Flexible drilling syatem air lifting drilling rig

Generally, the pile hole using the circulating drilling process of mud wall protection needs to carry out the first positive circulation slag cleaning. First of all, the positive circulation slag cleaning needs a relatively large mud proportion, otherwise the sediment can not float out.
And rotary drilling static slurry wall protection, the process itself is small mud proportion, to use positive circulation slag cleaning, but to artificially increase the proportion of mud, not necessary. Your stratum, the sand layer is so thick, if it is my construction will generally choose polymer chemical mud, the mud proportion is small, the sediment precipitation after the hole is small, the wall protection effect is also better.
Therefore, after the hole is dug by rotary digging, it is not necessary to clear the hole by positive circulation, directly under the steel cage, install the catheter, and carry out the air lift reverse circulation cleaning before perfusion.