Posted by
Cutter on Wednesday, July 23, 2008 4:00:00 PM
Tool types
A combination spreader-cutter with a built-in, manually operated pump
Detail of a combi-tool's blades.
In operation, the tips of the spreader-cutter's blades are wedged into a seam
or gap — for example, around a vehicle door — and the device engaged. The hydraulic
pump, attached to the tool or as a separate unit, powers a piston that pushes
the blades apart with great force and spreads the seam. Once the seam has been
spread, the now-open blades can be repositioned around the metal. The device
is engaged in reverse and the blades close, cutting through metal. Repeating
this process allows a rescuer to quickly open a gap wide enough to pull free
a trapped victim. The blades can spread or cut with a force of several tons
or kilonewtons with the tips of the blades spreading up to a meter.
This operation can also be performed by dedicated spreading and cutting
tools,
which are designed especially for their own operations and may be required
for some rescues.
[edit] Rams
Rams are used far less than spreader-cutters in auto rescues; nonetheless,
they serve an important purpose. There are many types and sizes, including
single-piston, dual-piston and telescopic rams. Sizes commonly vary from 50.80cm
(20") to 178cm (70") (extended). Rams use more hydraulic fluid during operation
than spreader-cutters, so it is essential that the pump being used have enough
capacity to allow the ram to reach full extension.