WEKA Boxcooler™

The go-to choice for naval architects and the marine industry worldwide when needing excellent protection from submerged obstacles.

R.W. Fernstrum & Company partners with WEKA Marine to manufacture copper-nickel boxcoolers in the United States, providing customers with a compact, closed circuit cooling system that is mounted in a sea chest within the confines of the vessel’s hull.

WEKA Boxcooler

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Design Features

90/10 Copper-Nickel

WEKA Boxcoolers are constructed using uncoated 90/10 copper-nickel tubing. Due to its inherent corrosion resistance to seawater and its natural anti-fouling capabilities, this alloy does not require a protective coating or ICAF (Impressed Current Anti-Fouling) system. A WEKA Guard and WEKA Protector Type T system is applied to protect the uncoated boxcoolers against potential stray current corrosion. This exclusive design is successfully utilized in hundreds of vessels in fresh and saltwater applications worldwide.

WEKA Protector Type T and WEKA Guard

Exclusive to WEKA Boxcoolers are the WEKA Guard and WEKA Protector Type T. This equipment helps minimize potential damage to the units and hull from stray electrical currents and galvanic corrosion. The WEKA Guard is used while the vessel is in the construction phase or when welding is being performed. The WEKA Protector Type T is used while the vessel is in operation. It allows the copper-nickel to maintain its natural anti-fouling capabilities, protecting the tubes from marine growth.

Isolation

WEKA Boxcoolers are constructed to be completely isolated from the hull during installation and in operation. Combined with the WEKA Protector Type T, isolation from the vessel’s hull allows the copper-nickel to maintain its natural anti-fouling properties.

Removable Bonnet

The bonnet can be removed from the boxcooler while the ship is still in the water.
Learn More About How Boxcoolers Work

Boxcooler Advantages

Closed circuit cooling system
  • Seawater does not enter the hull
  • Low maintenance solution
  • Eliminates inboard heat exchanger, raw water pumps, seacock, seawater piping, and strainers
  • Zero discharge solution: Eliminates potential contaminants entering seawater
Manufactured exclusively 90/10 Copper-Nickel tubes
  • ICAF system not required
Routine maintenance does not require dry docking
  • The exclusive bolt hole pattern allows the bonnet to be removed inside the vessel without sea water seeping into the vessel
Mounted inside a sea chest
  • Provides superior external damage protection
  • Promotes natural convection

Material Options

Premium materials to help maximize your cooling system
90/10 Copper-Nickel
Uncoated Tubes No ICAF System Required Made in USA
90/10 Copper-Nickel
WEKA Boxcoolers are constructed using uncoated 90/10 copper-nickel tubing. Due to its inherent corrosion resistance to seawater and its natural anti-fouling capabilities, this alloy does not require a protective coating or ICAF (Impressed Current Anti-Fouling) system. A WEKA Guard and WEKA Protector Type T system is applied to protect the uncoated boxcoolers against potential stray current corrosion. This exclusive design is successfully utilized in hundreds of vessels in fresh and saltwater applications worldwide. Request WEKA Boxcooler Quote

Configuration Options

Single or Multiple Heat Sources

A WEKA Boxcooler can be designed to support single or multiple heat sources with one unit.
Single Heat Source
Multiple Heat Sources

Stepped Boxcooler

A WEKA Boxcooler can be engineered to accommodate tight spaces by stepping the unit.

Installation Examples

There are several things to consider when determining the best installation option for a WEKA Boxcooler. These include operating conditions and hull design among others. Our expert engineers and sales team will help you determine the best installation solution for your vessel and application.

Athwartship
Longitudinal
A boxcooler is oriented one of two ways, athwartship or longitudinal
The sea chest requires careful planning, as inlet and outlet slots must provide a constant flow of seawater over the boxcooler’s tubes. Inlet slots are located at the base of the sea chest, positioned transversely to the outlet slots which are located on the side of the sea chest as near to the top as possible. The outlet slots must always remain below the waterline in all conditions, even when the vessel is in a light ballast condition. Refer to the installation manual for guidelines on slot quantity and sizing.
Bottom Mounted Boxcooler
WEKA Boxcoolers can be applied to bottom mount applications, such as repower projects or when additional equipment requires cooling. In most cases, a boxcooler is installed in a top-down fashion by lowering the unit into the mounting frame and securing the unit to the top of the sea chest. In a bottom mount application, a special top sea chest plate is pre-manufactured and secured to the unit’s mounting frame. The entire assembly is lifted from the bottom of the vessel through a hole cut in the hull and sea chest. The boxcooler is then fitted into the top of the sea chest and secured into place.

Documents

How Boxcoolers Work

The cooling water is circulated through the boxcooler tube bundle, which is suspended in the sea chest. Heat is transferred from the boxcooler tubes to the seawater. As the seawater is heated, it rises due to its lower density creating natural upward circulation. Openings in the bottom and upper side of the sea chest help to direct and focus the natural convection flow of seawater through the sea chest and across the boxcooler tubes. Additional cooling efficiency can be realized through forced circulation induced by the motion of the vessel.

Learn More About How Boxcoolers Work
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