Reducing the Risk of Kickback Injury
WARNING
To reduce the risk of kickback injury,
avoid cutting with the upper quadrant of
the wheel where possible. Be especially
cautious for a pinching or binding of the
wheel in this area, which can cause
severe reactive forces in a rotational
kickback motion.
Avoid wedge action. The severed part
must not bind the abrasive wheel.
TS 410, TS 420
Be alert to potential movement of the
workpiece or anything else that could
cause the cut to close and pinch the
wheel. In order to reduce the risk of
pinching, support the workpiece in such
a way that the cut remains open during
the cutting process and when the cut is
finished (see illustration). Never make a
cut that results in a binding of the wheel.
If you cannot properly support the
workpiece, do not use a cutting-off
machine to make the cut; select another
tool or cutting technique that is not
subject to kickback.
Where there is a possibility of a pinch,
you can leave an uncut part that
prevents the kerf from closing and
pinching the wheel, which can later be
broken manually. If you are making a
complete cut, make sure that the final,
separating cut is made at the top of the
workpiece with the bottom of the wheel.
In this way, if there is any residual
pinching, it will be at the bottom of the
wheel, where it may result in pull-away,
but not in kickback. Be alert for pull-
away.
Objects to be cut must therefore be
properly supported and must be secured
against rolling away, slipping or
vibrations.
Support an exposed pipe in a trench so
that it is stable and capable of bearing
weight. If the ends of the pipe are firmly
in the ground, the ground may act as a
support where the pipe emerges into the
open. Additional support will be needed
closer to the cut, however, to prevent
sagging (see illustration). Be alert for
pipe that is under stress that may cause
it to shift when cut; pipe in the ground
may be under stress because of uneven
surfaces.
Make sure any section of pipe to be
removed is also properly supported and
will not shift. After the first cut, you may
need to move the supports or add
additional support for the second cut so
that both sides of that cut are fully
supported, including the section to be
removed. That section can also be
supported by means of a strap from
above, e.g., suspended from a backhoe.
It must be evenly supported and
properly tensioned, however, so that the
section remains in its position and does
not tend to go up or down as a whole or
on one side when separated.
Always pay attention in
subgrade/subsurface work areas –
supporting material can crumble or slide
away.
English
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