Water Well Drill Rig
Rotary drilling rig
The drilling hole is formed by breaking the rock stratum by the rotary movement of the drilling tool. The main types of drilling machines are large and small pot cone drilling machines, positive and reverse circulation rotary table drilling machines, hydraulic power head drilling machines, and down hole vibration rotary drilling machines. The simple rotary drilling machine only has drilling device, and the well drilling machine with perfect structure consists of drilling device and circulation well washing device. Drilling tools of rotary table well drilling machine include drill pipe and drill bit. The diameter of commonly used drill pipe is 60, 73, 89 and 114 mm. The drill bit is divided into two categories: full drilling bit and ring drill bit.
Large and small cone drills
The conical drilling tool is used for rotary cutting of soil layer. According to the size of drilling tools, they are called big pot cone and small pot cone, which can be driven by manpower or power. The cut soil scraps fall into the pot and are lifted to the ground for discharge. The structure is simple and the work efficiency is low. It can only be used in the general soil layer or the stratum with sand pebble diameter less than 10 cm and content less than 50%. The hole diameter of small cone is 0.55M, and the drilling depth is 80-100m; The diameter of the hole is 1.1m and the drilling depth is 30-40m.
Rotary drilling rig for well washing with positive circulation mud
It is composed of tower, winch, rotary table, drilling tool, mud pump, tap and motor. During the operation, the rotary table is driven by the power machine through the transmission device, and the drill bit is driven by the active drill pipe to rotate at the speed of 30 ~ 90 rpm to break the rock stratum. The mud is pumped and pressurized by the mud pump, then it is pressed into the hollow drill pipe through the tap above the drill pipe, flows down into the drill bit, and is ejected from the nozzle to cool and lubricate the drill bit; Bottom hole cuttings are brought out of the wellhead through the annular channel outside the drill pipe. After settling in the sedimentation tank, the mud flows back to the mud tank for recycling.
Reverse circulation mud washing rotary drilling rig
The drilling mode and structure are basically the same as the above, but the circulation mode of mud is opposite. After settling in the settling tank, the mud flows into the bottom of the well from the wellhead, and the mud carrying cuttings is pumped out of the well by the sand pump through the drill nozzle through the inner cavity of the drill pipe and back to the settling tank. This way is called pumping reverse circulation. The pump can also be used to inject the pressurized water from the bottom of the well into the inner cavity of the drill pipe through the nozzle to form the rising water carrying cuttings, which is called jet reverse circulation. The drilling machine can form a very high rising velocity in the drill pipe, and has a strong ability to discharge rock cuttings and pebbles, so the drilling speed is faster. It is suitable for soil layer, general sand layer and loose formation where the diameter of pebble is smaller than the inner diameter of drill pipe. The inner diameter of drill pipe used is larger, generally 150-200 mm, and the maximum is 300 mm. However, due to the limitation of pump suction or pressure delivery capacity, the drilling depth is generally less than 150 meters, and the chip removal efficiency is higher when the well depth is less than 50 meters.
Rotary drilling rig for compressed air well flushing
It uses air compressor instead of mud pump and compressed air instead of mud to wash well on rotary drilling rig. Reverse circulation is usually used, also known as gas lift reverse circulation. That is, the compressed air is sent to the air-water mixing chamber in the well through the air supply pipeline to mix with the water flow in the drill pipe to form the aerated water flow with the specific gravity less than 1. Under the gravity action of the annular water column around the drill pipe, the aerated water in the drill pipe carries cuttings up and out of the well, flows into the sedimentation tank, and the water after sedimentation flows back to the well by gravity. When the well depth is more than 50 meters, the cuttings removal capacity of this kind of drilling rig is greater than that of the drilling rig with pump suction or jet reverse circulation, so it is suitable for the situation of large well depth, arid area with water shortage and frozen soil layer in cold zone.(some rotary drilling rigs are equipped with mud pump and air compressor at the same time, so different well washing methods can be selected according to the situation.)
Hydraulic power head drill
A kind of rotary drilling rig. It is driven by hydraulic motor through reducer, and the power head moving up and down along the tower replaces the turntable and faucet on the rotary drilling rig to drive the drill pipe and drill bit to rotate and cut rock strata. Large diameter water wells can be drilled with a large drill bit with a diameter of 1m. It is characterized by fast drilling speed, simple assembly and disassembly of drilling tools and running of well pipes, no need to lift drilling tools when lengthening drill pipes, and a series of components such as hoists, lifting blocks, turntables, taps and Kelly are avoided.
Down the hole vibration rotary drilling machine
It is a kind of rotary drilling rig which combines vibration and rotary motion to drill rock stratum. The drilling tool is composed of drill bit, vibrator, vibration eliminator and guide cylinder. The exciting force produced by the vibrator makes the whole drilling tool swing. The drill bit is sheathed outside the shell of the vibrator through the friction ring. On the one hand, it vibrates with the vibrator in a horizontal circle with a frequency of about 1000 rpm and an amplitude of about 9 mm; On the other hand, it makes a low-speed rotation movement of 3-12 RPM around the axis of the vibrator to break the rock, while the drill pipe does not rotate, and uses the vibration eliminator to avoid transmitting the vibration to the drill pipe. The compressed air reverse circulation method is used to wash the well, so that the cuttings are discharged out of the well through the pipe and drill pipe cavity in the center of the vibrator. This kind of drill has simple structure and high drilling efficiency. The hole diameter is about 600mm and the drilling depth can reach