Our highly effective manual drilling techniques utilize innovative design, low-cost locally available materials, and easily transferable technology.
Manual drilling technology is designed to be affordable, portable, adaptable, and easily transferable. By meeting these criteria, opportunities are introduced into economically disadvantaged areas for business ownership that provides a necessary service. Protected boreholes can be expanded into remote rural areas inaccessible to expensive mechanized drill rigs. This extends all the advantages attendant to improved health as well as stimulating local economies.
The manual drilling method developed by Access Development uses a systematic combination of proven drilling methods, which have been scaled for human power. This approach combines the primary strengths of each method while remaining affordable and transferable. As wells are drilled, geological information is gathered in order to refine tool design which steadily increases efficiency. As a result, the standard drilling kit now consists of over 20 specialized tools that fall into three primary categories; turned, driven and dropped.
In the category of turned tools, Access Development kits includes soil, sand and stoney augers in diameters from 170mm to 100mm. This set of augers generally completes the majority of the borehole depth through unconsolidated zones due to their performance and versatility. As boreholes proceed below the static water line, a 125mm bailer is used in tandem with auger drilling to efficiently retrieve cuttings that may fall from the tool.
Driven tools were introduced to take over where the turned tools had difficulties advancing. When hard-packed clay or zones containing intermittent gravel are encountered, a reciprocating down-hole hammer can be fitted with a variety of bits to pile-drive into these more consolidated layers. The bit choices include clay-cutters, coring tubes, and chisels.
The historic cable tool drilling method inspired a set of tools when drillers encounter a confining layer of crystalline rock. Access Development provides both our “CAT Tooth” assembly for smaller scale drilling teams as well as a drop-center button bit for more advanced teams who encounter hard rock formations regularly.
Access Development drilling kit includes a tripod and winch assembly to aid drilling efforts, pulling of inoperable pumps and the removal of temporary casing. The standard mechanical advantage of 7 to 1 can be doubled with the use of a traveling pulley, which can assist in drilling efforts and the pulling of inoperable pumps.
This systematic method is capable of drilling and completing drinking water wells to 30 meters with a four person team in one week. The affordability and accessibility of Access Development’s hand-drilling tools allows for trained teams to have an opportunity to own and operate their own well-drilling businesses.