Core /Casing Rods

1. Drill Rods (The Drive Line)
Drill rods are the high-torque pipes that connect the drill rig to the core barrel.
Function: They transmit rotational power (torque) and downward pressure (feed) to the diamond bit while acting as a conduit for drilling fluids.
Design: Most modern rods use Wireline Technology, featuring a large internal diameter that allows the inner core barrel to be hoisted through the center.
Threads: They feature precision-tapered, “leak-proof” threads (like the V-Wall or RQ profile) designed to handle extreme tension and high-RPM rotation.
2. Core Casing (The Protective Shell)
Casing is a larger-diameter outer pipe used to line the borehole.
Function: It “cases off” unstable upper layers (like sand, gravel, or soil) to prevent them from collapsing into the hole. It also prevents the loss of drilling fluids into porous formations.
Installation: Casing is usually “drilled in” or “seated” into solid bedrock, providing a stable, protected path for the smaller drill rods to spin inside.
Flush Joint Design: Unlike standard pipe, casing often features Flush-Joint Threads, meaning the outside and inside diameters are perfectly smooth. This allows the casing to slide easily into the hole and prevents the drill rods from snagging on the way down.