近海不下套管井深100 m海砂钻探技术

对于井深100m的海砂地质钻探，不下套管，一径到底，直接在松散无胶结的砂质沉积地层取心钻进，大大降低了劳动强度和提高了生产效率。在黄海某砂矿岩心钻探调查项目中，易产生孔壁坍塌、岩屑返不出孔口、涌砂、卡钻等严重问题。通过解决施工中遇到的问题，总结了井深100m的海洋砂矿钻探工艺技术，以及孔内事故的防治措施，为后续工作提供了技术参考。

100 m Depth Well Drilling without Casing in Offshore Sand

For 100 meter depth geological drilling in offshore sand, directly coring in non-cementing loose sandy sediments formation without casing greatly reduces labor intensity and improves working efficiency. Hole wall collapsing, difficult cuttings upward, sand gushing and drill pipe sticking are often encountered in the core drilling investigation in offshore sand of Yellow Sea. The paper summed up the drilling process technology for the well of 100 meter depth in offshore sand and the prevention measures for downhole accident.