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A two-strip electrodes surfacing with controlled transfer of electrode metal is proposed for applying an anti-corrosion layer to the surface of the base metal with a variable angle to the horizon. To prevent the formation of defects in the formation of the deposited layer, it is proposed to adjust the parameters of the surfacing mode in places where the angle of inclination of the surface changes.

Gas-slag-forming systems of flux-cored wires for plasma building-up welding surveyed. Application of substances at overlaying welding boron triphtoride is considered, to provide the improvement of formation of the deposited bead, reduces vaporization. Systems of gas-slag-forming substances which are gating out boron triphtoride are proposed excreting boron triphtoride are investigated at overlaying welding.

The data on the exothermic mixture amount in the electrodes coating influence on their heating and melting are given. Experimental methods found that exothermic reactions in the stage of heating and melting take place at the electrode coating contained more than 35% of the exothermic mixture. It is proved that when there is 58% of the iron scale in the electrodes coating as compared to electrodes containing the same amount of iron powder, the electrode melting rate is increased by 18 -20%, the coating melting mass speed -31 -34% and the electrode melting coefficient -11 -14%. It is proved that the exothermic mixture adding (up to 53,4%) into the electrodes coating leads to effective efficiency heating increasing: basic metal (ηb.m.) from 0,715 to 0,815 and an electrode (ηe) from 0,28 to 0,415. The obtained results can be used in the welding electrodes performance improving development.Statement of the problem. The method of manual arc welding performance increasing is discussing. The aim of researchto determine the exothermic mixture percentage and the electrodes coating thickness influence on the melting process intensification.Currently manual arc welding (surfacing) with coated electrodes is one of the widely used processes. In the industrialized countries, the work performed using manual arc welding amount is 20 -25% of the total, it is 60 -70% in Ukraine [1 -3]. Especially high rate observed in the construction industry, where it can exceed 80 -85% [1]. According to 2014 year statistics data the arc welding with coated electrodes volume in 10...15 years will be 40 -50%.For welding and surfacing a wide range of electrodes is used. However, their productivity is quite low -2,7 kg/h, surfacing and melting rate do not exceed respectively, 8,5 -10,0 g/h•A and 13 -15 m/h. This obliges to pay serious attention to the manual arc welding improvement, which primarily relates to the welding electrodesone of the main factors determining the efficiency and welding technology [3].The welding processes productivity increasing and the search for new raw materials types for their manufacture is one of the main tasks facing the welding and surfacing materials developers. One of the primary ways to increase manual arc welding (surfacing) productivity is the iron powder adding into the electrodes coating. When the iron powder content in the electrodes coating within the values 15 -25% it is welding-technological properties improving without significantly changing the deposition rate. The highest performance is achieved when the electrode coating content of iron powder is 60 -70% with increasing the electrode coating thickness at the same time. However, the «high-performance»