Universal Engineering Works manufacture Wireline Triple Tube Core Barrel which is similar to a Wireline Double Tube Core Barrel except a third split half stainless steel tube is inserted inside inner tube. It is advantageous to use a Triple Tube Core Barrel in soft, clay, coal, boulder type formations were a less core recovery is being achieved by a normal double tube core barrel.
The third tube i.e. split tube is ejected out with the help of a piston (either hydrualically or by water pressure). Once the split tube has been ejected out the upper half of the split tube is lifted thus exposing the undisturbed core.
To convert the existing double tube core barrel to triple tube core barrel following parts are required to be changed: