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Discover Our Leak-Proof, Long-Life Sealant

The EFC100 product line is a mature one consisting of a family of brushable and sprayable variants, sag-resistant fillets for high-stress zones, topcoats, quick-cure options and adhesion promoters.

1. History of EFC100

In the 1970’s, we launched our lightweight fuel bladders using a polyurethane technology. To date, we have supplied over 200,000 fuel bladders for a wide range of military and civil aircraft and many of the first installations are still in service.

We remain the only manufacturer to have perfected this technology.

EFC100 is based on the same polyurethane technology, available as a spray or brush sealant.

2. What is the chemistry behind the sealant?

EFC100 is a polyurethane-based sealant, rich in features that traditional coatings just can’€™t match.

EFC100 is a saturated polymer with no sulfur-sulfur bonds. These bonds, present in traditional coatings, are subject to ozone attack, typically resulting in cracking and splitting.

Benefits of EFC100 compared to traditional sealants include:

  • Retains its flexibility  – it does not dry out and crack
  • Leak proof – it does not yield under stresses
  • Superior adhesion  – it does not contaminate the fuel
  • No maintenance needed

3. What are the other benefits?

Where traditional sealants breathe, allowing oxygen to rise to their surfaces, EFC100 is non-porous and does not allow oxygen or water to reach the substrate. This means the likelihood of corrosion is almost entirely eliminated.

No passenger or crew is likely to be subjected to fuel vapors from an EFC100 coated integral fuel tank.

EFC100 is resistant to fungus, humidity, ultra-violet light and ozone.

Above all, there’€™s no danger of EFC100 degrading and contaminating fuel or being compromised by fuel additives.

EFC100 is self-levelling and remains effective even when applied more thinly than traditional coatings. These characteristics create a key feature: a level of translucency that allows for accurate
non-destructive testing (NDT) and visual detection of cracks in the aircraft structure.

Traditional sealants are opaque at any thickness, making NDT and visual inspection impossible.

4. Fatigue resistance of EFC100

Traditional sealants have low flexibility and limited life.

When EFC100 is fatigue-tested, it just doesn’€™t fail€“ despite millions of flex cycles at high amplitudes. To date, EFC100 has withstood at least two million flex cycles at a coating thickness of 0.010 inches.

Competing sealants fail easily. Even if they are applied four times thicker than EFC100, they fail at around 8,000 cycles. Traditional sealants require 25 times that thickness to achieve even 200,000.

That’s why EFC100 has been successful in addressing leaks arising from the high-stress points of integral fuel tanks in aircraft€“ where wing meets fuselage, for example.

And why EFC100 will be the only sealant to provide a functional  as well as cost-effective solution to sealing composite wings which flex more by far than any metal structure. Without EFC100, airlines can expect even higher maintenance costs than they have experienced to date with conventional coatings.

5. Maintenance and cost savings

Military customers have reaped the rewards of EFC100’s zero maintenance requirement.

E.g. On a military tanker, the cost of complete stripping and resealing with conventional sealant every five years, plus stripping and changing the topcoat every three, was eliminated.

30% weight savings

On this tanker, the EFC100 is 2,500 pounds lighter than a conventional sealant. At £25 per hour for every 500 extra pounds of weight, this equates to an annual saving of ~$55,000.

There is also the cost of unscheduled repairs, maintenance labour and facilities – or the cost of an aircraft that isn’t flying.

6. EFC100 for commercial aircraft

We are now able to turn our attention to realising the immense potential of EFC100in commercial aircraft to reduce airline maintenance costs.

We have started work with OEM partners who have seen the competitive advantage EFC100 brings to military applications.

EFC100 has been tried and tested over decades on military aircraft using manual spray and brush applications.

Now we’€™re on a timetable to deliver new mixing and dispensing methods including robotic delivery for commercial assembly lines.

7. Mathematics

Advantages of EFC100 compared to traditional sealants:

  • Millions of flex cycles at high amplitude
  • 10x stronger
  • 30% lighter
  • x2 elongation
  • 15 years’ total leak resistance (and counting)
  • ZERO maintenance

Link to the full brochure below

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