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Impact protection

Flakes, chips, sheets, blocks used for impact protection and damping in the packaging of various products such as cameras, electronic devices. .. [Pg.56]

When products are stored in warehouses for long periods, the foam packaging must not creep by more than about 10%, or the impact protection will... [Pg.15]

In the future, body armor may be flexible. Experimentation is underway with shear thickening material using polyethylene glycol (PEG) with nanoparticles that remain flexible until rapidly struck such as with a bullet whereupon it acts as a solid protecting the wearer from the major impact. Kevlar is also being employed to protect space craft and space men from discarded space junk and small meteors. Thus, experimentation in body armor is being applied to additional areas where impact protection is essential. [Pg.521]

Ref 25a). Here i is used as a fuel in proplnt compns which are used to generate a gas for inflation of impact-protective gas bags in automobiles during a collision... [Pg.325]

Analysis of these effects is difficult and time consuming. Much recent work has utilized two-dimensional, finite-difference computer codes which require as input extensive material properties, e.g., yield and failure criteria, and constitutive laws. These codes solve the equations of motion for boundary conditions corresponding to given impact geometry and velocities. They have been widely and successfully used to predict the response of metals to high rate impact (2), but extension of this technique to polymeric materials has not been totally successful, partly because of the necessity to incorporate rate effects into the material properties. In this work we examined the strain rate and temperature sensitivity of the yield and fracture behavior of a series of rubber-modified acrylic materials. These materials have commercial and military importance for impact protection since as much as a twofold improvement in high rate impact resistance can be achieved with the proper rubber content. The objective of the study was to develop rate-sensitive yield and failure criteria in a form which could be incorporated into the computer codes. Other material properties (such as the influence of a hydrostatic pressure component on yield and failure and the relaxation spectra necessary to define viscoelastic wave propagation) are necssary before the material description is complete, but these areas will be left for later papers. [Pg.196]

The resulting films have a very high mechanical resistance. They are particularly important for stone impact protection in automobile finishes, for coating high-quality industrial goods, for electrical insulation, as well as for coil coating applications. Solvent-free products are used in liquid form as thick-layer systems or in solid form for powder coatings. [Pg.66]

Lau, I.V. and Viano, D.C., How and When Blunt Injury Occurs ImpUcations to Frontal and Side Impact Protection. Proceedings of the 32nd Stapp Car Crash Conference, pp. 81-100, SAE Paper No. 881714, Society of Automotive Engineers, Warrendale, PA, 1988. [Pg.930]

Equation (7.24) indicates that, if the foam is required to have a certain compressive yield stress, yet minimum density, the yield stress of the polymer in the bulk state must be high. Polystyrene has a yield stress at high strain rates of 120MPa whereas polypropylene has a yield stress of 60 MPa. Consequently, an EPS helmet will have a lower density than an EPP helmet designed to meet the same impact tests. Therefore, EPS is optimal for helmets that offer single-impact protection. [Pg.426]

Multipiece spoiler Impact protection parts Bumper... [Pg.997]

Impact attenuation is initiated by the outer shell, which delocalizes and spreads the direct load into the liner to manage impact energy. To consistently maintain its protective performance and systematic function, the shell must provide the necessary stiffness, toughness, and stability across a wide array of end-use impact conditions. As a result, sports helmets are most commonly constructed with an injection-molded rigid polymer outer shell. The selected thermoplastic polymers influence the level of impact protection and are often divided into three performance categories high-impact resistance, moderate-impact resistance, and general purpose. [Pg.217]

In 2003, Schutt Sports, Inc. was the first to introduce TPU cushioning into American football helmets (Schutt Sports, 2014). The mechanical performance of this inner liner system was described previously (Caswell et al., 2007). The sustained popularity of the inner liner is reflected in the newly available VTD helmets that contain a similar TPU cushioning design with varying thickness and durometer hardness. Additional helmet models have recently included a new engineered TPU material that displays viscoelastic and shear-thickening behavior for enhanced impact protection (Schutt Sports, 2014). The non-Newtonian, dilatant material increases in stiffness with the rate of shear strain, such that the stress and strain characteristics are dependent on the rate of loading. [Pg.222]

The third heuristic, Create multilayered body armor, can be explained by the fact that combining materials may create unique features of armor impact damping, thermal insulation, penetration resistance, lightness, and so on. The fourth heuristic, Introduce shock-absorbing layers, only adds specificity and sophistication to the previous one and reminds inventors that impact protection is extremely important and that this can be improved using a layer of fat, for example, to protect a brain against impact. [Pg.357]

Polyolefins are used in automotive industry due to their low cost, good weather resistance, and excellent properties. They can be used in many parts to reduce the vehicle weight, save fuel, increase comfort, and reduce CO2 emission. Polyethylene (UHMWPE or HDPE), for example, is used to absorb vibration and noise and for impact protection. Polypropylene is one of the lightest polyolefins, and with a proper design, an improvement in the passenger safety can be achieved. Polypropylene can also be used in bumper systems to absorb the kinetic energy. [Pg.9]

Clear high impact PVC PVC will provide impact protection comparable to laminated safety glass, but will not be as resistant to the effects of chemicals in the hood. [Pg.156]

Most practical helmet designs are a compromise between impact protection and other considerations (e.g., bulk and weight, visibility, coi ort, ability to communicate). Their efficacy has been demonstrated repeatedly by experiment and accident statistics. [Pg.255]

A safety standard that provides performance and testing requirements for industrial helmets, commonly known as hard hats. It established the types and classes of pro-teetive helmets, depending on the type of hazard encountered. Industrial head protective helmets meeting the requirements of the standard are classified as Type I for top protection or Type II for lateral impact protection. Both types are tested for impact attenuation and penetration resistance. Type II helmet performance requirements inelude eriteria for impact energy attenuation from impacts from the front, back, and sides as well as the top off-center penetration resistance and chin strap retention. [Pg.31]

The primary standards covering minimum requirements for the design, performance, testing, and classification of protective footwear against a variety of hazards that can potentially result in injury (see Figure A.6). These tests include impact resistance for the toe area of footwear compression resistance for the toe area of footwear metatarsal impact protection that reduces the chance of injury to the metatarsal bones at the top of the foot conductive properties that reduce hazards... [Pg.38]

Lenses are tested to withstand the impact of a 2.5-cm (1-inch) ball dropped from 127 cm (50 inches), plus a penetration test for plastic lenses as required by American National Standards Institute (ANSI) Z87 for all eye and face protectors, two-level classification for impact protection. See ANSI Z87.1-2003, Standard for Occupational and Educational Eye and Face Protection Devices. [Pg.45]

As part of American National Standards Institute (ANSI) Z87 two-level classification for impact protection for eye and face protectors, high impact lenses and all frames... [Pg.154]

Impact protection for driver from steering column system... [Pg.178]


See other pages where Impact protection is mentioned: [Pg.2282]    [Pg.69]    [Pg.69]    [Pg.233]    [Pg.36]    [Pg.41]    [Pg.2037]    [Pg.2571]    [Pg.2551]    [Pg.2286]    [Pg.54]    [Pg.923]    [Pg.500]    [Pg.11]    [Pg.85]    [Pg.214]    [Pg.216]    [Pg.223]    [Pg.577]    [Pg.288]    [Pg.299]    [Pg.631]    [Pg.41]    [Pg.27]    [Pg.40]    [Pg.46]    [Pg.135]   
See also in sourсe #XX -- [ Pg.313 ]

See also in sourсe #XX -- [ Pg.289 ]




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Impact protection standards

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