A. Abutment - In coal mining, (1) the weight of the rocks above a narrow roadway is transferred to the solid coal along the sides, which act as abutments of the arch of strata spanning the roadway; and (2) the weight of the rocks over a longwall face is transferred to the front abutment, that is, the solid coal ahead of the face and the back abutment, that is, the settled packs behind the face.
This CNC universal cylindrical grinding machine is designed for grinding medium-sized workpieces in individual and serial production. With the various options, such as in-process gauging, balancing system, contact detection and length positioning, the machine can be adapted for other grinding applications at a later date.
The S21 is designed for grinding workpieces in individual, small batch and high volume production. It can be automated and is especially suitable for grinding high-precision workpieces like those required in the aerospace, precision mechanics and hydraulics/pneumatic industries.