A Titanium marine heat exchanger is a cooling device (made from Titanium), that takes heat from a piece of machinery (diesel engine or air conditioning system), and carries the heat outside via sea water, to the ocean. This is identical to the way a radiator on a car moves heat from the engine to the surrounding air. Titanium is used because it is unaffected by the sea water and will last years longer than copper heat exchangers.
Titanium heat exchangers Titanium heat exchangers are advantageous to shipboard operations because they never fail due to corrosion or erosion, which is what happens with heat exchangers made with copper or stainless steel. Titanium is impervious to sea water attack and lasts decades in marine service.
Sea water is both corrosive and erosive, so copper and stainless-steel heat exchangers have a limited service life. Any heat exchanger that develops a leak can allow the machinery to become flooded with sea water with catastrophic results. Titanium is completely unaffected by sea water, lasting many years when properly maintained. Engines, A/C systems and hydraulic machinery are protected from collateral damage because the Titanium exchangers are so tough.
The best marine based heat exchangers are called “shell and tube” exchangers. These are best suited to handle debris, marine life, sand and silt. Shell and tube heat exchangers have large diameter tubes and do not easily plug or foul with marine life. Alternative “plate and frame” style heat exchangers are very prone to fouling and performance degradation because the plates are spaced very close together. Shell & tube exchangers are therefore the best solution for marine service.
1.) Shell & Tube
2.) Plate & Frame
3.) Tube in Tube
Shell & tube heat exchangers are comprised of many small diameter tubes “stuffed” into a single larger pipe. For example, 100 tubes of ½” diameter can be stuffed into an 8” pipe (called a shell). Cool sea water is circulated inside the tubes while hot water or gases are circulated outside the tubes, but inside the larger shell (pipe). The result is that the fluid inside the shell is cooled and the water inside the tubes is heated and passed overboard.
The advantages of a shell and tube exchanger when compared to a plate and frame unit are the tubes abilities to pass debris and marine life (crabs, shells, kelp and trash) through the cooling tubes. They are easy to clean, and they do not require expensive gaskets when disassembled for cleaning. Plate and frame exchangers are prone to decreasing water flow and heat transfer when the small water
passages become plugged.
Water is injected or sprayed into the engine exhaust when there is a need for a quiet and smoke-free exhaust. The sea water cools, muffles and knocks down the fumes normally associated with a ‘dry’ exhaust system. This technique is typically used on boats where the personal / passengers want to be free of any exposure to the exhaust fumes.
Wet exhaust systems are prone to corrosion due to acids in the hot exhaust streams when the components are made from stainless steel or copper. Titanium wet exhaust components last many times longer because they are unaffected by acid-based gases and the high 1,200 degree exhaust gas heat. Longer lasting Titanium exhaust systems cost less over the life of the vessel and prevent costly downtime.
The exhaust manifold is the hottest part of the exhaust system, at 1,000F temperature and is connected directly to the cylinder heads. By encasing the exhaust manifold in a water jacket, the engine room is kept much cooler because the water carries the heat away from the engine.
Gear boxes reduce the diesel engine rotational speed to a manageable level for the propeller. Typically, it may drop the revolutions from 1800 rpm to 150 rpm. In this process, the lubricating oil gets very hot and has to be cooled constantly. A gearbox cooler is a simple heat exchanger that removes heat from the oil and transfers it to the sea water. Oil is on one side of the tubes and sea water is on the inside of the tubes. Heat always travels from hot to cold, so the hot oil is cooled down by the sea water.
Maintaining a Gear Box Cooler is essential to preventing permanent damage to the gearbox machinery. If the cooler becomes ineffective due to plugging (by marine growth or entrained debris in the water) the oil temperature will climb until seals and bearings begin to fail and the gearbox is irreparably damaged; costing thousands of dollars and possibly months of downtime. Titanium based oil coolers are impervious to sea water and last many times longer than copper or stainless steel based coolers, thus protecting the gearbox.
Cost is directly proportional to the power of the diesel engine. Smaller engine – gear box combinations will be only a few thousand dollars while larger diesels will cost thousands of dollars more. With a properly sized Titanium gearbox cooler, the vessel is well protected from heat related damage.
Marine A/C systems are very similar to land-based systems except that they reject the heat to the ocean water instead of the air. Instead of a typical assembly of copper coils located outside the building, a marine A/C system has a shell and tube heat exchanger which cools the gas and rejects the heat to the sea water.
Marine A/C systems should last many years, if properly maintained. The weak link in any A/C system is the condition of the machinery: the compressors, heat exchangers, blowers and pumps. The component that fails most often is the condenser. If Titanium is used, the condenser is extremely resistant to corrosion and operational readiness will be significantly extended.
Refrigerated Sea Water (RSW) is used on fishing boats to quickly cool the catch by dumping the fish into large tanks of pre-chilled sea water at 30F. This quick cooling preserves the product quality and is also the first step if the catch is to be ultimately frozen using brine (rock salt added to the salt water).
They are the same.
Batteries give off heat when charging and discharging. This heat can damage the batteries and fires can start if the heat rises to a dangerous level. Battery cooling reduces the battery temps by removing heat with a cooling medium which is circulating around the batteries.
Treated water containing ethylene glycol is used in most cases although some systems use a thermal oil. Both operate in the same manner. Heat flows to the fluid and the fluid is then cooled by the sea water. Titanium based coolers are impervious to sea water and last many times longer than copper or stainless steel based coolers.
Cooling of the treated water or thermal oil by sea water are the two options used. Sea water cannot be used in direct contact with the battery system as it is full of salt, solids and marine growth. A two-step process involving a heat exchanger is always required. Due to the corrosive nature of sea water, Titanium heat exchangers offer many benefits over copper or stainless steel units.
