Trade fairs - Lenze

Stone for the White House
Integrated automation system makes stonecutters easier to use
Pennsylvania Avenue 1600, Washington,
DC, USA, is perhaps one of the most
famous addresses in the world. That’s
where you will find the White House,
residence and official seat of every
President of the USA since the year
1800. Its foundation stone was laid on
13 October 1792. The most important
material used in its construction was
sandstone, although this can no longer
be seen since the building has been
painted white since the 19th century. It
was this colour which later gave the
building its name.
Such a venerable old building does
of course require maintenance. Environmental
influences eat away at the sandstone
and marble, which has also been
covered over. Specialists are employed
to ensure that the superpower’s headquarters
always looks spick and span.
And wherever the stone becomes
crumbly, new pieces must be put in place.
The stonemasons use special machines
for cutting the replacement blocks.
The new stones are then inserted into
the walls, where they need to be an
exact fit. One of the machines used is a
stonecutter manufactured by Auto-
The site of the White House was chosen
by the first President of the USA, George
Washington. The property on
Pennsylvania Avenue now has 132
rooms, 35 bathrooms, eight staircases,
three lifts, a swimming pool, a tennis
court, a bowling alley and a cinema.
mated Stone Machinery Limited from
Bolton in the United Kingdom. This company
produces machinery for processing
limestone, sandstone, granite and marble,
including saws, cross-cutters and
milling machines.
The latest machine to come from
the British company was developed for
the precise milling of textured stone
such as that used for fireplace surrounds
and ledges on buildings. The cutting
tool is made from extremely hard
polycrystalline diamond and includes a
surrounding water cooling system. It cuts
the stone at up to 9,000 revolutions per
minute.
The machine’s entire automation
system is made by Lenze. At its heart is
the ETC controller which controls both
In action
the movements and the processes. The
machine is operated using a Lenze
industrial PC which is integrated into an
operating station. The software for controlling
the milling machine’s movements
runs on this PC, which also provides
two and three-dimensional visualisation
facilities which enable the
machine operator to view a 3D model of
the tool on the screen, and rotate it.
During the milling process the actual
cut made, and the milling head, are displayed
in real time. ECS drives regulate
tough, dynamic MCS servo motors. The
integrated system is easy to operate,
and the machine can be controlled with
great precision.
www.stone-cutting.com
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