New Line of Rotary Drill Heads
Boart Longyear recently released its
new XRH family of rotary heads, comprising
12 base models with various
motor configurations, designed for multipurpose
rotary drilling applications
including jet grouting and reverse circulation.
Featuring patent-pending
electronic valve control technology, the
XRH rotary heads can run two or three
motors and seamlessly switch from
series to parallel operation, eliminating
low-torque startups after making and
breaking joints and manual shifting of
gears. The company states the XRH
rotary heads are extremely powerful,
capable of delivering up to 27,000 Nm
(19,915 ft-lb) of torque or a maximum
rotation speed of 188 rpm, and engineered
to safely handle up to 20,000
kg (44,090 lb) of pullback force. The
heads feature hollow spindles with an
inner diameter of 120 mm, which is
claimed to be the largest in its class
and well-suited for passing large jet
grouting rods, RC drilling or doublehead
drilling where a drifter passes a
large inner string through the XRH
rotary head. The XRH heads also use
high-strength axial bearings designed to
handle the increased stress experienced
by drilling with higher power and
speed. An auto oiler supplies constant
lubrication to bearings independent of
rotary head rotation, extending maintenance
intervals and eliminating the
need for daily maintenance. Premium
bearings, precision ground gears and
synthetic seals are also used to provide
longer and more reliable head life.
www.boartlongyear.com/xrh
As featured in Womp 2010 Vol 09 - www.womp-int.com
