WR400S

💧 WR400S 400 m Telescopic Mast Crawler Water Well Drilling Rig

The WR400S is a telescopic mast crawler water well drilling rig that combines 400 m drilling depth, 6 m drill pipe capability, and transport convenience. The S in the model stands for telescopic mast. Compared with a conventional fixed mast structure, it can shorten the overall transport profile while still supporting direct operation with 6 m drill pipes or 6 m casing in working condition. This makes it better suited to water well drilling crews that need frequent truck loading and relocation but also want to reduce the number of pipe connections.

🪜 The telescopic mast is the core structural feature of the WR400S

The value of the telescopic mast lies mainly in the balance between transport and operation. During relocation, the mast can be shortened to reduce the transport profile and lower the difficulty of loading, road passage, and site turning. After reaching the hole position, it can be extended to working condition and continue to maintain 6 m drill pipe operation capability. For cross-regional drilling, village and township projects, and continuous work across multiple sites, this structure makes transport arrangements more convenient.

🔩 Direct use of 6 m drill pipes or 6 m casing reduces make-up and break-out frequency

The WR400S supports direct operation with 6 m drill pipes and 6 m casing, with recommended drill pipe diameters of 89 / 102 mm. Long drill pipes can significantly reduce the number of pipe connections in 300–400 m water wells, lowering auxiliary time and the frequency of manual handling. For projects requiring continuous footage, reducing pipe make-up and break-out often improves the actual construction rhythm more than simply increasing fast-action speed.

📏 400 m-class drilling depth is suitable for medium-deep groundwater development

With a maximum drilling depth of 400 m and a borehole diameter of 105–325 mm, it can cover a large number of rural, agricultural, industrial, and general engineering water well needs. In areas where shallow groundwater is unstable, the water table is relatively deep, or greater water-finding margin is needed, a 400 m-class rig offers a wider construction range than small shallow well rigs. The actual completed well depth should still be determined according to hydrogeological conditions.

🌾 Farmland irrigation and large-scale planting projects

The WR400S is suitable for irrigation well construction in farmland, orchards, greenhouses, and nurseries. Large-scale agricultural projects often require continuous construction of multiple water wells. The 6 m drill pipe can reduce pipe connection frequency, while the crawler chassis makes it convenient to move on field roads and general unpaved sites. Well diameter and pump type should be designed according to planned water output and irrigation area.

🏠 Rural water supply and small community water wells

In villages where centralized water supply coverage is insufficient or groundwater is relatively deep, the WR400S can be used for household water wells, village-level water supply wells, and small public water source wells for schools, clinics, and similar facilities. The 400 m-class drilling depth provides greater space for finding aquifers, but the target well depth should still be reasonably determined based on local hydrological data before formal construction.

🐄 Livestock farms, ranches, and agricultural production water

Livestock farms and ranches require long-term stable water sources for drinking, cleaning, and production. The WR400S can be used for livestock water wells and remote agricultural projects. Diesel power does not rely on a fixed power grid, making it suitable for construction sites far from towns. For long-term pumping wells, well casing, screen pipes, and pump configuration should be designed according to the water-producing layer.

🏭 Industrial and construction site water supply

Factories, workshops, construction camps, and infrastructure projects may also require independent groundwater sources. The WR400S can be used for general production auxiliary water, construction water supply, and site service water wells. In environments with limited space in factory areas, enclosures, and roads, the telescopic mast offers more advantages for transport and site access.

💪 22 T lifting force provides margin for drill string and casing handling in medium-deep holes

The equipment has a lifting force of 22 T and an axial pressure of 4 T. In 400 m-class boreholes, drill pipe weight, borehole wall friction, and casing weight all gradually increase, so greater lifting capacity is beneficial for normal tripping and tool recovery. If abnormal resistance occurs during pull-out, the hole should first be cleaned and the presence of underreaming, falling blocks, or stuck tools should be assessed. Maximum lifting force should not be used directly to force handling.

🔄 8000 / 4000 N·m dual-condition rotary system

The rotary system has a maximum torque of 8000 / 4000 N·m, corresponding to maximum speeds of 75 / 150 r/min. The low-speed high-torque condition is more suitable for larger diameters and higher-resistance conditions, while the higher-speed condition is suitable for drilling stages with lower resistance. During construction, switching should be based on drilling tools, rock formations, and cuttings return conditions rather than maintaining a single condition for a long time.

🚀 29 m/min fast lifting and 56 m/min fast feed

Fast lifting and feed are mainly used for power head return, drill pipe handling, and non-drilling actions, which can reduce auxiliary time. Actual formation penetration efficiency still depends on rock hardness, borehole diameter, bit, DTH hammer, and air compressor capacity. Long drill pipes combined with fast hydraulic actions can further reduce ineffective working time.

💨 1.2–3.5 MPa working air pressure is suitable for medium- and high-pressure DTH drilling

When using a DTH hammer, the recommended working air pressure is 1.2–3.5 MPa, with an air consumption of 16–55 m³/min, compatible with medium- and high-pressure series DTH hammers. Air compressor selection needs to consider both pressure and displacement. Especially in large-diameter, hard rock, and high-altitude environments, insufficient displacement will directly affect impact and cuttings removal.

💎 DTH hammer drilling can be used in complete hard rock

After entering relatively complete rock formations such as limestone, sandstone, and granite, DTH hammer pneumatic drilling can be used. Hard rock construction should ensure DTH hammer lubrication and sufficient air volume, and regularly check bit wear. If cuttings return suddenly decreases or air pressure is abnormal, the hole should be cleaned in time to prevent cuttings accumulation at the bottom and drilling tool sticking.

🌧️ Mud drilling can be used in soil, clay, and sand layers

Data shows that the WR400S also supports mud drilling. For soil, clay, sand, and other loose overburden layers, mud circulation can help with wall protection and cuttings carrying. After the upper loose layer is stabilized, entering the rock layer with a DTH hammer can better balance hole stability and hard rock drilling efficiency.

🌦️ Weathered rock and alternating soft-hard formations

Weathered rock often has faster penetration, but the borehole wall is prone to falling blocks and underreaming. When soft and hard layers alternate, rotary torque and penetration rate change frequently, so feed and rotation speed should be adjusted according to drilling tool load. When the upper unstable hole section is thick, follow-up casing can be considered to reduce borehole wall problems in the deep hole stage.

🧱 Fracture zones, fissures, and air-loss formations

Fissures and broken formations may cause air loss, sticking, and falling blocks. During construction, excessively fast feed should be reduced, continuous hole cleaning should be maintained, and foam or casing should be selected according to actual conditions. If air loss is severe, simply increasing air compressor pressure is not enough; the presence of large fissures or cavities also needs to be assessed.

💧 Aquifers and strong water inflow sections

After entering the main aquifer, groundwater will change DTH hammer cuttings removal and working conditions. Aquifer depth should be recorded in time, and air supply and hole cleaning methods should be adjusted according to water inflow. During well completion, well casing, screen pipes, and sealing sections should be reasonably arranged to ensure long-term pumping performance.

🚜 Crawler chassis is suitable for rural areas, construction sites, and general field sites

The equipment walking speed is about 2.5 km/h, and the maximum climbing angle is approximately 21°. The crawler structure is suitable for rural roads, gravel ground, and generally uneven sites. Before relocation, the mast should be in a safe transport state, and ground bearing capacity, slope, and wet slippery conditions should be assessed to avoid heavy equipment sinking on soft ground.

🦵 1.6 m hydraulic outriggers improve drilling stability

The hydraulic outrigger stroke is 1.6 m, which can be used for equipment leveling and stable support. 400 m-class water well construction has a relatively long cycle, and the level state of the equipment affects hole deviation and mast stress. On soft ground, pads should be used to ensure even outrigger force and avoid settlement during construction.

⚡ 92 kW Yuchai engine meets continuous water well construction

The WR400S uses a 92 kW Yuchai engine to provide power for rotation, feed, crawler walking, and auxiliary hydraulic systems. During long-term hard rock construction, focus should be placed on checking engine cooling, air filters, and hydraulic oil temperature. Dusty sites require more frequent cleaning of radiators and filter elements.

🧵 1.5 T auxiliary winch reduces labor intensity in drilling tool handling

The auxiliary winch has a lifting force of 1.5 T and can be used to handle DTH hammers, drill pipes, casing tools, and other site accessories. When using long drill pipes and long casing, reasonable lifting points and manual guidance should be used to avoid lateral swinging of drill pipes or collision with the mast.

📦 Telescopic mast facilitates truck loading and cross-site transport

The overall weight is about 9.8 T, and the overall dimensions are about 6.26 × 1.85 × 2.43 m. Compared with a fixed long mast, the telescopic structure can improve the transport profile and is more suitable for drilling crews that need frequent truck loading. During transport, still check mast locking, equipment fixing points, and separate bundling of drill pipes.

🧰 Mud pump, centrifugal pump, generator, and foam pump are optional

Mud pumps, centrifugal pumps, generators, and foam pumps can be selected according to the project. Loose layer projects need a mud system more, hard rock projects focus on configuring air compressors and DTH hammers, and formations with severe air loss may use foam assistance. Configuring accessories according to actual working conditions is more conducive to controlling equipment investment.

⚠️ Key points for daily inspection of the telescopic mast

In addition to routine inspection of the engine, hydraulic system, crawler, outriggers, and drilling tools, the WR400S should also focus on inspecting the telescopic mast guide rails, hydraulic cylinders, pins, and locking structure. When using 6 m drill pipes or casing, ensure the mast is fully extended and reliably fixed, and avoid drilling and drill pipe handling in an unlocked state.

Due to differences in actual geological conditions, downhole tools, drilling angle, and operating methods, the final drilling efficiency, drilling depth, and well completion effect should be based on on-site working conditions.

📊 Main technical parameters