| 摘要 |
<p>The present document provides a screening apparatus having a stack of screens (31,36,46) for retaining within a recycled drilling mud fluid, some solids within a particular size range. This fraction of solids is frequently referred to as lost circulation material or bridging material.
Solids above a specified size can be removed with the top screen (31) and rejected, while solids of a smaller size but greater than a second size, can be separated with the second screen (36) and subsequently returned to the drilling fluid mud system, with solids smaller than those removed by the second screen but larger than a third size, may be removed with a third screen (46) and rejected. In other cases it may be desirable to return only the largest size particle fraction separated out at the first screen (31), for return to the drilling fluid where this is used in formations with particularly large pore size.</p> |
