Bolivian Baptist Well Drilling

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Bolivian Baptist Well Drilling

• Author of the system Terry Waller

• 1,500 wells drilled in 5 years (more than 200
  in 2004).
• Very simple and cheap equipment. Can be made
  in any basic workshop. Complete set costs
  approx. 300.
• Drills even light rock.
• Done by the users themselves with little
  technical assistance.
• Users teach others how to drill their own wells.

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Bolivian Baptist Well Drilling
General View
Rope to pulley (no need for a formal drilling
tower).
Workers pulling up the drilling tool (use of a
lever is not usual)
Drilling liquid (light mud) is expulsed from the
drilling rod itself (no need for a mud pump)
Drilling stem of thick PVC pipe (
light). (makes it possible to drill deep without
a lever to lift the drill tool and to easily
adapt stroke length to conditions)
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Bolivian Baptist Well Drilling
The Drill Bit
Coupling to main pipe of drilling tool (3 metres
of 1.25 galvanized iron water pipe)
Internal check valve expulses the mud, loaded
with clippings through the drill stem with each
stroke.
Dart mounted on ball that acts as check valve
assures self-cleaning of mud inlet.
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Bolivian Baptist Well Drilling
Starting the drilling
Drilling fluid (mud) expulsed from the drilling
tool itself through its vertical movement.
Long drilling tool (3 m) should be entered
perfectly vertically (two helpers watching to get
it right).
Vertical hammering only. There is no rotating
action.
Sedimentation pit. Heavy particles sink to the
bottom. Light drilling liquid (mud)
re-circulates back into the borehole by gravity.
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Sometimes shallow water holding layers would
yield undesirable water. To prevent such water
from entering the well, soon after completing the
drilling, the borehole is cased with a PVC tube,
wide enough to accommodate the pump. This also
prevents it from caving in.
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Bolivian Baptist Well Drilling

• Main Characteristics

• Pure impact action (no rotating movement).
• Absence of torque permits a light drilling stem
  (thick PVC pipe).
• Light drilling stem permits working the tool
  with a simple pulley fixed to any kind of
  tripod or crossbeam.
• Clippings pumped out by movement of the drill
  tool itself.
• No need for a separate mud pump.

Advantages
Drawbacks

• Very simple and cheap equipment.
• No need for mud pump or tower.
• Permits long extensions of drill stem.
• Caving resistant borehole.
• Easy to vulgarize.
• Mechanizable.

• Somewhat slower than drilling with rotating
  action.
• PVC drill stem should be high quality.
• Some exercise needed to get the long drill tool
  right at start of drilling.
• In wells gt 20 metres, needs a lot of manpower
  to pull the rope.

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Bolivian Baptist Well Drilling

• Variants

Rock bits (without points, otherwise they get
stuck edge reinforced with high carbon electrode
welding)
Fixed head drilling bit
Check valve inside tool
Classical dart bit
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Bolivian Baptist Well Drilling

• Variants

Since there is only vertical move-ment (no
rotation), the process can be mechanized. (When
labour is in short supply and a lot of wells to
be drilled).
Turning lever with pulley, moved by the engine,
pulls the rope. (Stroke height is adjusted by
free length of the rope and position of pulley on
the lever.)
3 HP Diesel Engine.
Reduction of engine RPM.
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Bolivian Baptist Well Drilling

• More information

http//www.geocities.com/h2oclubs/