| 摘要 |
<p>The rotary-disc-type stopcock is gastight, the seal being effected by pressure in the stopcock housing, e.g. of gas, higher than that in the piping. Thus the prod. cannot penetrate into the housing, and a clearance volume is formed. The disc can be of PTFE-cpd., with low friction and high elasticity. Any leak is detected by a pressure drop in the housing, shown on an indicator or setting off a warning signal.</p> |
