Surface World December 2019 Surface World December 2019 | Page 58

TESTING & MEASUREMENT
LK Metrology introduces new range
of compact CMMs with the latest
multi-sensor technology
LK Metrology
announces the new,
ALTERAC ceramic-
bridge coordinate
measuring machine
(CMM) range.
Using the latest
metrology software,
multi-sensor
technology and
CMM designs, the
compact systems
are intended for
demanding quality
control applications.
A range of CMMs has
been introduced by British
manufacturer LK Metrology
offering high accuracy and
repeatability in a compact
footprint. Built at the company's
factory near Derby, the new
ALTERAC machines are available in three
sizes - 7.7.5, 10.7.5, and 10.7.7 - their
respective X,Y,Z axis movements being 700 x
650 x 500 mm, 1,000 x 650 x 500 mm and
1,000 x 650 x 650 mm. Typical applications
are likely to be found in the aerospace,
automotive, medical and other industries
with demanding inspection requirements.
ALTERAC is equally at home in an inspection
department or on the shop floor, especially
as pneumatic mounts isolate the CMM well
from nearby sources of low frequency
vibration such as large machinery.
The CMM control may be either stand-alone,
or integrated into the machine base with
a keyboard on an arm at the side, giving
the customer a choice that best suits the
installation site. The latter option also
facilitates relocation of the equipment once
installed. The inclusion of Renishaw encoders
with 0.05 µm resolution optical scales for
high volumetric accuracy not only leads to
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bridge section, and is finely
tuned to maximise stiffness,
reduce vibration and provide
smoothness of axis motion,
all of which are fundamental
to delivering high accuracy
measurements. Such is LK's
confidence in its design methods
that it offers an unparalleled
10-year guarantee covering
dimensional stability.
All guideways use LK-designed,
low maintenance, pre-loaded
air bearings of wrap-around
design offering 3.5 times higher
stiffness than standard air
bearings. They run with a
reduced air film thickness for
low energy consumption and
give repeatable measurement
results, even at fast axis speeds.
Friction drives provide smooth
motion and exact positioning
at continuously varying speeds,
as well as zero backlash,
overload protection and
low maintenance costs.
outstanding metrology but also provides
immunity to the ingress of contaminants.
Measurements taken with a touch-trigger
probe at a series of points, ideal for
acquiring information on dimensional
accuracy, is increasingly being augmented
by continuous-contact probing (analogue
scanning) and laser scanning to allow high
speed collection of data on complex freeform
surfaces. ALTERAC measuring machines are
able to deploy all three types of sensor.
Such flexible data acquisition boosts
measurement throughput to avoid
bottlenecks in the metrology department,
provides a comprehensive awareness of
component conformance, and meets today's
manufacturers' requirement for a CMM that
underpins concurrent engineering practices
to speed time to market for new products.
The CMM structure has been optimised using
computer aided solid modelling and finite
element analysis, particularly within the
DECEMBER 2019
Careful selection of materials
in the machine construction
includes, as with all LK CMMs, the use of
ceramic for the moving bridge and spindle.
It is more than three times stiffer than
aluminium yet only one-third heavier
by volume, resulting in higher machine
acceleration and speed. Ceramic does not
stress-relieve like aluminium, leading to
better long-term dimensional stability.
The thermal expansion coefficient of
ceramic, which is similar to that of granite
but four times lower than aluminium's,
makes the structure highly resilient to thermal
movement. Moreover, ceramic is three times
harder than aluminium, so is more resistant
to abrasive wear and indentation.
ALTERAC is available with LK’s powerful
CAMIO8 DMIS-based, multi-sensor
software enabling programming and
measurement based on 3D CAD data
and comprehensive reporting.
Visit: www.LKmetrology.com
read online: www.surfaceworld.com