The construction of water wells is a crucial aspect in the development and utilisation of water resources. For contractors and project managers looking for an efficient water well drilling solution, crawler water well drilling rigs are the ideal choice due to its unrivalled manoeuvrability and stability. Its ability to adapt to a variety of complex terrain conditions ensures that drilling is carried out efficiently. Next, we’ll break down the 7 key steps in the crawler water well drilling process to give you a complete overview of the drilling process.
I.Site Survey and Preparation
Site survey and preparation is the first part of the drilling work, which lays a solid foundation for the subsequent drilling operation. In this step, first is to choose a suitable construction area. Professional technicians will use advanced geological investigation means, such as geological radar, drilling sampling, etc., to carry out detailed investigation of the geological structure of the construction area, the main purpose of which is to accurately determine the location and distribution of aquifers. The aquifer is the key to the water output of the water well, and only accurate positioning can ensure the water quantity and quality of the water well.
After determining the construction area, the area needs to be cleaned and levelled. Remove all kinds of debris in the area to avoid interference with the operation of the drilling rig and the drilling process caused by these debris. In addition, in order to ensure the safety of construction personnel and equipment, it is also necessary to mark the safety zone at the construction site. The division of the safety zone should be reasonably planned according to the operating range of the drilling rig, the possible dangerous situations in the drilling process and other factors. Obvious safety warning signs, such as warning signs and cordons, are set up to prevent unrelated personnel from entering the operation area and avoid accidents.
II.Choose Suitable Drilling Rig Equipment
Choosing suitable drilling rig equipment is one of the key factors for drilling work. In the selection process, it is necessary to comprehensively consider many factors.
Firstly, the drilling depth, different projects have different requirements for drilling depth, and there are obvious differences in the power and performance of drilling rigs required for shallow water wells and deep water wells.
Secondly, geological conditions are an important basis for selecting drilling equipment. Different geological layers, such as soft soil, hard rock, mixed layer, etc., have different requirements for the type of drill bit and drilling method of the drilling rig. For example, in soft soil stratum, the drilling rig needs to have high drilling speed and good chip removal ability; while in hard rock stratum, the drilling rig needs to have strong ability to break rock. Project budget is also one of the factors to be considered when choosing drilling rig equipment. The prices of different models and configurations of crawler water well drilling rigs vary greatly.
Crawler water well drilling rigs come in a variety of types and models to suit different construction needs. If you are newer or don’t know how to choose the right model of crawler water well drilling rig, please tell us your specific needs such as drilling depth, drilling hole diameter, geological conditions, equipped mud pump or air compressor, your budget and other requirements, our sales manager will provide you with professional advice and equipment models.
III Rig Setup and Calibration
Once the rig equipment has been transported to the construction site, it needs to be accurately setup and calibrated.
First, move the crawler drilling rig slowly to the centre of the drilling point. Once at the drilling point, a hydraulic stabiliser is used to enhance the balance of the drill. The hydraulic stabilisers reduce vibration and tilting during drilling by adjusting the expansion and contraction of the hydraulic cylinders to keep the rig’s undercarriage level.
Next, the calibration of the drilling tower angle is performed. For vertical wells, the angle of the drilling tower is usually required to be between 0° and 15°.
During the setup and calibration process, it is also necessary to check the various components of the equipment, such as the tightness of the tracks, the oil level and pressure of the hydraulic system, the operation of the drilling system, etc., to ensure that the equipment is in good operating condition and fully prepared for the subsequent drilling work.
IV.Choose The Right Drill Bit
Drill bit is a key component in the drilling process that is in direct contact with the formation, and whether its selection is appropriate or not directly affects the drilling efficiency and drilling quality.
According to different geological conditions, it is necessary to choose different types of drill bits.
In soft ground, scraper bits or auger bits are common choices. Scraper bits have sharp blades, which can cut soft soil quickly, and the drilling speed is fast; auger bits discharge the cuttings out of the hole through the spiral blades, which is suitable for soft soil formations with high water content.
For hard rock formations, the tricone bit with tungsten carbide teeth is the best choice. The tungsten carbide teeth are extremely hard and wear-resistant and can effectively break up hard rock. During the drilling process, the three-cone bit breaks the rock into small pieces through the rotation and extrusion of the teeth, and then carries the rock chips out of the hole through the drilling fluid.
In mixed layer formations, the presence of both soft soil and hard rock requires the use of a hybrid PDC bit. This kind of bit combines the advantages of scraper bit and three-cone bit, which can adapt to different hardness formations and improve drilling efficiency.
V.Core Drilling And Rock Chip Removal
Core drilling is an important part of the drilling process to obtain formation information and expand the borehole. The rotary drive system is activated to make the drill bit rotate at high speed driven by the drilling column, and at the same time, the column is pushed forward to push the drill bit deeper into the stratum.
As the drill bit rotates, the rock is broken into cores and chips. In order to remove the rock chips in time and keep the borehole open, bentonite slurry or compressed air is injected. Bentonite slurry, as a drilling fluid, has a good ability to suspend and carry rock chips, which can flush the rock chips out of the borehole and at the same time form a layer of mud cake on the borehole wall to stabilise the borehole wall.
During core drilling, torque and drilling speed need to be closely monitored, and these parameters can reflect the changes in the formation. When encountering hard rock layers, the torque will increase and the drilling speed will decrease, at which time the drilling parameters need to be adjusted, such as increasing the drilling pressure and decreasing the rotational speed, in order to adapt to the changes in the formation.
VI.Casing and Cementing
Casing and cementing is a critical step in the drilling process to ensure the stability of the well wall and the long-term use of the well. After core drilling to the designed depth, casing needs to be lowered into the well. Casing is a kind of steel pipe whose function is to support the well wall and prevent it from collapsing, and at the same time to isolate different strata and avoid mutual interference between aquifers.
The selection of casing needs to be based on the drilling depth, formation conditions and the purpose of the water well. The diameter, wall thickness and material of the casing have strict requirements to ensure that it can withstand underground pressure and corrosion. In the process of lowering casing, it is necessary to use tools such as casing pliers to connect the casing one by one to ensure a firm connection and avoid leakage.
After the completion of casing, cementing operation is carried out. Cementing is to inject cement slurry into the annular space between the casing and the well wall, and when the slurry solidifies, it forms a solid cement ring to fix the casing in the well and seal the formation at the same time. The formula of the cement slurry needs to be adjusted according to the formation conditions to ensure that it has good fluidity and solidification strength. During the cementing process, the injection speed and pressure of the cement slurry need to be controlled to ensure that the slurry can be uniformly distributed in the annulus to avoid voids and trenching.
VII.Well Development and Yield Test
During the pumping test, data such as pumping time, pumping volume and water level change need to be recorded, and the capacity and stability of the well can be assessed by analysing these data. Based on the results of the pumping test, the reasonable extraction volume and extraction method of the water well can be determined, providing a basis for the subsequent use of water resources. At the same time, the water wells are regularly maintained and serviced to ensure their long-term stable operation.
In summary, there are 7 key steps in the drilling procedure of crawler water well drilling rig. Each step has its own unique technical requirements and operation points, and requires professional technicians and advanced equipment to ensure the drilling work is completed efficiently, safely and with high quality.
UNIQUE crawler drilling rigs, by virtue of their excellent performance and advanced technology, show strong advantages in each step, and provide a reliable solution for water well drilling projects. Whether in complex terrain conditions or in different geological formations,crawler water well drilling rigs are up to the task and have become an important tool in the field of water resources development. If you are looking for water well drilling rig, please feel free to contact us or get a professional quote.
