With the deepening of the arc in the weld pool efficiency increases due to improved heat transfer between the arc and the workpiece, as well as a decrease in heat loss from the spray electrode materials. For most of the open arcs of length 3 6 mm efficiency is 50 65%.
With full immersion arc, where the radiation loss is only possible through the gaps between the surface of the bath and rod electrode, the efficiency estimated at about 75 85%. Heat expended on heating the arc electrode, flux or shielding gas, in many respects depends on the characteristics of the arc, the conditions and welding conditions. For example, for welding consumable electrode submerged heat expended on heating the electrode and flux, then engaged in a heated base metal that to some extent affects the nature of the input heat of the arc in the product. According to the most common scheme, the heat of the arc is directly transmitted through the product is effective arc spot convective plasma flows along the arc column and radiation. Most closely correspond to this scheme, the arc is relatively small capacity for welding with coated electrodes with a small amount of slag in coverage, as well as non-consumable electrode arc burning in argon. When welding electrodes with high-quality coated or submerged much of the heat is introduced into the product through the filler material, slag, or flux, which leads to much more complex distribution of heat flow. Heat released in the arc, most rationally used in automatic welding.Tags: promyshlennoct and equipment