As a core heat exchange component in industrial thermal systems, finned tubes significantly improve heat transfer area and overall heat exchange efficiency through the addition of extended spiral fins on the surface. Today, whether manufactured as integrally rolled finned tubes or high-frequency resistance welded (HFRW) spiral finned tubes, these products are widely utilized in various industrial boilers and air conditioning systems.

However, under extreme cold working conditions, the equipment faces severe temperature challenges. Preventing the temperature of the heat exchanger from dropping too low—which leads to the freezing and cracking of finned tubes—is critical for ensuring stable system operation. Below are the primary causes of freeze damage and engineering solutions to prevent it.

• Excessive Margin in Heat Exchange Area: During system design, if an excessively large redundant margin is left for the finned tube's heat exchange area, it results in a low flow velocity of the heat medium (hot water or steam) during winter operation. Once the flow velocity drops below the safe critical threshold, the fresh air side coil is highly susceptible to icing. The expansion stress from the ice ultimately causes the finned tubes to freeze and rupture.
• Improper Piping Installation: If piping is improperly handled during the installation process—such as incorrect grading or lack of effective drainage design—water will accumulate at the low points of the system. During shutdown or ultra-low temperature conditions, this stagnant water rapidly freezes, thereby destroying the base tube and spiral fin structure.

• Accurately Control Heat Exchange Area Margins: When conducting thermodynamic calculations, the heat exchange area must be strictly evaluated based on actual working conditions, avoiding blindly leaving excessive margins. Ensure that the heat medium maintains its designed flow velocity even under extreme winter conditions to prevent internal stagnation and freezing.
• Optimize Coil System Layout: Logical spatial arrangement is a physical safeguard against freezing. If the system involves a remote heating zone, the air cooler (cooling coil) should be placed after the air heater. By pre-heating the incoming air, you can effectively prevent the downstream cooling coils from freezing due to excessively low windward temperatures.
• Install Independent Air Heating Modules: When the heating area requirement is smaller than the cooling area requirement, compromising the design is not recommended. Instead, an independent air heater should be installed separately. This not only completely eliminates the hidden danger of freezing caused by localized overcooling but also avoids energy waste, thereby enhancing the reliability of the system.

Beyond system design, strict routine inspections must be executed during the product's frequent usage cycles. Focus on verifying the smooth operation of drain valves at the low points of the piping. Concurrently, high-frequency resistance welded finned tubes with high welding density and strong base-tube bonding should be prioritized during procurement to enhance the component's inherent thermal fatigue resistance against extreme temperature fluctuations.