General procedures for performing a hot section (turbine and combustion section) inspection. The entire external combustion case should inspect for evidence of hotspots, exhaust leaks, and distortions before the case is opened. Combustion chambers inspection for localized overheating, cracks, or excessive wear. Inspect the combustion chamber outlet ducts and turbine nozzle for cracks and for. Submerged-arc welding (SAW) is an arc welding process. It is especially suited for plate thicknesses between two and 100 millimeters. SAW is typically used in the heavy metal industry. Submerged-arc welding: the technology. Friction Stir Welding (FSW) is considered to be the most significant development in metal joining in recent decades. In this investigation, the quality and corrosion behavior of a submerged. Despite the fact that a submerged arc welding machine is commonly applied in the industry in an automated or mechanic way, semi-automatic submerged welding machines with flux feed equipment are available. Due to the highly automated process welding, setups are mainly to carry out horizontal and groove welds. This is how SAW works. At present, the Narrow Gap Submerged Arc Welding is an advanced welding technology. As the weld is very deep and narrow, the slag is difficult to clean and will have impact on the quality of welding seam. Therefore, a new kind of narrow gap submerged arc welding slag cleaning device is designed to clean the welding slag.

Abstract:

Longitudinal hot tearing, popularly called as end cracking, frequently takes place in the end portions of large steel panels’ butt joints, using one-sided, submerged-arc welding with flux copper backing welding process (FCB welding). The study was to look for the possibility to improve and/or prevent the end cracking issue during FCB welding, center blind-hole drilling technique was used to measure the welding residual stress for five different cases, considering hot tearing mechanism, its influence factors and the relevant reported prevention measures. Unpredictable result was observed subsequently that transverse compressive stress is found on the shallow surface of weld seams, which could give supplementary information to the common assumption for conventional low heat input welding method that cracks initiation is caused by tensile stresses across the welded joints. The study concluded that FCB welding end cracking issue is caused by the comprehensive function of different stresses, and also properly use tack welding practice, suitable elastic run-off plate and relatively low heat input energy which will reduce the end cracking susceptibility for the tested materials.

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