IM 2016 November 2016 | Page 56

DRILL CONSUMABLES_proof 27/10/2016 12:34 Page 6

DRILL CONSUMABLES
bits. Varel’s patented conical seal gland
geometrically constrains the seal to better handle
pressure fluctuations and still maintain a
preferred dynamic sealing interference.
“This bit series provides superior performance
in applications including acidic groundwater, high
altitude, or where bit plugging is observed. The
Avenger journal bearing is designed for moderate
to ultra-high pulldown applications where
extended bearing life is required. In addition to
Varel's patented conical seal gland, the journal
design also features Varel’s patented heat shield
to prevent thermal degradation of the seal. A

The new Roller Latch Quick Pump-In Overshot has a new Roller Latch latching system which replaces
the lifting dogs, offering stronger retraction, greater strength and improved durability, and making the
mechanism more resistant to accidental release

Overshot, which will add Boart Longyear’s Roller
Latch latching technology and other
enhancements to an already efficient and

adapter as well as an optional safety quick-pin.
Compatibility with lightweight V-Wall™ drill rods
reduces fatigue on operators and thus further

Wireline core retrieval

dependable product line. Release is expected
during 2017.
The current Quick Pump-In Overshot includes a
pair of lifting dogs with hooked ends that grab a

contributes to safety.
In addition, a new auto-reset spring added to
the landing indicator valve eliminates partial
tripping due to false indications, while a larger

Ever since Boart Longyear introduced the
revolutionary wireline core retrieval system in
1958, the company says its design teams “have

spearhead on the core barrel, allowing sample
retrieval with the wire line cable. A weak spring
allows the operator to easily squeeze the lifting

been refining the system and developing
consumables to support its use in markets across
the globe.” For more than a decade, Boart
Longyear’s Quick Pump-In™ Overshot has
offered maximum productivity in underground or

dogs in order to release the overshot, but
secondary safety devices are required to protect
against accidental release.
A new Roller Latch latching system replaces

fluid bypass porting provides faster wireline
retraction in larger rod strings.
Boart Longyear’s new Roller Latch Quick
Pump-In Overshot also introduces a cable release

patented pressure attenuator mitigates pressure
spikes by restricting access to the seal thereby
prolonging bit life.

pump-in applications. Now, the company says a
next-generation overshot “is about to take
productivity, safety and reliability to new levels.”
Development work and testing continue on the
patent-pending Roller Latch™ Quick Pump-In™

the lifting dogs, offering stronger retraction,
greater strength and improved durability, and
making the mechanism more resistant to
accidental release. Fully compatible with most
core barrel head assemblies, the new overshot
improves driller safety with the easy-loading

mechanism with an optional pump-in release
sleeve that eliminates shear pins. Should the
core barrel become stuck, the mechanism and
sleeve will quickly and reliably release the cable.
Stainless-steel hardware and surface
treatments applied to critical machined
components provide corrosion and wearresistance, contributing to ease of maintenance
and lower operating costs. IM

ISHIGAKI Company, Ltd. • Japan • www.ishigaki.co.jp • Tel. [phone]
ISHIGAKI USA Ltd. • www.ishigakiusa.us • USA • Tel. [phone]
ISHIGAKI Europe GmbH • Germany • www.ishigaki.de • Tel. [phone]
ISHIGAKI Oceania Pty. Ltd. • Australia • www.ishigaki.com.au • Tel. [phone]
Please contact us: [e-mail]

52 International Mining | NOVEMBER 2016