DOUBLE SHIELD TBM
Flexible Tunneling for Variable Geologies and Fracture Zones
The Double Shield TBM, offered by Sunward Machine, is the most versatile solution for hard rock projects characterized by rapidly changing geological conditions and fracture zones. This design features a telescopic shield that allows the machine to operate in two distinct modes: Gripper Mode (for high-speed tunneling in stable rock) and Shield Mode (for safe, continuous support in broken rock).
Mode 1: Gripper Mode (Stable Rock)
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Anchoring
Hydraulic Gripper shoes lock the inner shield against the rock wall. - 02
Parallel Thrust
Telescopic jacks push the cutterhead forward while the tail shield remains extended, allowing simultaneous segment erection during excavation.
Mode 2: Shield Mode (Fractured Rock)
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Support
The Telescopic Shield is fully retracted, providing full-circle ground support. - 02
Reaction Force
Excavation thrust is generated by pushing off the last installed segment ring.
Key Advantages (Adaptability and Speed)
Optimal Geological Versatility
Seamlessly transitions between Gripper Mode and Shield Mode, ideal for variable rock masses.
High Advance Rate (Parallel Erection)
Gripper Mode enables concurrent excavation and segment installation, maximizing throughput.
Ideal Applications
- ✓Long Tunnels with Alternating Rock Types
- ✓Projects crossing Seismic Fault Zones and Squeezing Rock
- ✓Mountain Tunnels requiring both speed and rock support.
Technical Structure
The core structural advantage is the Telescopic Shield—a design that allows the inner shield to extend and retract relative to the main shield, facilitating the two operating modes.
Key Components: Main Shield, Telescopic Shield, Main Thrust Jacks, Erection System.
Segment Erection: Segment rings are installed within the protection of the tail shield in both modes.
Interested in Flexible Hard Rock Tunneling Solutions?
Contact Sunward Machine today for customized TBM selection and project consulting.
