Sample Encapsulation Technology

Rock and soil core samples are typically extracted using a rotary drill and a hollow coring bit. A core sample encapsulation technology was developed which uses a cylindrical sample sleeve made from heat shrink tubing material. The sleeve is placed into a coring bit which has film heaters and temperature sensors mounted on the inside wall. The device can be activated while the drill bit is still in the drill hole, thus preserving sample integrity before the core is even extracted. The cores would be further preserved by the addition of a heat shrink cap. A hermetic seal is created by heat welding the cap to the sleeve with a thin heating wire. Furthermore, with heaters and thermocouples inside a coring tool there is the opportunity to do significant in-situ science like the measurement of thermal diffusivity of rocks and soil. The feasibility of this technology was demonstrated through a trade study, thermal analysis and the fabrication of prototype hardware.