Wireline Double Tube Core Barrels

Wireline core barrels are used when coring to greater depths, mainly because they eliminate the need to couple and uncouple the rod string each time the core is retrieved. An overshot device is dropped on a cable and directly couples onto the inner tube assembly, allowing fast retrieval of the core after each core run. Available in DCDMA sizes B, N, H. and P.


  • Faster coring at greater depths
  • Good stability due to constant diameter of the drill string
  • Excellent hydraulics
  • Good core recovery
Technical Data
SpecificationCore Barrel Type
Hole Diameter (mm)59.975.796.3122.8
Core Diameter (mm)36.447.663.585.0
Kerf / Crown Thickness (mm)11.613.916.218.5
Cutting Area (cm2)18.327.241.161.7
Hole Area (cm2)28.345.072.8118.5
Cutting Area as % of Hole Area64%60%56%52%
Core Area (cm2)10.317.831.756.8
Recommended Drill RodB W/LN W/LH W/LP W/L
Recommended CasingBWNWHWPW
Conversion to triple tube possibleYesYesYesYes
Key to Main Parts of W/L Core Barrel Assembly

Complete core barrel consists of:

1. Core Barrel Head

2. Inner Tube 1.5m or 3.0m

3. Stop Ring

4.Core Lifter

5. Core Lifter Case

6. Locking Coupling

7. Adapter Coupling

8. Landing Ring

9. Outer Tube 1.5m or 3.0m

10. Inner Tube Stabilizer

11. Thread Protector

Core Bit  and Reaming Shell are not supplied as part of the core barrel assembly, but must be chosen correctly to match the particular application and rock formation.  Please refer to our Core Bits page for further details.