From the ground up…
In the ground support segment of Outdoor Power Equipment the challenge is clear: Unlike traditional automobiles which now tend to emit very little in the way of evaporative emissions, the small power-hungry engines used in mowers and other ground support equipment need to comply with the US Environmental Protection Agency (EPA) which has set the global standard.
This standard limits the quantity of hydrocarbon permeation allowed to pass through the wall of a small engine fuel tank to 1.5 grams per square meter of internal tank area per day at 28°C; or 2.5 grams per square meter per day at 40°C.
As gasoline (petrol) becomes more scarce and expensive, the trend towards fuel made from renewable sources (corn) will drive even tighter performance requirements for fuel engines – all of which we are well placed to meet with our Akulon® Fuel Lock solution.
Rethinking the fuel tank
But we are not just able to provide the next-generation materials to meet this next-generation need. We can also bring our design experience to bear in helping to redesign and re-imagine the fuel tank – which means creating a component that’s more efficient to produce – for example through the ability to use three types of molding techniques (blow/injection/rotational) all with one family of materials.
Ground support isn’t just about emissions. We see a growing trend for materials that can stand up to harsh conditions over time including resistance to chemicals like oil and fuel; and that have excellent surface appearance that enable brands to look their brightest and best.
Increasingly, our plastics can fill this role.
Improved engine performance is another key issue. More power means more heat. But thanks to outstanding heat resistance, our materials are increasingly used for materials both in and around the engine.
Systems Go: How to make it work?
The benefits of polyamide (nylon) 6 fuel tank are hard to resist but we realize that switching materials is a big decision. The truth is that you can drop Akulon® Fuel Lock into your existing manufacturing process with very little extra work needed. DSM’s Mark Schireson Explains how…
So, how easy is it to move from HDPE to Akulon Fuel Lock?
With mold shrink values that overlap those of HDPE, Akulon Fuel Lock compounds have been successfully molded using injection molds, blow molding equipment, and hot plate and vibration welding equipment that were originally used for HDPE, eliminating the time and cost associated with re-tooling your operation.
How is Akulon Fuel Lock less expensive than HDPE?
Despite its durability and the fact its reduces evaporative emissions over 99% compared to HDPE, it’s equivalent in cost to most other permeation control technologies, and less expensive than post-processing treatments like fluorination and multi-layer co-extrusion, and doesn’t need any press-side additives or additional post-processing. It’s ready to use out of the box, creating fuel tanks in one process without the cost and logistical planning needed to ship tanks to a separate location for additional treatments.
How does Akulon Fuel Tank make compliance easier?
Once the process of making fuel tanks from the Akulon Fuel Lock is certified to applicable EPA and CARB standards, that’s it. The quality and extremely low permeation rates are guaranteed from there across all tanks produced from the material because the barrier performance is inherent in the plastic rather than batch dependent (like fluorinated HDPE).
What are the processing benefits?
Well, because it’s a polyamide-based material, Akulon Fuel Lock is stronger, more durable and highly permeation resistant than HDPE, which means we can redesign the fuel tank with significantly thinner walls which means using less material. But we can also reduce cycle time thanks to Akulon Fuel Lock’s faster recrystallization rate from the melt. The use of regrind Fuel Lock, from blow molding “lay-flat” and other scrap, may be used at very high levels without affecting processability, permeation characteristics or mechanical properties.
What testing have you conducted on Akulon Fuel Lock at DSM?
Fuel Lock is exceptionally resistant to chemical attack and extraction by all fuels and biofuels currently used or even considered for use in the future for fuel tanks. Our technical team has conducted exhaustive laboratory tests and subsequent validation, which shows that the use of ethanol as a significant bio-extender in gasoline doesn’t significantly affect permeation rates – or indeed impact strength.