General Instruction: We offer a complete line of single & double and triple tube core barrels, which willl provide superior performance and obtain the full recovery of the sample in any application of diamond core drilling. Using a wireline system, core is recovered quickly by retrieving the inner tube directly through the drill string. The rods remin in the hole until the bit needs to be replaced. This has big cost advantages when drilling deep holes for mineral exploration. The core barrel assembly is composed of the inner-tube group and outer-tube group. Advantages: 1.Faster coring at greater depths 2.Good stability due to constant diameter of the drill string 3.excellent hydraulics 4.Good core recovery