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Petrochemical
exchange surfaces against corrosion , accessibility of the heat transfer surface for cleaning , manufacturability of structure from the point of view of fabrication , and the economical use of costly materials . This final point requires the consideration of factors including : 1 . Fabrication characteristics – Stainless grades 310 and 310S rolled pipe , tube , plate / sheet in bent condition , and any forged component can be fabricated by cutting the products as designed , as these grades can withstand working temperatures in the range of 975- 1175 ° C . Heavy work is carried out down to 1050 ° C by standard methods and equipment .
2 . Machining – the machinability of grades 310 and 310S is similar to that of grades 304 and 316 . Work hardening can be a problem , and it is customary to remove the work-hardened layer using slow speeds and heavy cuts with sharp tools and good lubrication . Powerful machines and heavy , rigid tools are used .
3 . Weldability – Grade 310 / 310S products in any shape are a great way to connect two pieces of metal and have many advantages over other welding methods . Grade 310 is corrosion and heat-resistant , does not require a heat treatment step , and can be welded using various welding equipment . It is also ideal for projects that involve environmental protection and safety aspects . Stainless 310 / 310S grade is welded with matching electrodes and filler metals . Products are readily welded by standard welding manuals using techniques such as GMAW ( MIG ), GTAW ( TIG ) and SAW . Preheat and post-heat are not required , but post-weld solution
Nozzle inlet
Impingement plate
Tube bank
Figure 1 . Sectional view of a heat exchanger
annealing is essential for corrosion service in liquids . Pickling and passivation of the surface to remove hightemperature oxides are necessary to restore complete aqueous corrosion resistance after welding . This treatment is not required for high-temperature service , but welding slag should be thoroughly removed . Grades 310 / 310S are solution annealed by heating to 1040-1065 ° C , holding at temperature until thoroughly soaked , then water quenching .
Design and fabrication The primary function of heat exchangers in the petrochemical industry is solvent condensation undergoing chemical cooling and heating reactors . The design of the equipment is based on temperature ranges ,
30 Heat Exchanger World February 2024 www . heat-exchanger-world . com