Water

Application of PVC Casing Pipe in Groundwater Drilling:

In the drilling and well completion process for groundwater extraction, PVC casing pipe plays a key role in borehole stabilization, formation isolation, and screen installation. Compared with traditional steel pipes, it offers unique advantages in groundwater drilling.

Borehole stabilization during drilling: When loose formations (such as sand or gravel) or weak mudstone are encountered, the borehole is prone to collapse. Running PVC casing helps stabilize the borehole, prevents collapse and bit burial, and ensures smooth drilling progress. Its lightweight nature reduces the lifting load on the derrick, making it especially suitable for small drilling rigs or operations in remote areas.

Core role in well completion: After drilling is completed, PVC casing serves as the permanent well lining. Slotted or bridge-slot screens can be fabricated directly on the pipe, allowing groundwater to flow into the well while retaining formation sand. The material is corrosion-resistant and non-scaling, so the slots will not become clogged by rust, ensuring long-term flow capacity.

Applicable depth and precautions: PVC casing is generally used in shallow to medium-depth wells (depth ≤ 300 m). Appropriate wall thickness and ring stiffness should be selected based on aquifer pressure. Connections are typically made with solvent cement or rubber ring seals to prevent leakage or separation at the joints. Special attention should be paid: do not lift or lower the pipe abruptly; also, the weight of the pump must never be borne by the PVC casing. Instead, a dedicated support device should transfer the pump load to the ground or to steel pipe sections.

In summary, in the practice of drilling for groundwater, proper selection of PVC casing can significantly reduce the risk of borehole collapse, simplify construction procedures, and extend well life, making it an economical and reliable well completion solution.