Sandvik has introduced a multifunctional N surface and underground (NSU) core barrel system; a first of its kind that features interchangeable components and offers standard and pump-in applications in a single system.

The NSU core barrel system features an innovative new design that will not only increase productivity, but also offer a more cost-efficient solution by reducing net working capital and spare parts inventory, as well as safer operations when handling the system.

"Our newly patented iQ-FCV valve provides and maintains a constant alert via sustained high water pressure, assuring the operator that the inner tube assembly has positively latched into the core barrel, eliminating mislatches and ensuring valuable time is not lost," said Sandvik Mining core drilling product line manager Chris Daws.

"For better water efficiency, the iQ Valve has been designed to always retain the volume of water in the drill string even in broken ground or dry holes, which is an important benefit in core drilling."

The overshot attachment to the wireline no longer requires cable eyes or cable splicing, enabling easier maintenance and repair in the field. A newly designed logic tip on the overshot allows for in-hole dry releasing of the inner tube assembly once the water level has been reached, shortening the release time. The pump-in overshot features a ball valve indicator which alerts the operator of positive latching onto the core barrel’s back end.

The NSU core barrel system is user-friendly and designed for safer handling operations. The intelligent overshot is automatically latch-locking and latches can be released without the presence of fingers in potentially high risk areas. A knuckle joint is featured on the overshot, which allows for ease of handling, particularly in the confined space of underground drilling conditions. Load-rated breakaway safety pins also provide a safer way to release the overshot from stuck inner tubes.

"The Sandvik NSU and forthcoming H surface and underground (HSU) core barrel systems share the majority of components used in the core barrel head assembly," Daws added.

"With the interchangeable design for both systems, the NSU core barrel head assembly can easily be converted into a HSU core barrel head assembly and vice versa. This will significantly reduce parts and spare parts inventory. The new core barrel system is designed for both standard and pump-in applications, which means there is no longer a need to keep different coring tools systems on the shelf and reducing the net working capital for the owner."

The HSU core barrel system will be released later in Q2 this year.