| 摘要 |
Very small metal particles produced in the dielectric liquid of a spark erosion apparatus are removed by passing the liquid downwards through a tall narrow bed of loosely packed sand in a closed housing. The upstream pump and bed dimensions are such that the downward flow exceeds 2 metres per minute through the bed interstices, which facilitates trapping the particles within the bed though they are much smaller than the sand grain. Two beds may operate in series and are backwashed in turn. …<IMAGE>… |
