James Walker invests in UK sales strategy to meet customer growth
- Publisher
- Elsevier Science
- Year
- 2011
- Tongue
- English
- Weight
- 85 KB
- Volume
- 2011
- Category
- Article
- ISSN
- 1350-4789
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✦ Synopsis
Elastomers, Metals and Sealants' it was prepared under contract by ORNL for the US Department of Energy (DOE).
Material selection was based on a thorough investigation of dispenser materials by the ORNL materials research team. Team members contacted dispenser component and elastomer/seal manufacturers and received input from stakeholders including Underwriters Laboratories (UL), the Petroleum Equipment Institute (PEI) and American Petroleum Institute (API) members. Although the research team was able to identify typical dispenser materials (especially elastomers) according to class, specific grades and formulations could not be precisely identified.
In this study, four test fuels based on the Fuel C composition, and aggressive ethanol were examined. These formulations are based on test fuels described in the Society of Automotive Engineers' SAE J1681, 'Gasoline, Alcohol, and Diesel Fuel Surrogates for Materials Testing'. The fuel types studied were Fuel C, CE10a, CE17a and CE25a. Fuel C is a 50-50 mixture of toluene and isooctane and is representative of highly aromatic gasoline (greater than 40% aromatics by volume). The other test fuels contain an aggressive ethanol solution added to Fuel C -hence, the CE nomenclature.
The elastomer classes that were selected for study were fluorocarbon, fluorosilicone, silicone, acrylonitrile butadiene rubber (also known as nitrile rubber or NBR), styrene butadiene rubber (SBR), polyurethane and neoprene. The test matrix included eight types of fluorocarbons and six grades of NBR, while the remaining elastomer types consisted of one sample only.
The elastomers, placed in the liquid phase region, were evaluated for volume, mass and hardness changes for both wetted and dried conditions. Dynamic mechanic analysis (DMA) was performed on each specimen to assess elasticity over a wide temperature range.
Three specimens were exposed to the liquid phase, while one specimen was exposed to the vapour-only regions. The metal and elastomer coupons were loaded into stir chambers which were held at 60°C for four weeks while being subjected to a constant flow of 0.8 m/s.
Pipe thread sealants were introduced into the study matrix at different times, thus they were not exposed to each test fluid, nor were the samples all exposed under the same test fuels. However, a standard sealant representative of those used in legacy equipment for gasoline and diesel use was evaluated in Fuel C, CE10a and CE25a test fuels. An ethanol-resistant sealant (developed specifically for E10 and E85 use) and the standard sealant combined with Teflon tape were evaluated in CE10a and CE25a. A total of three specimens