| 摘要 |
<p>The outer hollow cone is threaded on its inside and carries a wear pad to seal it in its large base. A hollow cylindrical screw nut has an outside thread to match the interior cone thread and also has an interior thread so that it can be screwed onto threaded rods which remain bedded in the cast concrete. When the cylinder is screwed home it pushes a sealing ring to the base of the cone which is shaped to receive it, the sealing ring being of a deformable but incompressible material.</p> |
