To clarify: Plate HX's have a place. So to do Tubed HX' (and spiral tubes, etc., and even direct injection where you mix the fluids).
When building a new plant where you can specify adequate pre-filters plate HX's win out more often than tubed HX's except for condensation service and certain hazardous chemical environments. These modern plants almost always have closed cooling water systems where only 1 set of HX's are exposed to the base cooling water for the plant.
However, when dealing with an existing plant that was built with tubed heat exchangers it is often more economical to replace a HX with a tubed HX in a number of applications than change to a plate HX. Especially if they have raw surface water cooling piped all over the plant.
Tubed heat exchanger materials have evolved to where retubing or bundle replacement was a fairly routine activity (every 5-15 years) to now a rare activity (every 30 years too life of the plant: Admiralty Brass and plain copper has rarely had long life).
Designing HX's that do not have noticeable galvanic corrosion issues within themselves or on the adjacent piping for 40+ years is not simple: The old classic tube/tubesheet/baffle/shell alloys that worked for 100 years and did not cause galvanic corrosion to the adjacent piping are now rarely used. SS, the superferritic SS's, Titanium can cause the adjacent piping to have galvanic corrosion if not done right (especially if connected to carbon steel piping).
All HX materials are subject to other degradation factors other than chemical attack and may need NDE inspections for critical or hazardous applications to minimize to the lowest number possibility of leaks. In those cases tubed HX's often win out over plate HXs.
Do you prefer the metric system or the imperial system?
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To clarify: Plate HX's have a place. So to do Tubed HX' (and spiral tubes, etc., and even direct injection where you mix the fluids).
When building a new plant where you can specify adequate pre-filters plate HX's win out more often than tubed HX's except for condensation service and certain hazardous chemical environments. These modern plants almost always have closed cooling water systems where only 1 set of HX's are exposed to the base cooling water for the plant.
However, when dealing with an existing plant that was built with tubed heat exchangers it is often more economical to replace a HX with a tubed HX in a number of applications than change to a plate HX. Especially if they have raw surface water cooling piped all over the plant.
Tubed heat exchanger materials have evolved to where retubing or bundle replacement was a fairly routine activity (every 5-15 years) to now a rare activity (every 30 years too life of the plant: Admiralty Brass and plain copper has rarely had long life).
Designing HX's that do not have noticeable galvanic corrosion issues within themselves or on the adjacent piping for 40+ years is not simple: The old classic tube/tubesheet/baffle/shell alloys that worked for 100 years and did not cause galvanic corrosion to the adjacent piping are now rarely used. SS, the superferritic SS's, Titanium can cause the adjacent piping to have galvanic corrosion if not done right (especially if connected to carbon steel piping).
All HX materials are subject to other degradation factors other than chemical attack and may need NDE inspections for critical or hazardous applications to minimize to the lowest number possibility of leaks. In those cases tubed HX's often win out over plate HXs.
I wish you the best...