- Inspection and measurement work of DTH Hammer
First, we must understand the drilling time, drilling depth, service life, pumping water volume, water turbidity, previous well washing conditions, longest pumping time and management and protection of the pumped well. Then carry out the measurement of the motorized well, from the depth of the water surface to the bottom of the well, (that is, the thickness of the groundwater layer), and the height of the water surface to the ground, to check and measure the depth of siltation and silt (silt, bricks, stones, etc.) underground , Concrete block). Find out whether the arrangement of underwater protective wall pipes is misaligned or collapsed, and make relevant records.
Two treatment methods
According to the results of the inspection and measurement, if there is silt in the well, or the original wall pipe collapses, bricks and stones, etc., the dredging work must be carried out in the well, and the fishing bucket is used to salvage all the silt in the well. Clear to the bottom of the well. In the process of dredging, due to the up and down movement of the bucket, the arrangement of the underwater protective wall can also be observed. If everything is normal and there is no siltation and collapse, repairs will be easier.
Three choice of materials
The material for the maintenance and reconstruction of the old motor well is mainly the concrete wall pipe of the organic well. The general specifications are 4m in length, 37cm in outer diameter, 29cm in inner diameter, and 4cm in wall thickness. 8mm; When the arrangement of the original wall protection pipes in the well is misaligned, due to space limitations, steel pipes with an outer diameter of 219mm can be used. In recent years, some U-PVC plastic pipes of the above specifications have been used for wall protection. The filter material adopts gravel with a particle size of 10-20mm.
Four maintenance and reconstruction of pumped wells
In the motorized well drilled with an impact cone in the 1970s, the outer diameter of the wall pipe is 80cm and the inner diameter is 65cm. For maintenance, a concrete wall pipe with an outer diameter of 37cm and a length of 4m or a steel pipe with an outer diameter of 273mm is inserted into the original wall pipe. The underwater part adopts water filter flower tube, and the water part adopts concrete solid pipe or steel pipe solid pipe. According to the calculation of the length from the bottom of the well to the ground, the concrete wall pipe (or steel pipe wall pipe) is purchased. Calculate the volume between the concrete flower tube (or steel pipe flower tube) and the original protective wall pipe, and purchase the filter material, also known as the surrounding stone. These concrete pipes are hoisted with hoisting equipment and welded section by section to the bottom of the well. Sometimes pipe jams may occur during the process of pipe running. Use practice tongs to rotate slowly (the steel pipes are connected by electric welding back ribs). Go down to above the ground, then correct and fix it vertically, and evenly fill the space between the concrete flower tube (or steel pipe flower tube) and the original protective wall with the filter material (the gravel particle size is 10-20mm), and fill it up until it is filled. Use C15 concrete to seal, (the purpose of sealing the filter material with concrete is to prevent soil from entering the filter material). After the concrete has solidified, carry out earthwork backfilling and tamping treatment. When backfilling, pay attention to the concrete pipe (or steel pipe) and ramming at the same time. In order to ensure the vertical stability of the concrete pipe (or steel pipe), it has been rammed and filled to the ground. After the backfilling work is completed, the treatment of the wellhead platform will be carried out. After the treatment of the wellhead platform is completed, the pump can be used for pumping.
In the repair and reconstruction of motorized wells, in some places, only the original soil well wall above the water surface was treated, that is, the part above the water surface was treated with concrete pipes or steel pipes, while the part below the water surface was not treated, in order to save labor, money, The treatment process is simple. However, if the part below the water surface is not treated, it means that only half of the treatment has been done. Once an abnormality occurs in the underground during the operation of the pumped well, such as the original wall pipe dislocation or collapse, it cannot be repaired and can only be scrapped. Therefore, it must be processed to the bottom of the well, so that after the original protective wall pipe and the new protective wall pipe are packed and squeezed with surrounding rocks, they will not deform or move, and there is no danger of collapse.
In short, according to the above-mentioned DTH Bit maintenance and reconstruction construction method, the treatment method is simple, labor-saving, and investment saving. The repaired and reconstructed motorized well is the same as the newly drilled motorized well. It is safe and convenient to use, prolongs the service life of the motorized well, and is also for the society , Which has increased economic benefits for the masses.