Exceptional Clamping & Crushing Force
The barrel is made from high yield-ratio quenched & tempered alloy steel thick-wall tube. The piston rod is a heavy-wall rod or solid forging with hard chrome plating (HV900–1100). Welds undergo UT and MT inspection with stress relief, enabling the cylinder to withstand strong pulsating side loads and rock reaction forces. Fatigue life exceeds 800,000 clamp/crush cycles.
Specialized Composite Sealing & Water Exclusion System
To cope with high‑clay, highly abrasive slurry conditions, a “polyurethane + filled PTFE” primary seal package is paired with hydrolysis‑resistant O‑rings. A high‑pressure flushing port and drainage chamber at the front of the guide bushing prevent muck ingress into the hydraulic fluid and sealing faces, ensuring long‑term zero leakage.
Integrated Hydraulic Lock for Safety
Standard dual pilot-operated check valve or counterbalance valve ensures the crusher jaws remain clamped even if a hydraulic hose breaks during boring, preventing oversize rocks from suddenly entering the discharge port and causing system blockage.
Ultra-Low Breakaway for Precise Gripping
Low‑friction seals and precision guide rings keep breakaway pressure ≤0.35 MPa, allowing fine jaw adjustment and easy adaptation of clamping force for different rock sizes, reducing excess wear and energy consumption.
Full-Spectrum Anti-Corrosion
External surfaces are coated with slurry‑resistant epoxy. The piston rod is available with hard chrome, Ni/Cr plating, laser cladding, or ceramic thermal spray. Bottom and gland fasteners are stainless steel — ideal for the long‑term water‑immersed front chamber of a shield machine.
Smart Sensing Interface
A built-in linear displacement sensor can monitor jaw opening, or a pressure sensor can be integrated to detect clamping force, linking to the shield control system for automatic crushing control and anti‑blockage warning. Position accuracy ±0.3 mm.
Maintenance-Free Pivot Points & Compact Mounting
Standard self‑lubricating composite bushings in the clevises eliminate grease fittings and provide long wear life in tight spaces. Mounting dimensions and port orientations can be customized to fit the cutter drive housing or bulkhead of any shield brand.
