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Quotes - Engineering - SalesU-Tube Heat Exchangers For
304L and 316L Stainless
U-Tube Duty
304L and 316L are austenitic stainless steels with low carbon content, which reduces carbide precipitation at grain boundaries during welding and preserves corrosion resistance in the heat-affected zone. That is what the L means and it is why exchangers use the L grades.
Molybdenum. 316L contains roughly two to three percent, which markedly improves pitting and crevice corrosion resistance in chloride environments. That single addition is why 316L dominates hygienic, marine-adjacent and coastal service.
The limit. Chloride stress-corrosion cracking needs chlorides, temperature and tensile stress together. All three are present at a U-bend, which is why the bend region is where cracking initiates. Above roughly 140 degrees Fahrenheit with meaningful chloride, austenitic stainless becomes a risk and duplex becomes the sensible conversation.
Request a Quote304L and 316L Stainless Applications
Where 304L Is Enough
Closed loops of treated water, clean steam and condensate, and general utility duty with no chloride source are all comfortably within 304L's range, and the cost difference against 316L is real.
Where 316L earns its premium is anywhere chlorides appear: coastal cooling water, brine, food streams carrying salt, and any plant using chlorinated sanitizers. On product-contact sanitary duty 316L is effectively the default regardless.
Selection Data We Need
Flow rate and identity of both fluids, inlet and required outlet temperatures, operating and design pressures, allowable pressure drop on each side, and any code, alloy or hygienic requirement. Fouling history, turndown range and cleaning method matter as much as the design point.
