DESIGN AND FABRICATION OF A PORTABLE DRILLING RIG FOR AGRICULTURAL IRRIGATION BOREHOLES

Access to affordable groundwater extraction technologies remains a major challenge in many rural, where conventional rotary drilling rigs are often impractical due to high cost, technical complexity, and intensive maintenance requirements. This study presents the design, fabrication, and experimental evaluation of a low-cost, mechanically simple, and locally manufacturable portable drilling rig intended for residential boreholes and small-scale agricultural irrigation. The rig was engineered to balance drilling performance with affordability by using readily available materials and straightforward mechanical components, enabling ease of replication, operation, and maintenance in resource-constrained settings. Experimental evaluations were conducted in sandy, clayey, loamy, and gravelly soils at varying rotational speeds, with penetration rate, torque, power consumption, and drilling efficiency recorded. The prototype achieved optimal performance in sandy formations, reaching a penetration rate of 18.3 cm/min, a torque of 45 Nm, and power consumption of 1.6 kW, while cohesive and coarse soils required higher torque and energy input. Comparative benchmarking against commercial systems Hydra-Drill MUD-2, LoneStar LS100, and PAT-301T showed that although the prototype exhibited lower penetration rates (0.95–1.25 m/hr versus 2.1–3.5 m/hr) and shallower depth capability (up to 22 m), it demonstrated superior energy efficiency (0.06–0.14 kWh/m compared with 0.14–0.33 kWh/m), enhanced portability, rapid setup, and significantly lower operational costs. Overall, the results indicate that the proposed system is a viable and sustainable solution for shallow to moderate borehole drilling. Future work will focus on hydraulic assistance, modular power integration, and sensor-based torque control to improve adaptability across diverse geological conditions.