Water Well Rig Configuration for Dispersed Borehole Programs

Working condition profile

Dispersed water supply programs mix shallow weathered overburden, sand and gravel with deeper bedrock aquifers several hundred meters down. Typical village and livestock boreholes run 150-400 m, while deeper aquifer and irrigation wells can reach 2500 m. Sites are small and connected by local roads and narrow tracks, and field service support is often limited, so equipment must be simple for a small crew to operate, transport on light trucks, and maintain with commonly available wearing parts. The geology also demands multi-method capability: mud rotary in soft overburden and air DTH percussion in hard weathered rock, so casing and screen installation can follow without changing rigs.

Equipment selection

For the bulk of shallow village and livestock boreholes, the configuration uses the mechanical-hydraulic water well drilling rig ST-400, rated to 400 m maximum water well depth, with a 3200 N-m maximum spindle torque, 55 kN lifting force, and a choice of 45 kW electric motor or 58 kW diesel engine. At only 2200 kg and 2800 x 1100 x 2100 mm, it fits on a light truck and into tight sites, drilling through soil, sand, gravel, weathered rock, and soft-to-medium-hard formations.

For deeper aquifer and irrigation wells, the configuration adds the truck-mounted light drilling rig SY-T2500, rated to 2500 m nominal depth on 4 1/2 inch drill pipe with a 1200 kN maximum hook load, a 405 kW deck engine, and a top drive delivering 24000 N-m low-gear torque. It supports mud rotary, DTH air percussion, foam, and reverse circulation drilling, and travels on roads at up to 85 km/h. Both rigs are part of the broader truck-mounted drilling rigs and light rig offering.

Configuration & key specifications

Key specifications below are verified against published product data for the two rig models.

Delivery & field capability

The light ST-400 rig serves as the workhorse for the dispersed shallow program, where its small footprint and simple electric-or-diesel power choice keep mobilization cost low. The truck-mounted SY-T2500 drives itself between towns at up to 85 km/h, so one crew can move to the next borehole without dismantling the rig. Standardized hydraulic and wearing parts keep spare-parts inventory simple, and the multi-technique drilling capability means a second rig is not needed when geology switches from overburden to hard rock. Export documentation, including certificates of origin, can be prepared for customs clearance.