FUEL LINE

Fiber-reiaforced panels covered with PVF have been used for greenhouses. Transparent PVF film is used as the cover for flat-plate solar collectors (114) and photovoltaic cells (qv) (115). White PVF pigmented film is used as the bottom surface of photovoltaic cells. Nonadhering film is used as a release sheet ia plastics processiag, particularly ia high temperature pressing of epoxy resias for circuit boards (116—118) and aerospace parts. Dispersions of PVF are coated on the exterior of steel hydrauHc brake tubes and fuel lines for corrosion protection. 

The fluoroelastomers possess good mbber properties with the added advantages of being nonburning, hydrophobic, and solvent- and fuel-resistant. In addition to these, because of flexibiHty down to about —60° C, these polymers have been used in seals, gaskets, and hoses in army tanks, in aviation fuel lines and tanks, as well as in cold-climate oil pipeline appHcations. These polymers have also found appHcation in various types of shock mounts for vibration dampening (14,17). 

PBT-PET lower cost than PBT, better gloss and flexibihty than PET electrical/electronic, brake and fuel lines 326,327... 

Epichlorohydrin. Commercial polyester elastomers include both the homopolymer and the copolymer of epichl orohydrin with ethylene oxide. The very polar chloromethyl groups create basic resistance to oil for these polymers, and they have been extensively used in fuel lines however, the desire for lower fuel permeation is causing a search to be made for other polymers (10) (see Elastomers, synthetic-polyethers). 

The principal uses of ECO ate in automotive appHcations, eg, for fuel line and fuel vapor recirculation. There ate also some downhole seal appHcations where ECO is used. About 7000 t/yr of epichl orohydrin ate used in the United States. This is aU suppHed by the Zeon Corporation. 

The fuel systems of ground-based turbiaes are far less critical, siace coolants other than fuel can be used and fuel lines can be well iasulated. The tendency for deposit formation ia fuel is not a concern ia ground systems. 

If the boiler burns propane, natural gas, or fuel oil, then you ll need fluorocarbon o-rings on your fuel lines, valves, instrumentation and fittings. 

Table 12-4 is a summary of liquid fuel speeifieations set by manufaeturers for effieient maehine operations. The water and sediment limit is set at 1% by maximum volume to prevent fouling of the fuel system and obstruetion of the fuel filters. Viseosity is limited to 20 eentistokes at the fuel nozzles to prevent elogging of the fuel lines. Also, it is advisable that the pour point be 20 °F (11 °C) below the minimum ambient temperature. Failure to meet this speeifieation ean be eorreeted by heating the fuel lines. Carbon residue should be less than 1% by weight based on 100% of the sample. The hydrogen eontent is related to the smoking tendeney of a fuel. Lower... 

Since the reliability of gas turbines in the power industry has been lower than desired in recent years because of hot-corrosion problems, techniques have been developed to detect and control the parameters that cause these problems. By monitoring the water content and corrosive contaminant in the fuel line, any changes in fuel quality can be noted and corrective measures initiated. The concept here is that Na contaminants in the fuel are caused from external sources such as seawater thus, by monitoring water content, Na content is automatically being monitored. This on-line technique is adequate for lighter distillate fuels. For heavier fuels, a more complete analysis of the fuel should be carried out at least once a month using the batch-type system. The data should be input directly to the computer. The water and corrosion detecting systems also operate in conjunction with the batch analysis for the heavier fuels. 

A Btu meter may be used in the fuel-quality system as an aid in determining turbine system efficiency. A water capacitance probe is used for detection of water in the fuel line. A water-detecting device can be incorporated into the corrosion monitoring system. This monitoring device is based on detection of changes in the dielectric constant of unknown fluid components... 

The correct way to light a furnace (hot or cold) that bums gas or burns light oil is to start with a positive isolation, such as a slip-plate, in the fuel line. Other positive isolations are disconnected hoses, lutes filled with water (if the fuel is gas at low pressure), and double block and bleed valves closed valves without a bleed are not sufficient. Then ... 

A boiler had been shut down for the repair of a forced draft fan. A blind was not installed in the fuel gas line, nor apparently was a double block and bleed in the fuel line utilized. Gas leaked into the firebox during the repair period and was not removed. A severe explosion occurred during the attempt to light of. 

Figure 12.30 Potential uses of polyphosphazenes (a) A thin film of a poly(aminophosphazene) sueh materials are of interest for biomedical applications, (b) Fibres of poly[bis(trifluoroethoxy)phosphazene] these fibres are water-repellant, resistant to hydrolysis or strong sunlight, and do not burn, (c) Cotton cloth treated with a poly(fluoroalkoxyphosphazene) showing the water repellaney eonferred by the phosphazene. (d) Polyphosphazene elastomers are now being manufaetured for use in fuel lines, gaskets, O-rings, shock absorbers, and carburettor eomponents they are impervious to oils and fuels, do not bum, and remain flexible at very low temperatures. Photographs by eourtesy of H. R. Allcock (Pennsylvania State University) and the Firestone Tire and Rubber Company.

Corrosion inhibitor/lubricity improvement additives are used panicularly in militai y fuel for the dual puiyiose of passivating metal surfaces and improving the lubricating properties of the fuel in equipment such as fuel pumps. The militai y also specifies the use of a fuel system icing inhibitor as an additive to prevent filter blocking by ice crystal formation, because militai y aircraft tend not to use fuel line filter heaters, which are standard equipment on civil aircraft. 

A valve that closes in case of fire should be inserted in the oil fuel line to the oil-burning equipment and fitted as close to the tank as possible. It may be held open mechanically, pneumatically or electrically. Temperature-sensitive elements should be arranged to close the valve at a fixed maximum temperature, and sited close to the oil-fired plant and well above floor level. The operating temperature of the heat-sensitive elements should not be greater than 68°C (155°F) except where ambient temperatures in the vicinity of the plant may exceed 418°C (120°F), in which case the operating temperatures may be 183°C (200°F). 

Fuel lines should be mn where they will not be subject to high temperatures and must include protection with automatic and manual shut-off fire valves at the perimeter of the boiler house. Individual boilers should also be capable of isolation from this supply. Local requirements may vary on fuel supply systems, and these should be ascertained before installation. 

Operators also need to test flame failure controls, check the fuel delivery equipment (pumps, fuel lines, regulators, etc.), and keep adequate fuel consumption records. 

All fires should be extinguished, fuel lines isolated, valves closed, and lock out/tag out programs implemented to prevent accidents through the sudden release of some form of energy. 

The ability of nanoclay incorporation to reduce solvent transmission through polymers such as polyamides has been demonstrated. Data provided by de Bievre and Nakamura [203] of UBE Industries reveal significant reductions in fuel transmission through poIyamide-6/66 polymers by incorporation of a nanoclay hller. As a result, considerable interest is now being shown in these materials as both fuel tank and fuel line components for cars. Of further interest, the reduced fuel transmission characteristics are accompanied by significant material cost reductions. 

Finally, one variation on the weight-loss method— Fuel hose testing modified GM 9061 fill and plug method —applies for fuel line aspects of fuel containment—here the sample can be from an actual hose or its liner. 

Slow leak. Probable reasons may be stress cracking of tank liner, faulty operation of pressure relief valve, faulty coupling from tank to the feed line, or failure of the fuel line connection. 

Methanol would allow a transitional phase where some fuel cell vehicles use methanol, which is relatively simple to reform and would not present too big a change from our current system. However, methanol is toxic and very corrosive. Gas stations would need to be retrofitted to operate with it (new fuel tanks and fuel lines.) But, many gas station tanks are already methanol- compliant. 

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