Siton DD21L is a low-profile single-boom face drilling rig designed for narrow-vein mining and underground development. The development drill covers drift cross sections ranging from 4.0 m(W) × 1.9 m(H) to 6.7 m(W) × 5.6 m(H). Its compact design, flexible drilling boom and articulated four-wheel-drive chassis support efficient drilling and maneuverability in confined underground spaces.

Features & benefits

1.Hydraulic Rock Drill

The DD21L face drill rig comes standard with the Woserld A18D/L 18kW hydraulic rock drill, with 20 kW, 22 kW and 25 kW rock drills available as options for different rock conditions and drilling requirements. The drilling system supports hole diameters from 43 mm to 76 mm and drilling depths of up to 3.4 m, with penetration rates ranging from 0.8 to 3 m/min. Its double-damping system helps extend rock drill service life and reduce rock tool consumption, contributing to lower operating costs.

2.Compact Low-profile Design

Designed specifically for low-profile underground operations, the DD21L face drill jumbo features a compact structure that allows efficient operation in confined working areas. The DD21L underground drill rig weighs 13.85 tonnes and measures 11.9 m in length and 2.19 m in width. Its retractable canopy lowers the machine height to just 1.57 m and reaches 2.27 m when fully raised, enabling the drilling rig machine to operate underground workings with varying headroom.

3.Long-reach Boom with Automatic Hydraulic Parallelism

The DD21L ultra-low profile drill rig features a long drilling boom with a fully hydraulic parallel-holding system. The system automatically maintains the alignment of the feed during boom movement, supporting fast and accurate hole positioning. The boom provides a telescopic extension of 1,400 mm, while the feed offers 1,250 mm of compensation and 360° rotation. This provides a wide coverage area and flexible adaptability to various drift profiles and cross-cutting layouts.

4.Hydraulic Control System

Key hydraulic components are sourced from world-renowned brands, paired with a premium international piston pump control system for reliable performance and extended service life. Automatic anti-jamming and drill rod retraction functions help protect the rock drill and drilling tools when abnormal resistance is encountered. These functions reduce rock tool consumption and unplanned downtime while improving drilling efficiency. An optional centralized lubrication system simplifies routine lubrication and maintenance.

5.Heavy-duty Articulated Chassis

The DD21L low profile underground drill rig is built on a heavy-duty articulated chassis with four-wheel drive and a steering angle of ±40°. This development drill rig has an inner turning radius of 2.6 m and an outer turning radius of 5.6 m, providing good maneuverability in narrow underground drifts. With a maximum gradeability of 14° and a maximum tramming speed of 10 km/h, the chassis delivers stable tramming and flexible relocation between working areas.

6.FOPS Safety Canopy

Given the inherent risks associated with drilling operations, such as falling rocks, equipment rollover, it is crucial to ensure the safety of operators. Siton addresses these concerns by equipping our narrow vein drilling jumbos with canopy certified for FOPS (Falling Object Protective Structure). The retractable canopy design enables safe travel through low-headroom excavations without compromising operator comfort during drilling.

7.Optional Safety Features

For additional protection, the DD21L face drilling jumbo can be equipped with an ANSUL automatic fire suppression system, further enhancing safety in underground mining operations.