Marine Heat Exchanger Guide: Central Cooling, Engine Cooling and Auxiliary Duties
Titanium plate and shell-and-tube heat exchangers for shipboard central cooling, engine jacket water, lube oil and fuel conditioning — selection, materials and class-society requirements.
Why ships rely on heat exchangers
A modern vessel runs dozens of heat exchangers — central freshwater cooling against seawater, main engine jacket water, lube oil coolers, fuel oil heaters, charge air aftercoolers, hydraulic oil coolers, refrigeration condensers and HVAC chillers. Reliability, compact footprint and resistance to seawater corrosion drive every selection decision.
Central cooling — the heart of the system
Modern vessels use a central freshwater loop that absorbs heat from every onboard consumer and rejects it to seawater through a central cooler — almost always a titanium plate heat exchanger. The plate construction offers high efficiency at low weight, compact footprint in cramped engine rooms, and easy bundle access. Titanium is mandatory: stainless 316L corrodes in seawater within months.
Engine and lube oil cooling
Main engine jacket water is cooled against the central freshwater loop in a dedicated plate or tubular cooler. Lube oil cooling demands robust shell-and-tube or compact welded plate units sized for the heat rejection of the prime mover. Charge air aftercoolers (for two-stroke and four-stroke engines) typically use finned-tube bundles cooled by central freshwater.
Material standards and class society approval
Class societies — Lloyd's Register, ABS, DNV, BV, CCS, NK — require approved drawings, material certificates (typically EN 10204 3.1 / 3.2), pressure test records and witnessed testing on safety-critical exchangers. Plate material is almost always titanium for seawater-wetted surfaces; gasket compound is typically NBR or EPDM for engine cooling and Viton for fuel oil. Frame and connection material follow the marine specification.
Retrofit and aftermarket
Most marine plate heat exchangers are eventually retrofitted with replacement plate packs and gaskets rather than complete unit replacement, because the original frame, piping and foundation remain serviceable. Compatible plate packs and gaskets for common Alfa Laval, Sondex, GEA and APV marine models are widely available and reduce cost and lead time over OEM replacements.
Aquaculture and offshore
Beyond shipping, the same titanium plate technology serves recirculating aquaculture systems (RAS), offshore production platforms (HVAC, cooling water, glycol regen) and floating LNG. Each application has specific design pressure, motion and inspection requirements that should be specified at the inquiry stage.
Jiangxing manufactures marine-grade heat exchangers
Shanghai Jiangxing manufactures titanium plate, welded plate and shell-and-tube heat exchangers for marine central cooling, engine cooling and auxiliary duties — built to class society requirements with full material and test documentation. Send the heat duty, seawater temperature, primary loop conditions and class society and we will return an engineered selection within one to two business days. Evan, jxmike@shheatex.com, WhatsApp +86 173 1725 8304.
Send your working conditions to Evan
Share your medium, temperatures, flow rate and pressure — Evan will return a thermal selection and indicative pricing after reviewing the available data.