Published on Jan 19, 2016
A portable jackhammer being used to break up a roadsurface in roadworks. The pneumatic hose can be seen leading to the compressor on the back of the truck. The operator is using his body weight to increase the effectiveness of the device.
A pneumatic drill or jackhammer is a portable percussive-drill; operated by compressed air and used to drill rock, break up pavement, etc. It works in the manner of a hammer and chisel, by jabbing with its bit, not by rotating it. A drill, driven by compressed air, which rotates its cutting bit is called an air-drill or, more familiarly, a windy-drill.
A hydraulic jackhammer (on a much larger scale than the portable ones) may be fitted to mechanical excavators and is widely used on roadwork, quarrying and general demolition or constructional groundwork. In mining, it is possible to use this against a vertical wall as the machine can be jacked off the opposite wall of the gallery or some comparable device. For reasons of safety, pneumatic tools are likely to be used underground on a coal mine.
Hydraulic breakers will usually use a hydraulic motor to drive a sealed pneumatic hammer system, as a hydraulic hammer would not only develop a poor striking speed but transfer unacceptable shock loads to the pump system.