Aluminum L-Foot Finned Tubes

Vulcan’s Aluminum L-Foot Finned Tubes consist of thin aluminum fin strip tightly wound helically around the tube circumference. An L-shaped foot, 1/16″ wide, is first formed on one side of the fin strip (hence the name L-Foot). The strip is then wound tightly around the tube, with the foot bearing on the tube outer surface. A typical fin spacing is 10 fins per inch of tube length — this can be varied. Tension in the fin strip as it is wrapped around the tube serves to seat the fin foot forcefully on the tube, and to hold the fin firmly in place.

The following table shows common Aluminum L-Foot Finned Tube configurations:

 Tube OD 5/8”, 3/4”, 1”, 1-1/4” and 1-1/2″
 Fin Height 3/8″, 7/16”, 1/2” and 5/8″
Fin Type Solid or Perforated
 Fin Thickness 0.014” to 0.016″
Number of fins 8 to 12 fin per inch
 Fin Material Aluminum 1100-0 or Aluminum 5005
 Tube Material Generally carbon steel, stainless steel, or brass — can be any material
 Tube Length No practical limit

* This table should be used as a general guide to our capabilities for Aluminum L-foot Finned Tubes. Grade of material, tube outside diameter to fin height and other factors may limit these capabilities. Please call us for guidance when designing your next finned tube.

Vulcan also has the added capability of manufacturing Perforated L-foot Finned Tubes (sometimes referred to as wheel fin), which is identical in configuration to the regular L-foot fin, except that holes are perforated through the fins at regularly spaced radial intervals. Significant heat transfer advantages have been claimed for perforated L-foot finned tubes in air coolers, under the premise that interruptions in the fin surface reduce the thickness of the stagnant air film that builds up on the fin as air flows over it. This reduced film thickness results in an increased film coefficient, thereby increasing overall heat transfer rate.  The improved heat transfer efficiency can reduce heat transfer surface area requirements and cooler size, or reduce airflow and fan horsepower requirements.

Aluminum L-Foot Finned Tubes are typically used in low temperature applications not exceeding 350 degrees F. They are primarily used in air-cooled applications such as large radiators, compressor oil coolers, and other forced-draft or induced-draft air-cooled applications.

To learn more about this product see Vulcan’s Standard Specifications for Aluminum L-Foot Finned Tubes.