A finned tube heat exchanger puts one medium inside the tubes and passes the other across the outside. Fins multiply the gas-side surface, which is the most effective way to raise overall heat transfer when the gas-side coefficient is low.
Core design questions
- Which tube material suits the medium and pressure?
- Which fin material balances heat transfer, corrosion and cost?
- Which fin process gives the required contact and temperature capability?
- What fin spacing keeps the passage open in a dusty stream?
Fin processes
Wound fins are a general-purpose choice. Sleeve-on fins allow the fin material to differ from the tube. Embedded fins resist vibration. Integral rolled fins have no contact resistance. High-frequency welded fins tolerate high temperature and thermal cycling. Brazed fins give low contact resistance and a compact bundle.
Why custom design matters
The available envelope, duct connection and cleaning access often matter as much as the thermal calculation. A coil that cannot be installed or cleaned will not perform over its service life.
Mazelu builds finned tube exchangers for air heating, air cooling, flue gas cooling and heat recovery.