Main Operating Cylinder

Bore diameter: Φ100mm – Φ400mm

Rod diameter: Φ50mm – Φ180mm

Stroke: ≤7,300mm (multi-stage telescopic, customized to ramp length)

Operating pressure: continuous 21MPa, max 28MPa

Max push force: 3,500 kN (at 28MPa, Φ400mm bore)

Max pull force: adequate retraction force to overcome ramp self-weight, depending on stage count and rod size

Breakaway pressure: ≤0.5 MPa

Piston velocity: 0.02 – 0.2 m/s (smooth deployment)

Operating frequency: 1–2 full cycles per port call, up to dozens of cycles daily

Internal leakage: ≤0.03 ml/min (at 21MPa, over seal service life)

Static holding: ≤2 mm piston drift over 24 hours under full locking load (with counterbalance valve)

Temperature range: -20℃ to +80℃ (standard); -40℃ to +100℃ customizable

Suitable vessels: Ro-Pax ferries, Ro-Ro cargo ships, PCTC, train ferries

Massive Thrust & Ultra-Long Stroke

The single-stage plunger or multi-stage telescopic configuration overcomes hull mounting constraints to smoothly lower the heavy-duty ramp. Large-diameter, thick-walled alloy steel piston rods and high-yield alloy cylinder barrels provide exceptional rigidity under full load, eliminating any buckling or deflection.

Integrated Counterbalance Valve & Safety Locking

A high-flow counterbalance valve allows the cylinder to lock the ramp at any intermediate angle instantly. Even in the event of a hydraulic system failure during loading, the ramp's position will not shift, ensuring absolute safety for vehicle traffic and dock personnel.

Built-in End-of-Stroke Cushioning

An integrated progressive cushioning mechanism at both ends automatically decelerates and absorbs energy when the ramp fully contacts the dock or returns to the stowed position. This protects the hull hinge points, ramp structure, and the cylinder itself from rigid mechanical impact.

Multi-Layer Anti-Corrosion & Seawater Resistance

To withstand the splash zone, salt spray, and high humidity, the piston rod surface can be laser-clad with a nickel-based alloy or ceramic-coated. The exterior is finished with a marine-grade heavy-duty coating system. All external fasteners are stainless steel, withstanding over 6,000 hours of neutral salt spray testing.

Intelligent Position Monitoring

External draw-wire or built-in magnetostrictive displacement sensors (±0.5mm accuracy) provide real-time ramp angle feedback. This integrates seamlessly with the ship's bridge control system for one-touch deployment and status display.

Complete Certification & Maintenance-Free Pivots

Type approval from major classification societies such as CCS, ABS, and DNV is available. The pivot points are equipped with standard self-lubricating composite bushings, eliminating the need for grease and ensuring minimal wear under high load and frequent pivoting.

Multi-stage telescopic stroke customization

Full stainless steel body and piston rod

Internal/external displacement sensor

CCS / DNV / ABS / BV type approval

Polar low-temperature design

Anti-fouling coating