Double Tube Core Barrel for Rock Sampling... How does it rotate?

[T2ioTD]

How does a double tube core barrel work for geotechnical rock sampling? Do both tubes rotate in the same direction, or in opposite direction?

 

[fattdad]

there's a water swivel at the top of the inner barrel. As soon as the core enters the core barrel, the core barrel stops rotating and the water swivel rotates against the outer barrel.

f-d

ípapß gordo ainÆt no madre flaca!

 

[BigH]

Its best to use a triple tube