Surface Engineering Alternatives for Increase Corrosion Resistance and Wear Performance of Ball Valves for the Oil and Gas Industry
In petroleum production and separation processes frequently the components suffer wear and corrosion due to the contact with the corrosive fluid which could be contain solid particles. In certain dynamics equipment like as ball valves, the deterioration generated causes the operations equipment exit at short times about a month. The main elements of the valves deteriorated are the seats and corks, which are made of 4140 steel. The aim of the present research was evaluating extend the life time of the components using two thermal spray coatings systems: WC-12%Co alloy by HVOF and FeCrB alloy by AWS. The evaluation of wear resistance of these coatings was achieved by means of abrasion wear tests according to ASTM G65-C. The microhardness of the coating was determined by means of Vickers indentation using a load of 300g and the corrosion behavior was evaluated by potentiodynamic polarization tests. The results showed that the best performance in corrosion and abrasion conditions correspond to the HVOF WC-12%Co coating.