EN10217-7 1.4301 Extruded Finned Tube With Al1060 Fins for Waste Heat Recovery Units

EN10217-7 1.4301 Extruded Finned Tube With Al1060 Fins for Waste Heat Recovery Units

1. Product Overview

Our EN10217-7 1.4301 Extruded Finned Tube with Al1060 Fins is a premium bimetallic heat transfer component engineered for reliable, long-run industrial thermal exchange. It combines pressure-resistant stainless steel core tubing and high-conductivity pure aluminum fins through cold extrusion rolling technology, eliminating loose contact gaps that commonly trouble wrapped or embedded fin tubes.

The inner pressure-bearing base tube is manufactured strictly to EN 10217-7, the European standard for welded stainless steel pressure tubes, material grade 1.4301 (AISI 304). This base delivers good mechanical strength and general corrosion resistance for pressurised process media such as hot water, steam and mild chemical fluids flowing inside the tube.

Outer spiral fins are cold-extruded from Al1060 commercially pure aluminum sleeve. Thanks to aluminum’s outstanding thermal conductivity, heat transfers rapidly from the steel substrate out to air-side flow. Under high-pressure rolling, fins and aluminum base form one integrated body, tightly wrapped around the stainless steel core tube. This special structure also covers and shields the outer steel surface from atmospheric and coastal-environment corrosion, extending overall service life.

Different from embedded fin tube (G-type) or L-foot wrapped fin tube, extruded fin construction keeps minimal thermal contact resistance even after repeated thermal cycling, preventing efficiency drop caused by fin loosening over operation time.

2. Base Tube: EN 10217‑7 1.4301 (AISI 304) Welded Tube

(1). Chemical Composition (%, max unless range)

Remarks: EN 10217-7, material 1.4301; MTC issued per EN 10204 3.1

(2). Mechanical Properties (Room Temperature, solution-annealed condition)

3. The Advantages of Combining EN10217-7 1.4301 Welded Base Tubes with Al1060 Extruded Aluminum Fins

• Reliable pressure resistance from EN10217-7 1.4301 base tube EN10217-7 is the European standard for welded pressure-bearing stainless steel tubes. Grade 1.4301 delivers good tensile strength and proof stress under operating pressure. The welded seam is 100% eddy-current tested, making the base tube safe to carry pressurised steam, hot water and process fluid inside the tube. It provides satisfactory general corrosion resistance against many medium-aggressive process media, which pure aluminium cannot achieve on its own.
• Superior air-side heat transfer performance of Al1060 pure aluminium fins Al1060 is commercially pure aluminium with high thermal conductivity. Compared with steel fins, aluminium transfers heat far more efficiently to the surrounding air flow. For air-cooler and waste-heat-recovery working conditions, Al1060 fins greatly enlarge the heat-exchange surface and boost overall heat dissipation efficiency. The material also has good ductility, which is critical for the extruded fin manufacturing process to form uniform, intact spiral fins without cracking.
• Metallically tight tube-fin bonding minimises contact thermal resistance During the extruded fin production process, the Al1060 aluminium sleeve is cold-rolled and extruded onto the outer surface of the 1.4301 stainless steel tube. This mechanical interlocking eliminates gaps between fins and the base tube. Unlike L-type wrapped fins or manually embedded fins, this combination maintains low contact thermal resistance even after repeated heating-cooling thermal cycles. Heat loss at the joint interface is kept to a minimum, and heat-exchange efficiency will not degrade over long-term operation.
• Outer aluminium layer provides extra surface protection for stainless steel substrate The extruded Al1060 fin base fully covers the outer wall of the 1.4301 steel tube. The stainless steel core is shielded from direct exposure to humid air, dust and coastal saltspray atmosphere. It reduces the risk of outer-surface oxidation and atmospheric corrosion of the steel base tube, therefore extending the whole service life of the heat-exchanger tube bundle.
• Cost-effective balance between corrosion resistance and thermal performance Using full stainless steel fins would significantly raise material cost, while carbon steel fins suffer fast atmospheric rusting. This material combination avoids both downsides: the expensive stainless steel is only used for the pressure-wetted inner core to handle process media, and low-cost high-conductivity Al1060 handles the air-side heat transfer. It delivers targeted performance without unnecessary overspecification.
• Good manufacturing flexibility and stable dimensional consistency EN10217-7 1.4301 welded tubes are available in a wide range of outer diameters and wall thickness. Soft, ductile Al1060 can be extruded into various fin heights and FPI (fins per inch). Engineers can configure custom fin parameters according to heat-duty requirements, to match different air cooler, heater and waste-heat recovery unit designs.

4. Typical Applications

This extruded fin tube solution is widely adopted across multiple industrial sectors:

• Air coolers & forceddraft air heaters
• Waste heat recovery units, fluegas heat recovery systems
• Process heat exchangers for chemical, foodprocessing plants
• HVAC industrial heating & cooling equipment
• Power plant auxiliary heatexchange assemblies
• Coastal site installations where atmospheric corrosion needs mitigation