Analysis of the standard process of drilling construction: quality control points at each stage

Analysis of the standard process of drilling construction: quality control points at each stage

The birth of a high-quality water well relies on a set of strict standard construction processes. From preparation to final delivery, each stage has its core quality control points. As a user, understanding these key points can help you effectively participate and supervise to ensure the quality of the final well.

1. Preparation stage: the “foundation” of planning and positioning

This sets the right direction for the entire project.

Point 1: On-site survey and precise positioning: The construction party should confirm the well location with you. It must avoid septic tanks, garbage dumps, underground pipelines and other pollution sources and obstacles, and consider the convenience of future water collection and maintenance. This is source control to prevent water pollution and construction risks.

Point 2: On-site inspection of materials and equipment: Check whether the on-site drilling rig model, drill pipe bit, well pipe (material, diameter), filter material (gravel), etc. are consistent with the contract, and check their appearance quality.

2. Drilling stage: “Exploration” of depth and stratigraphic records

This is the process of exploring underground conditions and finding aquifers.

Point 1: Control of drilling verticality: Ensure that the drilling rig is installed smoothly and the drilling angle is correct to prevent excessive deflection of the wellbore, which will affect subsequent pipe running and water intake.

Point 2: Observation of rock cuttings and stratigraphic records: The construction party should observe and record changes in drilled rock cuttings (soil, sand, gravel) at any time to determine the stratigraphic structure and possible aquifer location. This is an important basis for determining the depth of the final hole.

Key node control: When drilling to a predetermined depth or encountering signs of good water content, the final hole depth must be measured and confirmed with the construction party, and a joint decision must be made based on cuttings samples whether to continue deepening.

3. Pipe laying and well cementing stage: building the “life body” of the water well

This is the core link that determines the lifespan and water quality of the water well, and no step can be wrong.

Point 1: Well pipe quality and connection: Before running the pipe, confirm on site that the well pipe (usually PVC or stainless steel) is not damaged or deformed, and the position and length of the water filter pipe (perforated part) meet the requirements. The lowering process should be smooth and vertical, and the connection should be tight and firm.

Point 2: Filter material filling (the core quality point): The annular space between the well pipe and the hole wall must be filled with clean, uniform gravel (filter material), and it is absolutely prohibited to backfill with excavated sand. The high-quality filter material layer can effectively filter sand, increase water output and protect well pipes. It should be monitored whether the filling process is continuous, even and substantial.

Point 3: Pipe mouth sealing: Above the filter material layer, high-quality clay or special materials should be used for tight sealing to prevent dirty surface water from seeping along the pipe wall and contaminating groundwater.

4. Well cleaning and sampling stage: Awakening and verifying “production capacity”

New wells need to be thoroughly "cleaned" and "tested" before they are ready for use.

Point 1: Fully clean the well: Use an air compressor or a large pump to clean the well vigorously and continuously until the water changes from turbid to continuously clear and sand-free. This removes mud and fine particles that invade the aquifer during drilling and clears waterways.

Point 2: Strict trial pumping: Install a water pump to conduct trial pumping for several consecutive hours (usually 4-8 hours). You need to focus on:

Stable water output: Whether it meets the contract or can meet your water needs.

Dynamic water level changes: whether the water level drops within a reasonable range when pumping water, and how quickly the water level recovers after stopping the pump. This reflects the water richness and recharge capacity of the aquifer.

Intuitive judgment of water quality: water should be clear, odorless, and without obvious impurities.

5. Completion and delivery stage: establishment of files and clarity of responsibilities

A good ending means a good beginning.

Point 1: Data transfer: The construction party should provide a "Well Completion Report", which at least includes: final well depth, static water level, downpipe depth, filter material filling depth, construction date, etc. This is the "ID card" of the well and is crucial for future maintenance.

Point 2: Site cleanup and final acceptance: The construction party should restore the site to leveling. After you confirm that the water quantity and quality are satisfactory and receive the information, you will complete the final acceptance.

In summary, the quality control of drilling construction is an interlocking chain: the preparation stage determines the direction, the drilling stage determines the situation, the pipe laying stage establishes a solid foundation, the washing and testing stage verifies the performance, and the delivery stage clarifies responsibilities. As a user, your supervision should focus on the three core nodes of joint confirmation of the final hole depth, personal witnessing of filter material filling, and personal verification of test pumping results. With this focused involvement, you can work with the builder to create a good well that will last.