| 摘要 |
<p>Valves used in lines for liquids containing particles may on occasion be prevented by particles adhering between the head and the seat of the valve from assuming a fully closed position. This is prevented by making the valve head (4) capable of turning or rotating in respect of the seat (8), as a result of which obstructing particles can, by turning of the valve head, be cut off, crushed or by other means rendered harmless so that the valve can be fully closed.</p> |
