Protecting Threaded Surfaces on Tubing Strings Used in the Oil and Gas Industry

The paper reviews an research to design technology to apply protective coatings to threaded surfaces on tubing strings used in the oil & gas industry. This tubing is used to operationalize oil & gas wells, transport gases and fluids, and perform fixing and tripping jobs.

Tubing strings are operated in corrosive environments, especially in fields with high contents of sulfur and other chemical compounds, and are subjected to abrasive wear, fluctuating pressures and alternating loads during in/out spinning. These factors contribute to a higher accident rate during field tripping operations (~80% accidents involving borehole equipment). The key cause of these accidents is the destruction of threaded joints.

An efficient way to address the problem is to use pipes with new thermal spraying protective coatings. Accordingly, a series of coatings have been developed and operationally tested, thus opening up the next work stage, i.e. full-scale tests in the field.