导向钻进非开挖铺管施工扩回钻头的设计改进

针对导向钻进非开挖铺设地下管线施工中回扩钻头存在的口径大、包泥堵钻、进尺缓慢、切削齿不耐磨等问题,对钻头结构进行了研究,并从导向钻头、出水口、刮刀、切削齿等四个方面对钻头进行了改进。改进后的回扩孔钻头既有利于切入地层,具有导向和稳定作用,又具有切削阻力低、强度高、耐磨性好的优点,极大的提高了钻进效率。经多项工程检查,扩孔钻头平均单孔耐磨翼片磨损量为1.2～1.75mm,平均〈0.5mm/km。

Design and Improvement of Back Reamer in Directional Drilling Non-excavation Pipe Laying Construction

In allusion to issues of large diameter, bit bailing plugging, rather slow penetration rate and poor wearing resistant cutting teeth in directional drilling non-excavation pipe laying construction, analyzed reamer configuration and to improve the reamer from 4 aspects of pilot bit, bit nozzle, bit wing and cutting tooth. The improved back reamer is in favor of rock cutting, taken effects on drilling guiding and stabilizing, low cutting resistance, high strength, and good wear resistance, thus have improved drilling efficiency greatly. After examination through multiple practices, the wear extent of reamer wear resistant wing is 1.2-1.75mm per single borehole, average 〈 0.5mm/km.