Definition - What does Core Barrel mean?
Core barrels are used to bring up rock samples from the drilling operation. The single tube core barrel is the least expensive and most sturdy one with a head section, core recovery tube, a reamer shell, and cutting bit.
The standard and most preferred is the double tube core barrel in which the outer barrel rotates with the cutting bit while the inner barrel retains the core sample and is either fixed or swivels on bearings.
The core barrel acts as storage for holding the rock or soil core.
Trenchlesspedia explains Core Barrel
Core barrels are used to bring up rock samples from the drilling operation. Core samples are very important for sampling and conducting soil investigation in order to select appropriate boring methods for laying pipelines.
The starter barrel is used to first begin drilling a test borehole. Sometimes single tube core barrels are also used as starter barrels for beginning the core operation. Once it reaches a sufficient depth, the crew replaces the starter barrel with a regular bit and core barrel to extend the hole to the desired depth. The core is then removed and a casing with stabilizers is inserted.
In addition to the drill, a diamond bit, reamer, and drill rods of appropriate length are necessary. A core breaker, core shovel, and core puller are also part of the drilling equipment apparatus.
Trenchless methods such as horizontal directional drilling (HDD), horizontal auger boring (HAB), microtunneling, and pipe jacking use different types of drill bits and cutters to bore through soil or rock.