| 摘要 |
<p>Filters for petroleum, oil etc. have a cut-off mechanism as well as a casing that effects automatic drainage. The cut-off mechanism can be closed by a screw fixture so that the contents of the external filter casing can be removed by a bottom valve positioned in the casing. The inner filter casing has an opening at its bottom which is open during filtering to facilitate flow between the inner and the outer filter casing.</p> |
