2022 Jiangsu Jingjiang HDL-200C Drilling and Cementing at the Yangtze River Tunnel, Jingjiang Section

Geological Conditions:

Location (Province): Jiangsu

Location (City): Jingjiang

Drill Rig Model: HDL-200C type top drive drill rig

Drilling Tool Configuration: 168 sets of pipes + 73 drill rods

Construction Technology: Drilling and cementing

Geological Conditions: 0～23 meters sandy soil layer, 23～28 meters gravelly sand layer, 28～36 meters natural soil layer

Construction Angle (°): 90

Pipe diameter (mm): 180

Hole depth (m): 36

Construction Efficiency (min): 150

Pure drilling time (min): 15

Pure disassembly of drill tools time (min): 15

On-site use of frozen pipes

Construction Method:

1. Prepare the site, dig a concrete pit, mix the cement (water + admixture) in the pit, and lay down steel plates to create a platform; locate the drilling point;

2. Position the drill rig, install the drilling tools, align with the drilling point, measure the first rod of drilling tools left and right using a level tool, and adjust it to a vertical state; lower the mast to the platform and secure it;

3. Start the screw pump, clockwise + feed in, uniform speed, hole mouth has reverse cementing, and pay attention to controlling the pump pressure within 3-5 kg/cm²; if the drilling is slightly slow, immediately increase the shock drill to maintain a steady pace;

4. Insert the pipe coupling into the lower gripper, stop the pump, disconnect the coupling, and install the drilling tools;

5. Install each drilling tool in sequence, uniform speed, and drill to the required depth (prepare the next pipe segment beforehand); remove the drill rod as quickly as possible and push the drill rig back 1 meter;

6. Insert the next pipe section (60 seconds to position)