Dispersed Fibre Technology
Specialist Materials Dispersed Fibre Technology
Metflex DFT™ – Dispersed Fibre Technology delivers the following key benefits:
- Improved Ozone Resistance
- Three Dimensional Shaped Moulding Capabilities
- Improved Flex and Durability
- Elimination of “Wicking”
- Environmentally Friendly Production Process.
A major product development by Metflex resulted in the trademarked Dispersed Fibre technology or DFT, which is now universally accepted for moulding usage in regulators and diaphragms.
This technology utilises fibers being dispersed through the polymer rather than the insertion of fabric into the polymer.
Steve Parry, Director of Development at Metflex Precision Mouldings Ltd identified the two dimensional limitations of traditional coated fabrics and set about identifying a polymer / fibre combination, which would give increased benefits including the ability to manufacture three dimensional products in a one shot moulding process.
A number of potential customers were identified to ensure the development resolved the limitations which Steve had identified and importantly to resolve any technical issues the customers faced. It became clear the majority faced a number of common limitations with the available coated fabrics, which were used in a number of products for example diaphragms. The problems faced with the existing technology were largely the stretch of the material, together with weaknesses caused by the interaction between the polymer and the inserted fabric (typically polyester, nylon or cotton). In certain applications the product is in constant use for a minimum period of 20 years as this life expectancy forms part of the overall product guarantee.
This variability, previously mentioned, resulted in potential warranty claims, customers were becoming increasingly concerned with their current suppliers’ ability to provide a reliable moulded solution. However, at this time DFT was in its development and Steve discussed his findings with a number of potential customers.
Steve and his team, once the formulation was proven, set about an extensive period of testing, which was six months at both potential customers’ sites and also within the Metflex testing facility, these tests were independently verified and proved that DFT significantly exceeded the design specification.
It was clear that DFT addressed the issues the customers faced, Dispersed Fiber Technology also addressed the problems of “wicking”, which is the transfer of a media through the fibre chain – the construction of DFT means it does not have a potential leak path and therefore no passage of a medium is possible through it.
This is an additional benefit not originally expected during the development stage, but was identified during product testing in different applications by several customers.
Also, various other demanding tests were carried out, one of which was to ensure the product would withstand a minimum requirement of half a million “flexes”, which is the equivalent of the 20 year life expectancy referred to previously.
The flex testing showed that the currently sourced material at the time was achieving between fifty to one hundred thousand “flexes”, which explained the number of failures. DFT, when tested, proved the material could withstand over three million “flexes” at this point the Metflex testing ceased as the customer was delighted at the substantial improvement and placed tooling and product orders. However, they were interested to know at what point DFT would fail the flex test and they continued with their own testing. To date DFT has still not failed, despite achieving over 12 million cycles.
To date over 15 million components have been produced using DFT, not only with Nitrile (NBR / Buna –N), but now with Ethylene Propylene Diene Monomer (EPDM), Fluorocarbon (FKM), Epichlorohydrin (ECO). Also, under development are DFT versions of Fluoro Silicone (FVMQ) and Silicone (MQ). The key points to the success of DFT are the processes used by Metflex within the production department, the strict adherence to its own quality processes, and the rigorous attention to detail throughout the total process ensures that DFT is able to be moulded into very complex three dimensional products with the possibility to continuously achieve or exceed the normal industry tolerances required. In fact DFT can be consistently manufactured to a thickness of 0.2 mm – this ability to produce such a thin section in a reinforced product is a major testimony to the continued success of DFT.
In summary, here are a few significant benefits that DFT can offer:
- Improved ozone resistance, one of the disadvantages of rubber is that it cracks over a period of time, this is not the case with DFT due to the dispersion of the fibres, which gives both strength and resistance to ozone attack.
- Three dimensional shaped mouldings rather than the traditional two dimensional with conventional rubber coated fabric formulations.
- Improved flex and durability due to the fibre dispersion and also the formulation developed by Metflex.
- Elimination of wicking along the fabric path.
- Environmentally friendly production process, which is achieved by not using solvents in the manufacture of DFT products. This is not the case in some processes, when producing conventional fabric reinforced products.
For more information on what benefits DFT could offer your business please contact Metflex.