Soft coal and coal-rock mixed strata are very common in underground coal mines. Traditional blasting and manual excavation often cause unstable tunneling, poor roadway shaping and slow progress. The milling excavator, also known as tunnel miller, is widely used in these complex mine conditions. It supports safe, fast and precise mechanical tunneling without blasting.

This article lists the most practical application scenarios of tunnel millers in soft coal and coal-rock mixed working faces.

1. Rapid Tunneling in Pure Soft Coal Roadway

Soft coal seams are loose and easy to collapse during construction. Blasting easily causes over-excavation, coal falling and roof safety risks.

Equipped with continuous rotary cutting drums, the tunnel miller peels coal evenly. It effectively avoids large-area collapse and irregular sections. The whole cutting and mucking process is continuous and stable. Electric explosion-proof models fully meet underground coal mine standards for long-time non-stop operation.

2. Tunneling for Coal-Rock Mixed & Half-Coal Roadway

Most mine roadways feature alternating soft coal and hard rock layers. Traditional construction cannot adapt to uneven strata, resulting in low efficiency and rough roadway walls.

The tunnel miller fits mixed coal-rock conditions perfectly. It cuts soft coal fast and crushes sporadic hard rock stably in one pass. No frequent equipment replacement or procedure switching is needed. It greatly improves tunneling continuity in mixed-stratum roadways.

3. Fault Zone and Broken Soft Stratum Crossing

Fault zones have broken, loose and unstable surrounding rock. Blasting vibration easily triggers roof falling and side collapse.

Tunnel miller adopts low-disturbance mechanical cutting. It mills broken coal and rock layer by layer with minimal stratum impact. It stabilizes surrounding rock effectively and ensures safe crossing of fault and broken zones.

4. Roadway Trimming, Widening and Renovation

Soft coal roadways usually have irregular walls, over-excavation and uneven floors after primary tunneling. Manual trimming wastes time, while blasting is not allowed for secondary repair.

With high cutting accuracy, the tunnel miller finishes wall leveling, floor cleaning, edge trimming and roadway widening efficiently. It standardizes roadway profiles, reduces secondary support materials and cuts overall construction costs.

5. No-Blast Construction for Gas-Sensitive Coal Mines

Many underground coal mines ban blasting due to gas safety, ventilation requirements and surface protection limits. Blasting approval delays greatly affect project schedules.

The tunnel miller realizes full mechanical no-blast tunneling. It produces no explosion impact, low vibration and controllable dust. It supports 24-hour continuous construction and solves the bottleneck of restricted blasting operation.

Core Advantages for Soft Coal & Mixed Rock Conditions

• Adaptable to loose soft coal and uneven coal-rock mixed layers
• Precise roadway forming, less over-break and under-break
• Low vibration construction, lower roof collapse risks
• Continuous operation, stable daily tunneling output
  

  Front milling drum breaks rock, debris is conveyed out through onboard structure to realize continuous excavation and mucking

  

  Modular mining tracked mucking equipment with replaceable front working heads for conventional mucking and soft rock milling operations

  

  Integrated milling mucking machine executes hard rock cutting and muck conveying simultaneously

  

  Drum milling model for hard rock roadway tunneling and surrounding rock trimming & grooving