| 摘要 |
<p>A yield support prop for a mine includes a first metal tube extending from the mine floor having a first portion having a first outside diameter and a second portion having a second outside diameter. The prop includes a second metal tube that is disposed about the first portion and extends toward the mine roof, when the second tube receives a load from the mine roof, the second portion deforms the second tube and expands the second tube creating resistance against the load from the mine roof. A method for supporting a mine roof. A method for building a yieldable mine prop.</p> |
