Desarrollo de un sistema de escotilla para la determinación de hidrógeno difusible en soldadura submarina

The design and implementation of hatch mechanism aims to optimize the development of welding simulations performed in the Robotic, Welding and Simulation Laboratory. The project is part of the upgrade technologies applied to sciences of the sea, and make it possible to evaluate the influence of welding parameters on SMAW and FCAW processes, especially as regards the content of diffusible hydrogen specimen welding in different depths. Due to the specifications imposed by the gas chromatography standards applied to welding, tests must be carried out at short intervals, which requires a fast process. This research will promote the evaluation of commercial electrodes and promote the development of new consumables.El diseño e implementación del mecanismo de escotilla, tiene como finalidad optimizar el desarrollo de simulaciones de soldadura ejecutadas en el Laboratorio de Robótica, Soldadura y Simulación. El proyecto hace parte de la actualización de tecnologías aplicadas a ciencias del mar, y posibilitará evaluar la influencia de los parámetros de soldadura en los procesos SMAW y FCAW, especialmente en lo que se refiere al contenido de hidrógeno difusible en cuerpos de prueba soldados en diferentes profundidades. Debido a las especificaciones impuestas por las normas de cromatografía de gases aplicadas a la soldadura, las pruebas deben desarrollarse en intervalos cortos, lo cual exige un proceso rápido. Esta investigación fomentará la evaluación de electrodos comerciales y promoverá el desarrollo de nuevos consumibles

Development of a hatch system for the determination of diffusible hydrogen in underwater welding

The design and implementation of hatch mechanism aims to optimize the development of welding simulations performed in the Robotic, Welding and Simulation Laboratory. The project is part of the upgrade technologies applied to sciences of the sea, and make it possible to evaluate the influence of welding parameters on SMAW and FCAW processes, especially as regards the content of diffusible hydrogen specimen welding in different depths. Due to the specifications imposed by the gas chromatography standards applied to welding, tests must be carried out at short intervals, which requires a fast process. This research will promote the evaluation of commercial electrodes and promote the development of new consumables.El diseño e implementación del mecanismo de escotilla, tiene como finalidad optimizar el desarrollo de simulaciones de soldadura ejecutadas en el Laboratorio de Robótica, Soldadura y Simulación. El proyecto hace parte de la actualización de tecnologías aplicadas a ciencias del mar, y posibilitará evaluar la influencia de los parámetros de soldadura en los procesos SMAW y FCAW, especialmente en lo que se refiere al contenido de hidrógeno difusible en cuerpos de prueba soldados en diferentes profundidades. Debido a las especificaciones impuestas por las normas de cromatografía de gases aplicadas a la soldadura, las pruebas deben desarrollarse en intervalos cortos, lo cual exige un proceso rápido. Esta investigación fomentará la evaluación de electrodos comerciales y promoverá el desarrollo de nuevos consumibles

The Effect of Polarity and Hydrostatic Pressure on Operational Characteristics of Rutile Electrode in Underwater Welding

In order to provide a better understanding of the phenomena that define the weld bead penetration and melting rate of consumables in underwater welding, welds were developed with a rutile electrode in air welding conditions and at the simulated depths of 5 and 10 m with the use of a hyperbaric chamber and a gravity feeding system. In this way, voltage and current signals were acquired. Data processing involved the welding voltage, determination of the sum of the anodic and cathodic drops, calculation of the short-circuit factor, and determination of the melting rate. Cross-sectional samples were also taken from the weld bead to assess bead geometry. As a result, the collected data show that the generation of energy in the arc–electrode connection in direct polarity (direct current electrode negative-DCEN) is affected by the hydrostatic pressure, causing a loss of fusion efficiency, a drop of operating voltage, decreased arc length, and increased number of short-circuit events. The combination of these characteristics kept the weld bead geometry unchanged, compared to dry weld conditions. With the positive electrode (direct current electrode positive-DCEP), radial losses were derived from greater arc lengths resulting from increasing hydrostatic pressure, which led to a decrease in weld penetration