Drilling a formation into holes from the ground using mechanical equipment or manpower is called drilling. Drilling is widely used in economic construction.
In addition to obtaining groundwater, some wells are drilled to detect hydrogeological conditions.
The purpose of hydrogeological drilling is to find out the water quality and quantity of groundwater in a certain area, as well as the movement of groundwater and other hydrogeological conditions.In drilling, not only rock samples and water samples are obtained, but also need to do water tests.Some bore holes are left for long-term observation after drilling, which becomes a point of hydrogeology investigation.
In addition, in accordance with the spirit of combination of exploration and exploitation and according to actual needs, after hydrogeological investigation was carried out, the human well pipe and the corresponding filter pipe became wells and were used as groundwater exploitation Wells.In most cases, in order to develop groundwater resources, groundwater wells need to be specially drilled.
There are 2 kinds of drill bits for water well drilling: one is impact drill bit ,the other is rotary drill bit.
Impact drill bit also be called DTH drill bit.Wire rope is used to send the drilling bit to the bottom of the well, and the beam mechanism is driven by the power, which makes one end of the beam move up and down, and drives the wire rope and the bit to have up and down impact effect, so that the rock is broken.With DTH drill bit,the drilling speed is slow, and efficiency is low, which couldn’t adapt to the increasing well depth and complex formation drilling requirements.So it be gradually replaced by rotary drill bits.However due to the advantages of simple structure,low cost and no pollution to reservoir etc,it can be used in some shallow and low-pressure wells.
Rotary drill bit break rocks by cutting and grinding action generated by rotating itself.Rotary drill bit is the most poplar drill bit in drilling.Its drilling speed is faster than DTH drill bit,besides, with rotary drill bit, it is easy to deal with complex situations such as well collapse and blowout.