For many years, the heat transfer industry has used conventional plate-fin block for many applications which has proved to be an acceptable low-cost option. However, conventional plate-fin construction methods have inherent drawbacks and limitations which inhibit innovation and freedom of design.

During the early 1990's, work commenced on a new concept in extended surface technology. This patented process imparts certain unique advantages over conventional construction methods, enabling the heat exchanger manufacturer to gain technical superiority and excellence through innovation and choice.

During subsequent years, Elfin has evolved from a manually finned, single tube product to an infinitely versatile multi-tube, multi-row block which is now produced using state-of-the-art CNC controlled finning machinery. Patents and Patent Improvements have been applied for and/or granted in all appropriate regions including Europe, North and South America, Far East etc.

There is no other product on the market today that can match the versatility of Elfin at such an affordable cost. With successes in the marine, power generation, traction engine and chemical processing industries, we have only just begun to skim the surface of it’s capabilities.

What is Elfin?

The Elfin range of products, which is available in a wide variety of single-tube and multi-tube configurations, has been designed to offer outstanding levels of performance, durability and flexibility.

Elfin consists of individual fins which are swaged onto the tubes with great precision using the Patented ElfinMaster finning machine, with each fin having a positional accuracy of just a few microns. The fins, which can be 'collared' or 'collarless' (exposing the primary surface to the airflow), have holes formed to be a precise interference fit with the tube, the resultant mechanical bond negating the need for any further bonding method such as bullet-expansion or brazing. This process imparts a level of flexibility not generally associated with finned heat exchanger tubes.  Almost every aspect of the design can be optimised for the target application and environment.

Elfin is probably the best extended surface technology in the world. A bold statement indeed but consider the basic facts:

• Very few limitations of size and material
• Fin and tube shape can be customised
• Incorporates latest air manipulation technologies
• Integral flow manipulation
• Fins can be angled in relation to the tube in 3 dimensions
• Environmentally friendly
• No tube deformation
• Operating temperatures up to 300°C and beyond
• (Aluminum up to 200°C)
• Can be brazed for temperatures up to 800°C
• Fin pitches from 1 to 40 fins per inch are possible
• Allows ‘elastomeric’ tube to tubeplate seals
• Integral support mechanisms can be incorporated
• Tubes can incorporate internal extended surfaces

…Brazed Block:

• Brazing is not environmentally friendly
• Elfin can match or better brazed-block performance
• Brazing softens/weakens the tubes and fins
• Brazed block has more limited material combinations
• Block dimensions are limited by furnace size
• Expensive brazing and air purification equipment required

…Bullet-Expanded (‘Flexpanded’) Block:

• Tubes are deformed/stressed
• Expanding limits tube materials
• Expanding limits tube thickness
• Expanding inhibits the use of shaped tubes and internal profiles

Just imagine the possibilities...

Elfin technology is used by (to name but a few):

Atlas Copco Bergesen BOC Gases Europe CompAir Elliott Turbo Machinery First Hydro Electric Happag Lloyd

Hiross Magnox Electric P&O Nedlloyd Powergen Rolls Royce Nuclear RWE Innogy

Example louvre enhanced fin

Example internal tube profile

Example oval-tube fin

Example 4-row small tube core

Example 'crack & raise' enhanced fin

Example oval-tube marine core

Example vortex enhanced fin

Example custom fin

CFD analysis of vortex generator

CFD analysis of vortex generator

© Copyright 2004 Applied Cooling Technology Ltd. All rights reserved.
Elfin, ElfinBlock, IntegrElfin, ElfinMaster, Elfinesse, Convektor, VantageFin, JouleFlo, CrimpFin, CARFin, OvalBlock, Dri-Seal, Titan-Lite and Titan-Lite Max are Trademarks of Applied Cooling Technology Ltd.
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