PTA (Plasma Transferred Arc) powder hardbanding was developed to provide cost savings and extend drill pipe life over wire hardbanding especially in highly abrasive formations. PTA powder hardbanding is a metallurgical bonding (welding) process of depositing powdered hardfacing alloys onto magnetic & nonmagnetic drill pipe tool joints, collars and heavy weight drill pipes to protect both casing and drill string assets from abrasive wear. The process involves the application of a constricted high energy plasma arc between a powder alloy and the base material, creating a molten weld pool. This paper presents the operational and cost benefits from the utilization of PTA powder hardbanding. The high energy heat during welding is localized which minimizes the heat affected zone (HAZ), thus retaining mechanical properties in the base metal. PTA powder hardbanding process produces an overlay that has high bonding and overlay with better mechanical wear and corrosion properties than wire hardbanding process. Additional benefits of PTA powder hardbanding over conventional wire hardbanding include: controlled heat inputs with parameter optimization, low dilution of powdered alloy into the base material, uniform weld microstructure & smoother surface and lesser amounts of steel is lost after hardband wear.

PTA powder hardbanding reapplication is dependent on wear and cracking of existing hardband. PTA powder can be reapplied on wire hardbands and vice versa. PTA powder hardband was subjected to casing wear test according to API 7CW standard. Results from the casing wear test proved that the PTA powder hardband is a better casing friendly hardband compared to wire hardbands based on the casing wear percentage, mass lost, contact pressure threshold and tool joint wear in open hole. Field results from an operator in the Delaware Basin, New Mexico show a higher frequency of wire hardbanding reapplication (average of 1 joint every 2 wells) while PTA power hardbanded pipes show lower frequency of reapplication (average of 1 joint every 6 wells).

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