Construction Technology for Directional Drilling Crossing Pebble Layer of Yellow River
The construction technology of direc-tional drilling crossing the pebble layer of the Yellow River in the Boai-Luoyang coalbed methane pipeline project is summarized.For directional drilling crossing the pebble layer,casing can be used to isolate the peb-ble layer,and the casing can be pushed into the rock layer to ensure the stability of the pebble layer during construction.For the long-distance rock layer crossing,dual drilling machines are used to drill guide holes and connect them within the rock layer.The power reamers are used for simultaneous reaming with dual drilling machines to ensure smooth hole walls and smooth pull-back.The mud configuration is optimized,the mud wa-ter loss is reduced,the mud wall protection,lubrica-tion,and affinity with formation drilling cuttings are en-sured,it is ensured that drilling cuttings are wrapped in mud colloids,and the formation of drilling cuttings beds is prevented.Environmentally friendly additives and plugging agents are added to the mud to change the rheological properties of the mud,so that the rheologi-cal parameters of the mud can meet the requirements of preventing mud leakage and effectively carrying drilling cuttings.At different drilling stages,different mud dis-placements and drilling construction techniques are a-dopted to avoid the occurrence of mud running,leak-age,and mud leakage during the drilling process.
directional drillingpebble layercasingreaming with dual drilling machinesmud con-figuration