Influence of marine corrosion on the roughness of the dry hyperbaric underwater MAG welding joints

Abstract

The maintenance and repairing actions for underwater metallic structures from maritime and offshore field are usually achieved using the gas metal arc welding processes. The welding processes applied should take into consideration different underwater conditions, and experiments should be conducted for different pressures. In the first part of the study, the authors focused on the investigation of the EH 36 shipbuilding steel behaviour subjected to dry hyperbaric metal active gas (MAG) using semi-automatic welding devices. Hereinafter, the authors analyse, by using the electrochemical method, the behaviour of the welded joints to marine corrosion. In the last part of the investigation, the corrosion influence on the roughness of the specimen’s surfaces, depending on the potentiodynamic polarization curves, is approached. The experiments revealed that increasing of pressure conditions leads to an increased corrosion resistance and moreover, to a decrease of the specimen surfaces roughness.

Design of electromagnetic adsorption drainage cover for underwater welding

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