The amount of bentonite used can be decreased by adding in polymers to help reduce the fluid loss while keeping the concentration of bentonite down. The coarser the soil, the more bentonite is required to ensure minimum fluid loss. The concentration of the bentonite fluid is determined by the soil. A bentonite-based drilling fluid is typically chosen for HDD bores, since it is able to provide all the functions listed above. The primary functions of a drilling fluid are. The drilling fluids have several functions that keep the hole open and stable in order to pull the pipe through with ease. In order to do this, one must look at the functions of the drilling fluids, the properties of the drilling fluids like viscosity and solids contentthe volume of fluids being pumped, and the rate or speed of drilling.ĭuring the drilling process, a contractor circulates drilling fluids through the bore. They were asked to provide details on the drilling fluid they were using and the expected annular pressure while drilling. A few years ago, I received a call from a contractor asking for help mitigating a situation with a governmental transport agency in regards to monitoring downhole pressures as they were drilling under a six-lane highway crossing.
