Tubing Coating

Sucker-rod wear on production tubing has been an industry issue for decades, resulting in the need for costly workovers. Grit and sand exacerbate the problem, along with corrosives such as hydrogen sulfate, methane, and carbon dioxide. Diamond Scientific was asked by United Casing to develop a product to extend the life of the tubing at wear points. A 5-year research and development project resulted in the ACR-T16 coating. While the primary concern is abrasion of the tubing, a variety of tests were performed by independent laboratories to ensure the corrosion stability of the coating. Autoclave tests for corrosion in various atmospheres, pressures, and temperature variations were conducted, resulting in excellent adhesion and no coating loss or blisters in aqueous, hydrocarbon, or liquid phases. Wear-resistance tests determined that the coating demonstrated an increased resistance of more than an 1,100% improvement over J55 steel. Currently, 150,000 ft of production tubing has been coated at wear points in multiple wells. The coated tubing has been in service for 21 months without need for any workover. Before running the coated tubing, these wells required a workover every 6 months.

A Taber abrasion machine, used to test Diamond Scientific’s ACR-T16 tubing coating.