WG and WF Series Double Tube Core Barrels

WG and WF series double tube core barrels are sturdily designed for coring soft to medium  rocks using water, polymer or mud flush. The WF series utilize core bits with face discharge flushing ports to prevent core erosion in soft soils and soft rocks. The WG series utilize core bits with internal discharge flushing and are designed for slightly harder formations.

These core barrels are intended for use in conjunction with DCDMA drill rods and casing.


  • Simple sturdy design
  • Can be used when DCDMA hole sizes N, H, P and S are required.

Technical Data

SpecificationCore Barrel Type



Hole Diameter (mm)75.699.2120.6146.3
Core Diameter (mm)54.776.292.1112.8
Kerf / Crown Thickness (mm)10.311.3513.9516.3
Cutting Area (cm2)21.531.747.768.1
Hole Area (cm2)45.077.3114.3168.1
Cutting Area as % of Hole Area48%41%42%41%
Core Area (cm2)23.545.666.6100.0
Thread Connection in Head*NW



2 7/8 API IF


2 7/8 API IF
Recommended CasingNWHWPWSW
Conversion to triple tube possibleNoYesYesYes

*Cross-over sub required for drill rods not matching the thread connection in core barrel head

Key to Main Parts of WG and WF Core Barrel Assembly

Complete core barrel consists of:

1. Core Barrel Head

2. Inner Tube 1.5m or 3.0m long

3. Outer Tube 1.5m or 3.0m long

4. Ferrule / Inner Tube Extension Piece  (only required for WF series)

5. Core Lifter

6. Core lifter Case (not required for WG series)

Core Bit is not supplied as part of the core barrel assembly, but must be chosen correctly to match the particular application and rock formation. Blank Reaming Shell is supplied with WG Series Core Barrels but TC or Diamond type may be required for some formations. Please refer to our Core Bits page for further details.