news - Plarad

hout stress!
Day of the demonstration:
A bus with hub-centred wheel rims was provided as
the test object. The bus tyres had had an uninterrupted
service life of approx. 46,000 km. The tightening torque
for the wheel nuts was 600 Nm.
The tools provided by Maschinenfabrik Wagner were
one pneumatic and one electrical bolting tool. First, the
breakaway torque of the wheel nuts on the bus was
measured. This torque was > 1000 Nm. It is amazing
how the tightness of wheel nuts develops after running
such a distance. No wonder normal pneumatic bolting
tools have great diffi culty in releasing these nuts.
The engineers at Wagner know the torque developed by
their products, so, fi rst of all, the pneumatic bolting tool
had to show what it was capable of. With a controlled
air pressure of 4.5 bar and with a soft whir, the wheel
nuts came off as if turned by hand. No noise could be
heard and no vibration was felt in the hands and arms
of the fi tter. Tightening the wheel nuts with a torque of
600 Nm was carried out with a controlled air pressure
of 1.9 bar and was even quieter. Wonderful! Peace and
safety at last for both workers and material. Our fi tters
now looked sceptically at the electrical bolting tool. The
level of the rotary force was set on the potentiometer.
A slight anti-clockwise movement with the sound of a
slowly turning drill, and the wheel nuts were loose. We
were amazed. We had never seen wheel nuts unscrewed
so quickly and so easily. And the tightening went just as
smoothly as the loosening. With no exaggeration,
brilliant. That was the solution for us!
We bought one of each bolting tool. In the following
months, individual extensions and accessories were
specially produced for our requirements. Setting values
for a wide range of torques were documented for the
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bolting tools. Today, the handling of these bolting tools
during our bus repairs has been perfected. We loosen
and tighten more and more with high torque values.
The handling and effi ciency of these bolting tools have
enormous advantages in practical occupational safety.
The fl exibility of the electrical bolting tool would have
saved us many headaches over the years in the
loosening and tightening of bolted joints. We are
currently planning to fi t an inverter from 24 V to 220 V in
our breakdown truck so that we can use the electrical
bolting tool for fi tting work on the wheels of our vehicles.
Unfortunately, there is also a drawback. These bolting
tools are very costly to procure. But when the frequency
of use and the personal safety benefi ts for our fi tters
are taken into account, their procurement is absolutely
economical in the long term.” ■
For more information, contact:
Ralf König, Master Automotive Technician
r. koenig@stadtwerke-remscheid.de
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