Rock Drill
Overview
Pneumatic rock drills are powered by compressed air and deliver impact force through piston reciprocation to fracture rock efficiently. They are robust, built for harsh conditions, and widely used in mining, tunneling, and civil engineering. The petrol-driven (internal combustion) rock drill offers independent mobility and is ideal for remote field operations.
High-performance Rock Drills for Mining, Tunneling & Field Operations Reliable pneumatic and petrol-powered rock drills engineered for harsh environments — high impact energy, easy maintenance, and portability.
Key highlights
Powerful impact performance for medium to extremely hard rock
Dust suppression & low-vibration options for safer work environments
Portable petrol-powered option for remote sites without compressed air or electricity
Models & Technical Specifications
Key Specifications
Weight: 26 kg
Overall Length: 661 mm
Piston Diameter: 80 mm; Stroke: 60 mm
Shank: H22 × 108 mm (hex shank, standard chisel)
Bore Diameter: 34–42 mm (optimal 38 mm)
Impact Frequency: ≥36 Hz (~2,160 bpm)
Impact Energy: ≥50 J
Air Consumption: ≤65 L/s
Applicable Rock Hardness: Medium to hard (Petersen hardness f = 8–18)
Operating Air Pressure: 0.5–0.6 MPa (minimum start 0.4 MPa)
Core Features
Single-stage leg design with adjustable thrust (0–12 kN) for steady feed force; single-operator capable — ideal for heading and anchor installation.
Precision piston-cylinder fit for high impact efficiency; effective drilling depth up to 5 m. Cylinder made of wear-resistant alloy for extended service life.
Low maintenance: recommend clearing rock chips from the cylinder every 4 hours and weekly lubrication of the shank sleeve.
Built-in silencer reduces noise by ~15% vs. conventional models. Optional automatic dust/rock powder evacuation available.
Typical Applications
Suitable for horizontal or inclined drilling (0–45°) — tunnel headings, blast-hole drilling in tunnel excavation, anchor holes in coal and metal mines, and shallow slope reinforcement for rail and road projects.
Key Specifications
Weight: 24 kg
Overall Length: 628 mm
Cylinder Diameter: 76 mm; Piston Stroke: 55 mm
Shank: H22 × 108 mm
Impact Energy: ≥65 J
Impact Frequency: ≥38 Hz (~2,280 bpm)
Air Consumption: ≤80 L/s
Drilling Depth: 5 m
Bore Diameter: 32–40 mm
Applicable Rock Hardness: Medium to extremely hard (f = 8–20)
Operating Air Pressure: 0.55–0.65 MPa
Required Supply: Air compressor rated ≥10 m³/min
Core Features
Higher impact energy and frequency deliver 20–30% faster drilling rates vs. YT28 under similar conditions.
Air–water dust suppression system: compressed air drives water into the hole to wet and remove cuttings — reduces airborne dust by over 60%. Air–water ratio adjustable to suit rock conditions.
Symmetric buffering reduces vibration by ~25%; anti-slip and shock-absorbing handle improves operator comfort.
Dual-stage telescopic leg provides wider support range for varied working spaces. Excellent sealing enables stable operation in wet and dusty conditions.
Typical Applications
Recommended for medium-depth drilling in major civil works — tunneling, roadbed blasting, dam foundations — and for hard rock such as granite and quartzite in underground and open-pit mining.
Key Specifications
Weight (incl. fuel): 27 kg
Power Source: Single-cylinder, air-cooled two-stroke petrol engine (bore 27 mm, stroke 24 mm)
Rated Power: 1.8 kW @ 6,500 rpm
Fuel Tank Capacity: 1.14 L (use ≥92# gasoline; mix with two-stroke oil at 50:1)
Drilling Rate: ≥250 mm/min on rock f = 10
Impact Frequency: ≥30 Hz (~1,800 bpm)
Impact Energy: ≥45 J
Bore Diameter: 30–45 mm
Drilling Depth: ≤4 m
Operating Temperature Range: -40°C to +40°C
Core Features
Self-contained power source — no external air or electrical supply required, ideal for remote field operations.
Forced air-cooling for sustained operation; automatic decompression valve reduces starting effort.
Lightweight aluminum alloy body with durable alloy piston — service life up to ~800 operating hours.
Higher noise and vibration (approx. 105 dB) — personal hearing protection required. Includes fuel gauge and engine oil alarm options.
Typical Applications
Field operations lacking compressed air or mains power: demolition, geological shallow-sampling, roadside/remote blasting holes, emergency rescue debris clearance, and small-scale civil stonework.
Selection Guide
Medium-hard rock (f = 8–12): YT28 or 7655. YT28 for cost-effectiveness; 7655 when productivity is paramount. If no compressed air availability, choose YN27C.
Very hard rock (f > 12): Prefer 7655 for higher impact energy (≥65 J). For small jobs consider an electric model with reduced drilling speed to prolong service life.
Soft rock (f < 8): Lightweight models (YT28) recommended to reduce operator fatigue.
Confined headings (≤3 m × 3 m): Compact units such as YT28 for flexible maneuvering.
Dusty/wet environments: 7655 with air–water dust suppression and robust sealing.
No power/air supply: Choose petrol-driven YN27C.
Low-noise or environmental constraints: Electric models preferred.
Operation & Safety Highlights
Pneumatic units
Maintain compressor pressure within the recommended range (0.5–0.65 MPa). Inspect hoses and fittings for leaks.
Use HJ40 mechanical oil in lubricators; maintain oil level.
Start with low airflow to align the chisel, then increase to full air to avoid dry striking.
Clear cylinder chips regularly and stop the machine if abnormal vibration or noise occurs.
Petrol units
Mix fuel at 50:1, check fuel system for leaks, inspect spark plug gap (0.6–0.8 mm).
Starting: close choke, pull recoil until resistance, then brisk pull; warm up for 3–5 minutes after start.
Use PPE: anti-vibration gloves, hearing protection, dust mask. Avoid fuel spills.
Electric units
Ensure stable voltage (±10%), intact cable insulation, and reliable grounding. Avoid wet operation.
Stop if the motor temperature exceeds safe limits (>60°C).
Maintenance Schedule
Daily: Surface cleaning, bolt check, lubrication/fuel/oil level inspection.
Weekly: Inspect shank sleeve and piston wear; clean cylinders and filters; top-up grease/oil.
Monthly: Disassemble critical components (cylinders, gearboxes) for inspection, replace worn parts, recalibrate impact frequency and drilling speed.
FAQs
Q:What drilling depth and hole diameters are supported?
A: Pneumatic models: up to 5 m (YT28/7655). Petrol: up to 4 m. Refer to model specs for diameters (YT28: 34–42 mm; 7655: 32–40 mm; YN27C: 30–45 mm).
Q: What are the spare parts replacement intervals?
A: Depends on usage. Weekly inspection of shank sleeves, seals, and buffers recommended. For heavy-duty use, replace consumables every 1–3 months. Spare kits available.
Q:Can the drills be customized (special shank, noise reduction, extended leg)?
A: Customizations are supported (shank sizes, silencers, auto dust ejection, etc.). Please submit detailed requirements for engineering review and quotation.