Custom Marine Box Coolers Tailored To Vessel Sea Chest & Cooling Needs

Custom marine box coolers (also called sea chest coolers) are compact, U‑tube bundle heat exchangers installed directly inside a vessel's sea chest (hull‑side seawater compartment). They provide reliable, energy‑free cooling by leveraging natural convection (at anchor) or forced flow (underway), eliminating the need for seawater pumps, filters, or complex external piping.

Core Design & Working Principle
U‑Tube Bundle Core: A corrosion‑resistant U‑tube bundle (CuNi 90/10, aluminum brass) forms the heat transfer surface. Hot fluid (engine jacket water, lube oil, hydraulic oil) circulates inside the tubes.

Sea Chest Integration: The bundle hangs inside the vessel's sea chest-a recessed hull compartment with inlet (bottom) and outlet (top) grids. Seawater flows freely over the tubes.

Dual Flow Modes:
Underway (Forced Convection): Vessel movement drives seawater through the sea chest, boosting cooling efficiency.
At Anchor (Natural Convection): Heated seawater rises, exits the top grid, and is replaced by cooler bottom water-no power required.
Closed‑Loop Safety: Process fluid (freshwater/oil) stays inside the tubes; seawater is outside. No risk of seawater contamination to engine systems.

Key Customization for Sea Chest & Vessel Needs
Each box cooler is engineered to fit your sea chest dimensions and heat load:
✅ Sea Chest Matching
Size & Geometry: Exact width/height/depth to fit existing or new sea chests; stepped designs for tight or irregular spaces.
Grid Positioning: Inlet/outlet grid alignment optimized for maximum seawater flow over the bundle.
Mounting Style: Top‑mounted (lowered into the sea chest frame), bottom‑mounted, or longitudinal/aft installation based on hull layout.
✅ Thermal Performance Tuning
Heat Load: Sized for 50–500+ kW to cool main engines, auxiliaries, thrusters, AC, or hydraulic systems.
Tube Material:
CuNi 90/10: Best corrosion & biofouling resistance (standard for seawater).
Aluminum Brass: Cost‑effective for moderate conditions.
Circuit Configuration: Single‑circuit (one heat source) or multi‑circuit (cool multiple systems with one unit).
✅ Marine‑Grade Construction
Tube Sheets: Naval brass or CuNi 90/10 for corrosion resistance.
Isolation & Protection: Fully isolated from the hull to prevent galvanic corrosion; optional WEKA Protector Type T or ICCP systems to suppress stray currents and marine growth.
Removable Bonnet: Allows tube bundle inspection/cleaning while the vessel is afloat.

Ideal Vessel Applications
Workboats: Tugboats, supply vessels (PSV/AHTS), dredgers, barges.
Commercial: Fishing vessels, ferries, general cargo ships, small tankers.
Specialized: Yachts, icebreakers, offshore support vessels.

Why Choose Custom Marine Box Coolers?
Standard coolers often force compromises between sea chest fit and cooling performance. A custom‑engineered box cooler delivers:
Perfect fit for your vessel's unique sea chest.
Optimal cooling for your exact heat load.
Lower operational costs and higher reliability.
Long‑term durability in harsh marine environments.