
Marine Heat Exchangers
Marine heat exchangers prove to be cost-saving over time and add greatly to the resale value of the boat since they have a quality cooling system installed. The system works by drawing in the water the ship or boat is navigating through, or a coolant, and circulating it into the engine cooling system. Shell and tube heat exchangers or plate heat exchangers are common models used in marine applications. The process is similar for both exchangers: the cooling liquid absorbs heat from the engine and engine oil and transports it away, keeping the engine temperature at a moderate level and allowing for the engine oil to stay cool enough to lubricate the mechanism. Oil coolers are a vital part of a well maintained engine system. The heated water is then released through an exhaust system into the body of water.
Two types of water can be used: raw water or fresh water. Raw water is the water directly drawn into the engine. This can prove costly if using sea water as the salt content of the water over time corrodes the interior of the engine and leaves residue in the exhaust system. While it is a cheaper and simpler option in the short-term, using raw water in a marine heat exchanger will require the engine to be replaced eventually. Water conditions and rate of corrosion change depending on location and materials used, and therefore it is hard to predict how long it would take for an engine to deteriorate enough for replacement, and since engines are mostly hidden in boats and ships, it is hard to measure the damage. Another option for marine engine cooling is using fresh water, or a coolant in the system. This is more expensive to purchase and install, but will preserve the interior of the engine for a much longer time. Another advantage to a quality cooling system is during the winterizing process. This is necessary for preventing damage to a boat's engine during the cold winter months from freezing and compression or expansion. Ships also need to be properly engineered to prevent cooling system leakage and damage to the interior of the boat.