Bridge pile foundation construction equipment

It is an important substitute for other piling equipment under complex formation conditions such as ultra-large diameter and ultra-deep aperture or hard rock. The drill can be drilled in a variety of formations with compressed air gas lift reverse circulation.

The so-called gas lift reverse circulation drilling means that compressed air is sent to a certain depth in the well along the double-wall drilling pipe through the mixer injection pipe and mixed with circulating liquid. As the density of the mixed liquid is lower than that of the washout fluid, there is a pressure difference between the wellbore and the slag discharge pipe, and under the action of the wellbore liquid column pressure, the mixed gas and liquid in the pulp discharge pipe flow upward at a higher speed. Thus, the core or cuttings at the bottom of the hole are continuously discharged to the surface. The three phases of gas, liquid and solid flowing through the reverse circulation vibrating screen are discharged into the sedimentation tank. The settled mud flows back into the hole to replenish the circulating fluid space, so that the continuous drilling process is formed. The drilling method has the advantages of strong cuttings removal ability, not easy to plug, small equipment wear, long bit life, high drilling efficiency, good hole forming quality, and less hole wall collapse in loose formation.

Gas lift reverse circulation drilling tools include: liquid-gas separation device, liquid-gas output hose, gas faucet, double-wall drill pipe, gas-water mixer, single-wall drill pipe, centralizer, and drill bit, etc.