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At least 217 records · Page 12

Advanced fuel system technology for utilizing broadened property aircraft fuels

Factors which will determine the future supply and cost of aviation turbine fuels are discussed. The most significant fuel properties of volatility, fluidity, composition, and thermal stability are discussed along with the boiling ranges of gasoline, naphtha jet fuels, kerosene, and diesel oil. Tests were made to simulate the low temperature of an aircraft fuel tank to determine fuel tank temperatures for a 9100-km flight with and without fuel heating; the effect of N content in oil-shale derived fuels on the Jet Fuel Thermal Oxidation Tester breakpoint temperature was measured. Finally, compatibility of non-metallic gaskets, sealants, and coatings with increased aromatic content jet fuels was examined.

Reck, G. M.↗

Ceramic-Cord Gas Seal

High-temperature gasket material seals at temperatures above 1,100 degrees C. Concentric exhaust pipes are typical of applications in which ceramic-cord seals might be used. Cord is crushed to form seal between inner and outer pipes when inner pipe is expanded into place. Typical applications include engine exhaust ducts or hot pipes passing through firewalls.

Etzel, C. W.↗

Edge Supports for Photovoltaic Modules

Mounting strips patterned after glazing gaskets. Easy to install supports for rooftop solar modules consist of extruded rubber mullions with locking zippers. Supports cut to length with utility knife and installed without special tools. Adaptable to many different roof configurations.

Maloney, T. J.↗

Process for preparing perfluorotriazine elastomers and precursors thereof

Perfluoroether triazine elastomers having improved properties and utility in seals, gaskets, sealing components and the like are prepared from oligomeric imidoylamidines that have, in turn, been prepared by the process of (1) reacting a perfluorodinitrile with liquid ammonia to yield a perfluorodiamidine, (2) isolating the perfluorodiamidine, (3) reacting the isolated diamidine with a perfluorodinitrile to yield a perfluoror(imidoylamidine) dinitrile, and then repeating step (1), (2), and (3) to sequentially grow an oligomer of desired molecular size. The isolated amidine and nitrile intermediates are also described.

Rosser, R. W.↗

Synthetic Organic Materials in Nuclear Powerplants

Report aids plant designers and qualification engineers in ensuring that organic materials in nuclear powerplants will perform satisfactorily in such safety-related equipment as insulation on motor windings, pump diaphragms, motor and pump lubricants, and pump seals and gaskets. Report provides information for service that may include both mild and harsh nuclear environments.

Bouquet, F. L.↗

Perfluoro (Imidoylamidine) diamidines

Perfluoroether triazine elastomers having improved properties are prepared from oligomeric imidoylamidines that were in turn, prepared by the process of: (1) reacting a perfluorodinitrile with liquid ammonia to yield a perfluorodiamidine, (2) isolating the perfluorodiamidine, (3) reacting the isolated diamidine with a perfluorodinitrile to yield a perfluoro(imidoylamidine) dinitrile, and then repeating the steps to sequentially grow an oligomer of desired molecular size. The isolated amidine and nitrile intermediates are also disclosed. The elastomers can be fashioned into seals, gaskets, and sealing components and the like.

Rosser, R. W.↗

Radiation Effects on Polymer Properties

Report compiles data on effects of radiation on physical properties of synthetic organic materials. Emphasis on materials of interest to nuclear-equipment and nuclear-reactor designers. Data covers five categories of polymeric materials: Insulators, elastomeric seals and gaskets, lubricants, adhesives, and coatings. More than 250 materials represented.

Bouquet, F. L.↗

Elastomers Compatible With High-Pressure Oxygen

Compatibility increased by fluorination. Report describes experiments aimed at improving compatibility of some fluorinated elastomers with high-pressure oxygen. Such elastomers needed for seals, gaskets, and positive-expulsion devices used with high-pressure oxygen. Oxygen - compatibility tests carried out on five elastomers chosen on the basis of literature survey.

Martin, Jon W.↗

Inflatable Perimeter Seal

Effective, inexpensive pressure seal between two flat surfaces formed from silicone rubber tubing. Resembling refrigerator seal, pressure seal especially useful where shape of sealed region irregular or subject to change. Unlike gaskets and O-rings, tubing seals require no machined grooves or custom-made parts and not adversely affected by warpage of sealed surfaces.

Shepherd, Clayton C., Jr.↗

Glass-to-Metal Seal Against Liquid Helium

Simple compression joint with indium gasket forms demountable seal for superfluids. Seal developed for metal lid on glass jar used in experiments on liquid helium. Glass container allows contents to be viewed for such purposes as calibration of liquid-level detectors and adjustments of displacement plungers. Seal contains liquid helium even when temperature drops below 2.19K. Made from inexpensive, commercially available materials and parts.

Watkins, John L.↗

Resistance heating of Fe and W in diamond-anvil cells

A new method for internally heating a diamond-anvil cell is described. Fine wires of iron or tungsten are resistively heated in a gasketed cell, thus providing a uniformly distributed pressure that can be measured in situ by employing the ruby scale. Temperatures of several thousand degrees have been measured by fitting a black body radiation function to the spectrum of the hot wire taken with an optical multichannel analyzer. Temperatures as high as the melting temperature of tungsten have been achieved. The alpha-gamma and alpha-epsilon phase transitions of iron have been studied, and the results show excellent agreement with previous data obtained with piston-cylinder or externally-heated diamond cells.

Boehler, R.↗

Ceramic Welding-Torch Extension

Simple attachment extends torch to difficult-to-reach joints. Bushing, gasket, and extender mate with gascup to form extension assembly. Extender designed and fabricated to suit particular job.

Gordon, Stephen S.↗

Adiabatic diesel engine component development: Reference engine for on-highway applications

The main objectives were to select an advanced low heat rejection diesel reference engine (ADRE) and to carry out systems analysis and design. The ADRE concept selection consisted of: (1) rated point performance optimization; (2) study of various exhaust energy recovery scenarios; (3) components, systems and engine configuration studies; and (4) life cycle cost estimates of the ADRE economic worth. The resulting ADRE design proposed a reciprocator with many advanced features for the 1995 technology demonstration time frame. These included ceramic air gap insulated hot section structural components, high temperature tribology treatments, nonmechanical (camless) valve actuation systems, and elimination of the cylinder head gasket. ADRE system analysis and design resulted in more definition of the engine systems. These systems include: (1) electro-hydraulic valve actuation, (2) electronic common rail injection system; (3) engine electronic control; (4) power transfer for accessory drives and exhaust energy recovery systems; and (5) truck installation. Tribology and performance assessments were also carried out. Finite element and probability of survival analyses were undertaken for the ceramic low heat rejection component.

Hakim, Nabil S.↗

Welding torch gas cup extension

The invention relates to a gas shielded electric arc welding torch having a detachable gas cup extension which may be of any desired configuration or length. The gas cup extension assembly is mounted on a standard electric welding torch gas cup to enable welding in areas with limited access. The gas cup assembly has an upper tubular insert that fits within the gas cup such that its lower portion protrudes thereform and has a lower tubular extension that is screwed into the lower portion. The extension has a rim to define the outer perimeter of the seat edge about its entrance opening so a gasket may be placed to effect an airtight seal between the gas cup and extension. The tubular extension may be made of metal or cermaic material that can be machined. The novelty lies in the use of an extension assembly for a standard gas cup of an electric arc welding torch which extension assembly is detachable permitting the use of a number of extensions which may be of different configurations and materials and yet fit the standard gas cup.

Gordon, Stephen S.↗

Dynamic, High-Temperature, Flexible Seal

New seal consists of multiple plies of braided ceramic sleeves filled with small ceramic balls. Innermost braided sleeve supported by high-temperature-wire-mesh sleeve that provides both springback and preload capabilities. Ceramic balls reduce effect of relatively high porosity of braided ceramic sleeves by acting as labyrinth flow path for gases and thereby greatly increasing pressure gradient seal can sustain. Dynamic, high-temperature, flexible seal employed in hypersonic engines, two-dimensional convergent/divergent and vectorized-thrust exhaust nozzles, reentry vehicle airframes, rocket-motor casings, high-temperature furnaces, and any application requiring non-asbestos high-temperature gaskets.

Steinetz, Bruce M.↗

Technical Evaluation Motor no. 5 (TEM-5)

Technical Evaluation Motor No. 5 (TEM-5) was static test fired at the Thiokol Corporation Static Test Bay T-97. TEM-5 was a full scale, full duration static test fire of a high performance motor (HPM) configuration solid rocket motor (SRM). The primary purpose of TEM static tests is to recover SRM case and nozzle hardware for use in the redesigned solid rocket motor (RSRM) flight program. Inspection and instrumentation data indicate that the TEM-5 static test firing was successful. The ambient temperature during the test was 41 F and the propellant mean bulk temperature (PMBT) was 72 F. Ballistics performance values were within the specified requirements. The overall performance of the TEM-5 components and test equipment was nominal. Dissembly inspection revealed that joint putty was in contact with the inner groove of the inner primary seal of the ignitor adapter-to-forward dome (inner) joint gasket; this condition had not occurred on any previous static test motor or flight RSRM. While no qualification issues were addressed on TEM-5, two significant component changes were evaluated. Those changes were a new vented assembly process for the case-to-nozzle joint and the installation of two redesigned field joint protection systems. Performance of the vented case-to-nozzle joint assembly was successful, and the assembly/performance differences between the two field joint protection system (FJPS) configurations were compared.

Cook, M.↗

Flight set 360H005 (STS-28) seals, volume 4

The performance is assessed of the 360H005, Fifth flight, Redesigned Solid Rocket Motors (RSMR) in respect to joint sealing issues as seen from post flight inspection of the seals and sealing surfaces. The factory joint disassembly inspections have resumed for 360H005. The new factory joint grease application is in effect and now can be assessed during the disassembly process. The RSRM is illustrated consisting of capture feature field joints as is the J-joint insulation configuration. The nozzle-to-case joint design is also illustrated, which includes 100, 7/8 inch radial bolts in conjunction with a wiper O-ring and modified insulation design. The ignition system seals and a cross section of the igniter are illustrated. The configuration of all the internal nozzle joints are also shown. The postflight inspection of both motors showed the seal components to be in excellent condition except for the indentation found on the inner primary seal of the right hand inner igniter gasket, aft face. Detailed inspection results, and inspections performed by the O-ring Inspection Team are presented.

Curry, Jeffrey T.↗