Subco Engineering delivered a fully engineered, rail‑mounted boat unloader system for PD Ports, designed to safely transfer a wide range of vessels from quayside to workshop. Through phased development, detailed load‑case modelling, adjustable trolley and cradle design, and a robust winch‑and‑sheave system, Subco created a flexible, future‑proof solution that enhances operational safety, efficiency, and reliability. The final system provides PD Ports with precise vessel handling, improved repeatability, and long‑term adaptability.

Subco Engineering partnered with PD Ports to design and deliver a robust, rail‑mounted boat unloader system capable of transporting vessels safely and efficiently from quayside to workshop. The project demanded deep technical insight, adaptable engineering, and close collaboration across multiple disciplines. The resulting system provides PD Ports with a highly configurable, future‑ready solution engineered for reliability and operational safety.
PD Ports required a system to move a range of vessels — from smaller boats to those up to 35–40 tonnes — from the water into a maintenance shed. The solution needed to:
Early assessments showed that critical loading assumptions (e.g., vessel weight readings) were sometimes inaccurate, meaning the engineering solution had to be robust enough to tolerate real‑world variability.
Subco Engineering delivered a phased design programme covering concept development, detailed engineering, and project close‑out. This structured approach ensured clarity, control, and adaptability throughout.
The first phase included:
This established a strong design foundation and enabled PD Ports’ civils teams to begin early planning with accurate data.
The next stage translated concepts into engineered systems with defined geometry, components, and interfaces. Key elements included:
Operational limits were clearly defined, including:
At project conclusion, Subco Engineering delivered a comprehensive package including:
The final close‑out documentation confirms the system comprises a rail‑mounted, dual‑trolley configuration with adjustable supports, moved by a paired winch system — purpose‑designed to reliably handle two main vessel classes with precision and safety.
The new boat unloader system provides PD Ports with:
Precise load distribution, modular cradle components, and controlled winch movement allow reliable vessel transfers independent of vessel type or hull shape.
Engineering controls and detailed O&M processes ensure teams can move vessels safely with consistent methodology.
The system’s wide range of adjustments enables PD Ports to support future vessels without major redesigns, protecting long‑term investment.
Subco Engineering’s detailed load cases, rigorous design checks, and structured project delivery provide clear traceability and confidence in system performance.
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