ANALYSIS OF PENETRATION IN ROOT PASS WITHOUT COPPER-BOARD OR ROOT IN OPENING POSITION FLAT, VERTICAL AND OVERHEAD
Herlys Hernando Canizarez Torres1; Sadek Crisostomo Absi Alfaro1; Jose luis Lazaro Plata1
1 UNB
doi:10.20906/CPS/COB-2015-2326
Resumo
In this paper presents an analysis of the penetration effect using the method of groove face inclined in root pass welding was realized, without using copper-joint nor root opening, applied to the three critical welding positions: flat, vertical and overhead, considering the same welding parameters for these positions. The analysis was performed using the MIG / MAG process for derivative short circuit, CMT (Cold Metal Transfer), with AWS ER 70S-6 wires (1.2 mm) and STARGOLD shielding gas. The Central Composite Design was used as a tool for better organization of tests and analysis of the results, carried out in flat sheets of 1020 steel with a narrow-gap in U-shape. The results showed that using the wire 1.2 mm is obtained a full penetration, getting a welding cord with good visual appearance and without internal defects. Based on the results obtained, it can perform root-pass welding in pipes, considering the same welding conditions.
Palavras-chave: Full penetration ; Root pass,; Narrow-gap,; CMT; Central Composite Design