Engine seals

Demands for improved efficiency in aircraft gas turbines led to the use of a family of age hardenable, controlled expansion superaHoys for engine seals and casings. INCOLOY aHoys 903 [61107-16-2] (UNS N19903), 907 [107652-23-3] (UNS N19907), and 909 evolved from a continuing effort to improve the environmental resistance of this Cr-free, Fe—Ni—Co based system. 

A cutaway section of a cylindrical primary cell is shown in Fig. 3.20. The steel construction and intricately engineered sealing assembly reduce the... 

Aircraft engines Ceramic turbine nozzles in the APU (Auxiliary Power Unit Engine). Seals runners installed in different business jets such as Falcon, Citation and Learjet. Ceramic oil pump spacer enhance engine could start capability on APUs on Boeing 777 and 737 and all Airbuses. Cutter pins, which are used as a safety feature for air turbine starters. Ceramic wear indicator on Airbus APU starter brushes since 1997... 

Figure 6-17 Redesigned caustic tank with a properly-engineered seal pot. Courtesy...

Finally, deactivation of the catalyst by poisoning elements should be mentioned. Precious metal based catalysts are poisoned by sulfur oxides which mainly originate from the combustion of sulfur-containing fuel constituents, by phosphorus and zinc which mainly originate from some additives in the engine lubricating oil, and by silicium which was sometimes present in some engine seals (Table 21). Also, traces of lead, present in the fuel because of contamination of the fuel supply chain, made an important contribution to the deactivation of the catalyst in the past. 

Engineering Seale-Up of Renewable Hydrogen Production by Catalytie Steam Reforming of Peanut Shells Pvrolvsis Products... 

Figure 8.19 Redesigned caustic tank vent system containing a properly engineered seal pot on the overflow line.

There has been a long-standing commercial need for elastomers wifli a high degree of oil resistance. Such materials are very important to many industries where components come into contact with fluids (hydrocarbon and otherwise). Engine seals, specifically, should be able to withstand the fluids they are sealing without either becoming too soft or too brittle. 

Daley J R Ellaway T M Mays S TISPP UK Ltd. Dowty Engineered Seals (Institute of Materials)... 

The technology is available now for flexible and modular automatic inspection systems which make it possible to inspect rotational symmetric mass-produced articles with high throughput for surface defects and dimensions. The handling system of the Easier 03 is able to quickly and reliably separate and convey round parts of different sizes precisely to the sensor units. The optical inspection of engineered seals includes the inspection of geometrical properties and surface defects. 

Crane (1990). Engineered Sealing Products Catalog, John Crane, International, Inc. Morton Grove, IL. 

AEM is typically used because it gives an optimal balance in properties such as compression set, low-temperature flexibility, heat aging resistance, oil resistance, and excellent vibration damping. Therefore AEM is commonly preferred in automotive applications such as power steering, transmissions, and engine seals. 

Other forms of carbon-carbon composites have been or are being developed for space shutde leading edges, nuclear fuel containers for sateUites, aircraft engine adjustable exhaust nozzles, and the main stmcture for the proposed National Aerospace plane (34). For reusable appHcations, a siHcon carbide [409-21 -2] based coating is added to retard oxidation (35,36), with a boron [7440-42-8] h Lsed sublayer to seal any cracks that may form in the coating. 

Eig. 20. Cut view of Chlorine Engineers membrane bag cell a, manifold b, frame c, partition plate d, sealing plug e, recirculated NaOH inlet f, cathode g, anode h, cathode can i, membrane bag j, base k, butterfly valve 1, feed brine m, depleted brine n, caustic outlet. 

Textile uses are a relatively stable area and consist of the lamination of polyester foams to textile products, usually by flame lamination or electronic heat sealing techniques. Flexible or semirigid foams are used in engineered packaging in the form of special slab material. Flexible foams are also used to make filters (reticulated foam), sponges, scmbbers, fabric softener carriers, squeegees, paint appHcators, and directly appHed foam carpet backing. 

A. J. Baumgartner, ia R. A. Burton, ed.. Bearing and Seal Design in Nuclear Power Machiney, American Society of Mechanical Engineers, New York, 1967. 

Environmental Standardfor Re-Refined Engine Oil, Standard GS-3, Green Seal, Inc., Washington, D.C., 1992. 

The excellent properties of these fluoroelastomers come with a high price tag. Kalrez, for example, is extremely expensive ( 33—44/kg). These materials are used in automotive appHcations (seals, gaskets, fuel hose lines, engine parts, etc), where they can withstand under-hood temperatures. They are also used in equipment for oil and gas production and chemical processing. U.S. consumption in 1988 was 3100 t (76). 

Applications. Initial appHcations have been largely in military and aerospace areas. These include hydrauHc seals for military aircraft and fuel seals and diaphragms for both military and civiHan aircraft. Shock mounts for EZ are used on aircraft engines. Large fabric-reinforced boot seals are used in the air intake system on the M-1 tank. The material s useful temperature range, fuel and fatigue resistance, and fire resistance were determining factors in this appHcation. 

Extracted from Face-to-Face and End-to-End Dimensions of Ferrous Valves, ANSI B16.10—1973, with permission of the publisher, the American Society of Mechanical Engineers, New York. To convert inches to millimeters, multiply by 25.4. tNot shown in ANSI B16.10 but commercially available. jTliese dimensions apply to pressure-seal or flangeless bonnet valves only. 

Gas Holders Gas is sometimes stored in expandable gas holders of either the hquid-seal or dry-seal type. The hquid-seal holder is a familiar sight. It has a cylindrical container, closed at the top, and varies its volume by moving it up and down in an annular water-filled seal tank. The seal tank may be staged in several lifts (as many as five). Seal tanks have been built in sizes up to 280,000 m (10 X lO fE). The dry-seal holder has a rigid top attached to the sidewalls by a flexible fabric diaphragm which permits it to move up and down. It does not involve the weight and foundation costs or the hquid-seal holder. Additional information on gas holders can be found in Gas Engineers Handbook, Industrial Press, New York, 1966. 

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