A drill collar is an essential tool used in oil and gas rigs for drilling operations. It has many functions, including providing weight on the drill bit for efficient drilling and stability during operation.
The drill collar is manufactured from chrome-molybdenum alloy 4140. Furthermore, they are heat-treated and quenched over their entire length, with a Brinell hardness range of 255 to 341 to obtain mechanical properties as specified by API Spec 7-1. Their bore is accurately machined to ensure smooth, balanced rotation. Drill collars are manufactured in a wide range of sizes (ODs) and are available in length ranges 2: 9.15–9.76 m (30–32 ft); and 3: 12.8–13.27 m (42 ft-43 ft).
