Technical Points for Deep Well Drilling to 200 Meters

Technical Points for Deep Well Drilling to 200 Meters

I. Basic Equipment Requirements

1. Drilling Rig: A large-scale professional drilling rig is required, with a lifting capacity of no less than 8 tons and a power rating of at least 55 kW. The rig height should be no less than 9 meters to ensure the use of long drill pipes and safe tripping.

2. Drill Strings: High-strength, thick-walled drill pipes, such as oil drill pipe series, are required. In hard rock formations, diamond drill bits or down-the-hole hammers are necessary. To ensure borehole verticality, centralizers should be installed at intervals.

3. Supporting Equipment: The mud pump displacement must be sufficiently large (recommended at least 120 cubic meters per hour), and mud purification equipment such as vibrating screens should be provided. An inclination meter must be provided to regularly monitor the borehole direction.

II. Core Technological Points

1. Well Structure: A staged drilling approach, from large to small, is typically adopted. First, a large-diameter shallow hole is drilled and a surface casing is installed. Then, a smaller diameter drill bit is used to drill deeper, and finally, a filter pipe is installed in the water-bearing section. 2. Drilling Control

Adjust parameters flexibly according to the formation: use "high drilling speed, low drilling pressure" for soft formations and "high drilling pressure, low drilling speed" for hard formations. Maintain unobstructed mud circulation at all times to carry cuttings and cool the drill bit.

3. Mud Management

Use high-quality low-solids mud for wall protection, and regularly test and adjust its viscosity and density. This is crucial for stabilizing the deep wellbore and preventing collapse.

III. Key Technical Measures

1. Deviation Prevention and Correction

Deviation must be measured at every drilling depth (e.g., 50 meters). Deviation must be corrected promptly, using light pressure drilling or a dedicated deviation correction tool assembly.

2. Leakage Prevention and Possession

When encountering mud leakage in fractured formations, treatment should be graded according to the severity of the leakage: minor leakage can be treated with plugging materials (e.g., sawdust, fiber); severe leakage requires the use of quick-setting cement or casing for isolation.

3. Well Completion Process

After well completion, a thorough mud replacement and well flushing are necessary to remove sediment from the borehole. Before running the casing, the aquifer location must be accurately detected, and the filter pipe must be aligned with the aquifer. Finally, a thorough pumping test should be conducted to verify the water output and quality.

IV. Safety and Quality Reminders

Safety First: All equipment must be securely installed. Regularly inspect critical components such as wire ropes and overhead cranes.

Complete Records: Record detailed data on drilling parameters, formation changes, casing depth, etc., for future reference.

Professional Team: Deep well drilling is complex; it is recommended that it be operated by an experienced professional team.

Deep well drilling is a systematic project. The key to success lies in equipment matching, reasonable parameters, and timely responses. Sufficient preparation and standardized operation are fundamental guarantees for drilling a good well.