| 摘要 |
<p>The concrete part is cast in a mold (1) which has to be vibrated when the material is inserted in order to increase its density. A sealing element (3) in the shape of a ring is attached to the lower area of the mold (1), either made of a ferromagnetic material or provided with magnetic elements. The elements can be several short magnetic strips (4), a few bundles of steel wool (5), steel balls (6), or a metal clamping ring (7). An independent claim is given for the use of the specific sealing element.</p> |
