| 摘要 |
<p>The device has a rod or tube which protrudes from the wall, so forming a support with which screws may be introduced or clamps fitted. A protection tube is slipped over the rod (in compression) and practically butts on to the wall. An internal protection tube is also provided, coned outwards towards the bottom of the hole in the masonry. A synthetic piece is placed inside this and can expand the tube outwards by a cone/wedge action on turning a screwed rod, carrying a cone at its far end. The synthetic piece is in the form of a coned and helically wound thin element.</p> |
