2023/07/17
Developing a wear-resistant coating for drilling components
Industries TEKAD, Centre de métallurgie du Québec (CMQ), MBI Global (VersaDrill Canada), Forage André Roy (2022-2023).
Objectives
To develop a coating characterized by its physical and mechanical properties to prevent seal bushing abrasion in drilling operations.
Background
Seal bushings are used in mining exploration to prevent water from penetrating the drilling head. Inserted between the rotating mandrel (1026 steel) and the gasket (urethane), these 6.5-inch diameter parts undergo a rotation of 1,000 RPM for 14 to 16 hours a day. Friction generated in drilling operations causes a great deal of abrasion, despite the 0.002”, 60 HRC chromium layer applied to the bushings by electroplating. After six to eight months of use, the contact area retracts the seal bushing, the chromium coating is completely worn away and the steel is chiselled off, despite the chromium protection. Water begins to penetrate the drilling rod, causing several components to break at a cost that can easily reach $4,000 to $8,000.
The challenge
Seal bushings can be replaced according to current practices, but replacements can take upwards of two to three hours of work, while the cost of the operation can rise quickly to $1,200. Thus, our hypothesis seeks to replace chromium with a material that has shown its wear resistance under extreme operating conditions. To resolve this challenge and to reconcile material properties with the seal bushing’s mechanical requirements (resistance, durability), TEKAD Industries Inc., along with the Centre de métallurgie du Québec (CMQ), MBI Global (VersaDrill Canada), and Forage André Roy Inc., used their expertise to test materials that form chromium micro-carbides during the additive manufacturing process (laser cladding). For this, the focus was set on martensitic stainless steel with high carbon content. The project was funded by the Natural Sciences and Engineering Research Council of Canada (NSERC), the National Research Council of Canada (NRC), and Groupe MISA.