Hardbanding has long been acknowledged as an effective means of preventing tool joint wear. During the 1990’s, tungsten carbide-based hardbanding was in widespread use and was determined to be the primary cause of casing wear. However the absence of hardbanding, while slowing casing wear to a small degree, allowed the tool joints to wear at an accelerated rate, lessening the torsional capacity of the drill pipe and putting drilling operations at a serious risk.
The challenge was to discover a balanced, simultaneously effective solution between both casing wear defense and tool joint protection, which is caused by the worsening conditions associated with highly deviated ERD wells. Previous casing friendly alloys reduced casing wear, but produced unacceptable tool joint wear as a consequence. Crack-prone design flaws were also present, as widespread cracking of the alloy material often ensued. This caused catastrophic tool joint failure and in some cases, even the failure of the hardbanding itself, due to tool joint spalling.