In building construction, piling is a very important project. Unstable foundation will affect a series of subsequent operations, so pile driving should be taken seriously. At present, there are many kinds of machinery used for piling, and rotary drilling rig is a typical one. So what is the rotary drilling rig for? What's the difference between rotary drilling rig and impact drilling rig? Let's have a look. 1. What is the rotary drilling rig used for?

Rotary drilling rig is also called rotary drilling rig and pile driver. Rotary drilling rig is a kind of construction machinery suitable for hole-forming operation in building foundation engineering. Widely used in municipal construction, highway bridges, high-rise buildings and other foundation construction projects, with different drilling tools, suitable for dry (short spiral), wet (rotary bucket) and rock (core drilling) hole-forming operations.

Rotary drilling rig is mainly suitable for the construction of sandy soil, cohesive soil, silty soil and other soil layers, and is widely used in the construction of cast-in-place piles, underground continuous walls and foundation reinforcement. The rated power of rotary drilling rig is generally 125 ~ 450 kW, the power output torque is120 ~ 400 kn m, the maximum aperture can reach 1.5 ~ 4m, and the maximum hole depth is 60 ~ 90m, which can meet the requirements of various large-scale foundation construction.

Rotary drilling rig has the characteristics of large installed power, large output torque, large axial pressure, flexibility, high construction efficiency and multifunction, and has been widely used in various bored pile projects.

Second, what is the impact drill used for?

Impact drilling rig is a kind of machinery that uses the impact force of drill bit to drill holes in rock stratum. It can adapt to all kinds of geological conditions, especially drilling in pebble bed, and it is more adaptable than other types of drilling rigs. The working principle of impact drilling rig is an engineering drilling rig equipment that drills holes by vertical reciprocating motion and relying on impact force, and its working principle is similar to that of hammer for rock drilling. It's all about punching holes by impact

Impact drilling rig is divided into full hydraulic impact drilling rig and pneumatic impact drilling rig, both of which are mechanical equipment for drilling rocks. Impact drilling rig is different from cutting drilling rig. Impact drilling rig is used to drill holes in rocks with Platts hardness above 7, such as limestone, granite and hard sandstone. The percussion drill uses an impactor (hydraulic or pneumatic) to break the rock at a high impact frequency per minute, and at the same time, it rotates to grind the rock into powder, and then uses gas or water to discharge the ash to achieve the drilling effect. Usually used in earth and stone engineering, mining, tunnel drilling and other drilling operations.

Third, the difference between rotary drilling rig and impact drilling rig

1, rotary drilling rig

Construction technology: the rotary drilling rig cuts into the soil layer by adjusting the drill pipe and cooperating with the rotation of the drill bit, and then the soil is lifted up by the drill barrel, and finally the hole is formed.

Scope of application:

(1) is suitable for various soil layers, sand layers, pebble layers, etc. It has the characteristics of fast pore-forming speed, convenient movement, little environmental pollution and low noise.

(2) The construction of rock stratum is difficult, and the length of drill pipe will limit the length and diameter of pile.

2. Impact drilling rig

Construction technology: hoist the impact hammer on the impact pile, make holes by the impact hammer's own weight, and protect the wall with mud.

Scope of application: It is suitable for the construction of various soil layers and rock strata, among which the construction in rock strata has great advantages, but it is necessary to set up a mud pool and a sedimentation tank, which has a general hole-forming speed and is easy to fall off the hammer. Large-aperture construction and reaming should be carried out in stages, and the impact vibration disturbance is great.