Baptist well drilling technology

The locally made equipment consists of a drill stem, which  is connected to a rope that is pulled by a number of people. The rope is led  via a pulley that is attached to a derrick of wooden poles. Herewith one drills  an open hole down into the aquifer, the layer of sand that is saturated with water, without a casing being used during drilling. The hole is made via hydraulic percussion of drill pipe and a drill bit with drilling fluid consisting of water and bentonite , clay or cow dung.  After the hole is completed and cleaned a casing is installed.

 

The drill stem is light weight and thus easy to lift and to transport, because the upper part is assembled from thick-walled PVC or Poly-Propylene pipes while only the lowest 3 m part of the drill pipe is from steel tube. The drill bit tool is a ball and dart point mounted on the end of the drill stem. As drilling proceeds 1.5 meter or 3 m lengths of PVC drill pipes are added as needed. The drill bit acts as a foot valve. Drilling fluid and cuttings enter the drill pipe through the valve. The cuttings are suspended in the fluid, forced up the drill pipe and discharged at surface. This via inertia and displacement of the drilling fluid, on each stroke.

The drilling fluid and cuttings flow into the settling pit. The heavier parts stay in the pit and the cleaner fluid enters again in the borehole. Baptist drilling is limited to non-cemented, sedimentary deposits of sand and clay (it will not drill through solid bed rock). Soft rocks can be drilled through, although slowly. Larger stones may cause problems. Manual drilling is done by 4-8 people and requires 1- 8 days per well depending on depth and soil conditions.

  

drilling

drillbits

Drilling performed, Nov 2006

Baptist drilling equipment

 In Bolivia, over 2000 wells have been drilled with this method, by family groups working together under guidance of one trained drilling specialist. The methodology is being spread out to various other countries in the world.