Plastics wheel covers

For corrosive service the wheel can be made of stainless or nonferrous alloys can be all plastic in some designs or may be covered with rubber, lead, or plastic. Rubber-covered fans are usually limited in wheel peripheral velocity to 12,000-15,000 ft/min, although some wheels with certain types of rubber can run higher. ... 

Phenylene oxide Based (PPO) plastic that is a choice for electrical applications, housings for computers and appliances, both neat and in structural foam form. It has superior dimensional stability, moisture resistance due to styrene components, which, however, cause some sacrifice of weather and chemical resistance. Use includes automobile wheel covers, pool plumbing, consumer electronic external and internal components. 

Dot-matrix printers are still noisy, but the print wires and printhead are covered by a plastic dust cover, making them quieter than daisy-wheel printers. Also, dot-matrix printers use a more efficient printing technology, so the print speed is faster (typically in the range of 36 to 72cps). Some dot-matrix printers (like the Epson DFV series) can print at close to a page per second Finally, because dot-matrix printers are also impact printers, they can also use multipart forms. Because of these advantages, dot-matrix printers quickly made daisy-wheel printers obsolete. 

Polymers are common materials on land, sea, air, and space. Almost all cars, buses, light trucks, trailers, motorcycles, trains, boats, airplanes, and space shuttles contain plastics. POCs are found in the bumpers, fenders, doors, headlights, and wheel covers of automobiles, and their incorporation has reduced vehicle weight by approximately 250 pounds. The weight reduction also reduces fuel consumption and lowers the carbon dioxide (CO2) emissions. The advantages of using POCs over conventional materials in transport industry are the following ... 

Traditionally the steering wheel has comprised a metal skeleton covered in plastic. For some 40 years the coating was cellulose acetate butyrate (CAB) hard, scratch resistant - and slippery in warm weather. Increasing safety awareness led to the dished hub, and to over-moulding in PP and PVC. More recently, in meeting the requirements of ECE 21 and FMVSS 203, improved performance opposite head and body impact requirements has been achieved by the use of integral-skinned PUR foam for wheel covers and hub padding (Fig. 4.17). 

On the other hand, plastics have served well in the decorative segment of the wheel. Wheel covers, also known as hubcaps, are decorative parts attached to the steel wheel that covers the lug nuts. Generally, painted acrylonitrile-butadiene-styrene (ABS) and thermoplastic polyolefin (TPO) are used most often in making hubcaps. Chrome-plated emulsion ABS also is used in this application for customers who prefer the appearance of chrome. Chrome plating is a finishing treatment utilizing the electrolytic deposition of chromium. Many other plastics such as mass ABS and TPO have been attempted in this application with limited success. 

Fuel systems have already experienced an invasion by plastics. The use of plastics can be seen in fuel tanks, fuel rails, fuel pump parts, connectors, hoses, and fuel filters. Furthermore, external and internal lighting systems have already gone primarily to plastics. Wheel systems have adopted plastics much earlier in the construction of tires, wheel covers, and wheel house liners, although wheel systems remain primarily the domain of metals. 

Table 30.2 highlights the plastics materials used for wheel covers in various car models. Use of ASA in the Mercedes-Benz Vito is due to its better stability against ultraviolet (UV) radiation, which removes the need for chrome plating or painting [28]. 

In contrast to exterior surfaces, the interior plastic surfaces of most vehicles are pigmented rather than coated. The primary reason is that consumers prefer low-gloss, nonglare surfaces that blend harmoniously with interior fabrics and leather. Some plastics used on interior vehicle surfaces are coated to impart special characteristics, such as a soft touch and feel on control knobs antiglare and mar resistance on instrument panel top surfaces and soil and stain resistance for cushioned steering wheel covers. Another reason why interior plastic surfaces are rarely coated is because the potential of exposure to visible or UV radiation, environmental pollutants, chemicals, and mechanical insults is significantly less than for exterior surfaces. 

Large frontal areas create air turbulence and drag. Bodies derived from wind tunnel testing can provide a more smooth air flow around the vehicle. Details such as mirrors, rain gutters, trim, wheel wells and covers can also be more appropriate for air flow. Radial tires can reduce fuel consumption as much as 3%. Puncture-proof tires of plastic could save even more and eliminate the cost and weight of a spare tire and wheel. 

Plastic housing and parts Upper and bottom bodies Water tank Bottom wheel support Motor support and assembly Fan blades Fan covers 16.00 6.50 ... 

Examples of items often made of plastics include dishes and cups, containers, telephones, plastic bags for packaging and wastes, plastic pipes and fittings, automobile steering wheels and seat covers, and cabinets for appliances, radios, and television sets. In fact, such plastic items, along with textile fibers and synthetic rubbers, are so widely used that they are commonly taken for granted. 

Although few automobiles contain exterior body panels made of plastics, a number of components are plastic. Examples include bumpers, trim, light lenses, grilles, dashboards, seat covers, and steering wheels—enough plastics to account for an average of 250 lb per car. The increased emphasis on... 

Rollout Basket Shelves. Due to standard depth of a refrigerator, the reach must be accommodated for wheelchair-assisted individuals. Simple plastic-covered wire baskets with wheels on a rail allow access to the rear of the refrigerator. A lock-in mechanism should be designed into the shelf at its maximum extension, which should be set at two-thirds its depth. 

Medical Devices. The term "medical device" covers a broad range of instruments, implements, or implants which are used in medical care in hospitals, the physician ofSce or in home care. Examples include wheel chairs, contact lenses, pacemakers, endoscopes, vascular prostheses, extracorporeal blood circuits, joint or bone prostheses, thermometers, scalpels, catheters and syringes, just to name a few. As a consequence of this diversity in application, many different materials (biomaterials), including metals, ceramics, glasses, caibons, composites and plastics are u. And since many of these devices have moving parts, all kinds of different friction contacts, both lubricated and unlubricated, are encountered in medical devices. 

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