High pressure cylinders for motor vehicles that use Compressed Natural Gas (CNG) for their propulsion can now benefit from zero permeation, cost competitive, lightweight advanced materials.
Thanks to the unique combination of an inner liner made with Akulon® Fuel Lock from DSM and the superior mechanical characteristics of HiPer-tex™ high performance glass fibre from 3B, Gastank Sweden AB, is now able to produce zero permeation cylinders that meet the very stringent ECE R110 regulation governing the use of Type IV high pressure CNG cylinders for motor vehicles.
Akulon Fuel Lock, based on high performance Akulon PA6, reduces evaporative emissions from engine fuel tanks by more than 99 percent, far exceeding EPA regulations. With grades for both injection and blow molding, this durable material facilitates the production of thin-wall designs, saving costs and improving productivity.
Professor Kurt Berglund, President Gastank Sweden AB stated: “The combination of both Akulon Fuel Lock and HiPer-tex glass fibre enables optimizing the cost-benefit ratio of Type IV cylinders. HiPer-tex high performance fibres bridge the gap between heavy weight steel and high cost carbon fibre composites due to its ability to deliver a comprehensive range of properties economically whereas the newly developed cost effective Akulon Fuel Lock considerably reduces loss of gas through permeation.”
Berglund goes on to say: “Well recognized independent consulting Powertech Labs Inc. Canada did not detect any loss of gas via permeation in our newly developed Gastank™ 32, CNG tank with 32 litre capacity. This unprecedented result makes our lightweight, zero permeation composite CNG tanks a benchmark within the composite cylinder manufacturing industry.”
Eric Debondue, Business Development Leader at 3B added: “3B’s unique HiPer-tex glass formulation delivers a high level of performance in composite parts such as windblades, ballistic armour and high pressure vessels or pipes while ensuring sustainable economics. We are very proud at 3B to partner with Gastank Sweden AB and DSM to develop an extremely reliable and durable CNG tank thanks to the high mechanical, fatigue and corrosion resistant properties of HiPer-tex fibre as well as the unique high barrier properties of Akulon Fuel Lock.”
Tim Vorage, Application Development Manager at DSM, adds: ”Our newly developed cost effective Akulon Fuel Lock not only shows a permeation factor at least 150 times lower than high density polyethelyne (HDPE), it also significantly limits creep under extreme temperatures at the cylinder’s neck thanks to a 50°C higher temperature resistance than HDPE. In addition, the ability to withstand higher temperatures allows a faster curing time of the composite material.”
CNG fuel systems equip approximately 2 million cars every year with as many as 4 tanks installed per vehicle. Some OEM’s offer CNG as an option, however many vehicles are retro-fitted and the use of CNG is expected to grow at 18% per year.