| 摘要 |
<p>The compressed air is fed into the space between the flanges through nozzles in the flange of the cover and these nozzles are connected to a pipe on or in that flange or pref. to the annular channel formed by the outer wall of the cover, the top of its flange and an annular piece part fixed across the corner between them. Leakage is prevented as in the ingress of impurities.</p> |
