Core barrel introdution:

Used in loose, broken stratigraphic or coal extraction and protect rock (mine) heart of drilling tools.

Double core tube and tube has outer pipe, rinses through joint between the internal and external tube water flow to the bottom of the hole, protecting cores from rinses washouts. Double core tube has double motion and single movement two kinds. Double motion and core tube is internal and external core tube following bit and drill stem rotation, it in no serious loose or broken strata.

Single movement double core tube internal and external tube has bearing isolation, pipe outer pipe driven only pick up bit rotation, and broken rock tube does not rotate, avoid to core friction, vibration, etc., with mechanical damage, so it in serious loose fractured formations.these, can be well protected cores.

Use double deck core tube take core, bits need to use wall thickness of the alloy drill or diamond bits.

Due to the rock drill contact surface area increased and the lip use double deck core tube than ordinary core tube drilling efficiency to reduce. In the ledge, coal, in order to guarantee rock (mineral) heart take rate, rules must be use double deck core tube coring. More complex double core tube, except to finish single movement, in addition, aluminum, steel tube placed plastic or qualitative buckled half close tube, have a better protection of the core role.

Double core tube card broken cores and seal block within the next port, the core tube by the drill is placed in the core card fault device (fern, card spring, claw reed, etc.) to finish.

Core barrel demension:

N Series Wireline Double Tube Core Barrels:

Wireline double core barrels are primarily used in deep coring. With an overshot device, they eliminate the need to couple and uncouple the rod string each time the core is retrieved. Available sizes in AQ, BQ, RQ, NQ, HQ, and PQ.

T2 Series Double Tube Core Barrels: The T2 Series are thin wall double tube core barrel, used for surface exploration, especially mining  applications. Due to their thin kerf, these core barrels provide rapid penetration. Available in diameters  46, 56, 66, 76, 86, 101mm.

TT Series Core Barrels:

Very thin cutting face allows very rapid rate of penetration through hard formations. They are suitable for underground mining applications.

T6 Series Double Tube Core Barrels:

These are a continuation of the T2 series, but of a sturdier design and available in larger diameters,  76, 86, 101, 116. 131 and 146mm. They are applied in surface mining and geotechnical drilling.