Aplicación del código AWS D1.1 en juntas soldadas en T mediante el proceso SMAW para identificar discontinuidades a través del método de líquidos penetrantes e inspección visual.

Abstract

The purpose of the study is to identify discontinuities in T-welded joints using the AWS D1.1 Code and non-destructive testing methods such as visual inspection and liquid penetrant inspection applied to the coated metal arc welding (SMAW) process. For this study, the material selected is ASTM A - 36, a common structural steel in Ecuador for infrastructure works due to its strength and ability to be welded easily. The PROWAR welding machine model MMA - 301 together with E - 6011 electrodes of 1/8” diameter, suitable for welding in all positions; in addition, it guarantees a high penetration in the welding process, which makes it suitable for welding thicker metals. The study was carried out in different phases. First, cleaning and preparation of the plate surfaces, followed by T-joint welding of the specimens using the SMAW process. Subsequently, visual inspection to reveal discontinuities in the weld bead, using the liquid penetrant technique under ASTM E165 and ASME section V standards for inspection. Finally, we compiled the information from the inspections in cards in order to give an acceptance criterion allowing us to approve or reject the specimens. The results revealed several discontinuities in the weld such as: convexities in 7 %, craters in 15 %, slag in 5 %, lack of fusion in 30 %, cracks in 8 %, shape in 3 % and shape in 3 %. 8 %, shape in 3 %, bite in 20 %, pores in 2 % and low weld in 10 %. These discontinuities are evident in the structural integrity of the welded joints. This method provides a complete and reliable evaluation and demonstrates the need to follow regulatory procedures to ensure the durability and safety of metallic structures. The specimens subjected to both visual and liquid penetrant tests did not meet the acceptance criteria established in the AWS D1.1 code, therefore, none of the specimens submitted for inspection were approved.