Tube and shell heat exchangers are used to cool industrial processes ; when the cooling media is seawater or brackish water corrosion problems and biofouling can occur. Those production interruptions, planned or not, are often the source of high maintenance costs. Aluminium bronze alloys can be a solution to those issues, especially when linked to casting technology : NAB or aluminium bronze alloys have specifically been developped to face marine corrosion ( corrosion rate of approx. 0.05mm/year) and when used with sand casting lead to a higher thickness and no welding seams thus reducing the risk of leakage . The chemical composition of aluminium bronze, which is a copper based alloy including nickel, limits the growth of micro-organisms thus leading to less chemical treatments. NAB casting are a more reliable solution than coated steels as the protective film is not dammaged either by time or impacts .
Tube and Shell Heat exchangers are usual made of following components :
All those parts can be casted in our facility up to 4 m x 4 m for a total of 15 To poured metal . Calculations of those heat exchangers are usually made according ASME Code and therefore the most used aluminium bronze grades are ASTM B148 or B171 (with the possibility to switch to other standards such as EN 1982 or BS 14000). The various casted heat exchanger components are delivered worldwide fully machined and pressure tested with most of the time third party inspections by APAVE, Lloyds, Bureau Véritas, TUV… and usually also a required PED certification.
For specific military applications such as for submarines, design, calculation and manufacturing follows more stringent requirements due to high pressure levels due to depth , leading to the use of proprietary aluminium bronze alloys such as Inoxyda 154 or forging processes .