For my white sandstone, limestone and red sandstone, core drilling rig and Extension Drilling Tools are faster, and the hole neck 275 is enough. The trouble masters are talking about what rock formations and what drill bit is faster
Extension Drilling Tools is to drill into the ground. Water will flow out from the hole in the future, and the pipe will become a well.
When drilling down, there is a drill bit at the bottom of the drill rod. There are several models of this drill bit. It is very hard. It must be lighter to grind the rock into powder. The rock in the middle does not need to be ground. It will be lifted from the drill rod. .
During the Reaming Bit drilling process, the drilling machine drives the drill pipe and the drill bit to rotate at high speed and pressurize downwards. These two forces act on the rock to grind the rock in contact with the front of the drill bit into powder. The water filled the surface and drained away.