Design cushioning

Tissue Conditioners. Tissue conditioners are gels designed to alleviate the discomfort from soft-tissue injury, eg, extractions. Under a load, they exhibit viscous flow, forming a soft cushion between the hard denture and the oral tissues. The polymer in tissue conditioners is often the same as that used for resilient liners. The liquid is a plasticizer containing an alcohol of low volatility (219,220). 

A poorly designed discharge manifold can cause shock waves and excessive pressure peaks. This manifold should be as short and direct as possible, avoiding any sharps turns. The conventional small atmospheric air chamber, often furnished with pumps, supplies only a moderate cushioning effect. For best results, this air chamber should be supplemented by a large atmospheric air chamber or by a precharged pulsation dampener. 

The brittle nature of glasses at normal temperatures makes them inappropriate for use in locations where severe impacts are likely to be encountered. In the design of pipelines or other equipment it is possible to use normal engineering assembly techniques provided that suitable gaskets or cushioning are provided at joints and supports and that care is taken in tightening bolts to avoid unequal or localised stresses. 

Ogive, Rifle Grenade. A hollow metallic item designed for attachment to the forward end of a practice rifle grenade. It cushions the impact and permits reuse of the grenade Ref OrdTechTerm (1962), 208-R... 

M.E. Gigliotti, Design Criteria for Plastic Package-Cushioning Materials , PLASTEC Rept 4 (1961) 3)M.C. StCyr, State of the Art,... 

PE from recovered material, has a nominal 2.2 Ib/cu ft density and is designed for protective cushion packaging as well as general cushioning applications. Graphical information is provided on the dynamic cushioning performance of the foam. 

The one-shot process was developed in the 1950s. It is a technique by which the polyol and the isocyanate are mixed together. Without help, however, the reaction would be too slow to be useful. For this reason, the key to the process is the development of a formulation that accelerates tlie isocyanate reaction. We will discuss the design of a formulation to meet a specific end use in the next chapter. To complete our discussion of the processes by which polyurethane foams are made, consider the formulation for a conventional foam used for furniture cushions (Table 2.3). 

In the world of polyurethanes, standard methods describe the properties of the materials. While the conventional methods of analysis are necessary for compliance with the physical design of a system, our task must include chemical tests, and they must be developed on an ad hoc basis. Nevertheless, conventional methods for analyzing a polyurethane are very helpful and are reviewed here. Our focus will be on the effects of the polyurethane chemistry on fluids with which it comes into contact. Because this is different from the typical use pattern, some of the standard methods used to produce seat cushions, for example, will not apply. We will discuss several methods but not in the traditional order. 

Cylinder, Recoil A cylinder with component parts designed to cushion the backward motion of a cannon by springs, or by the slow passage of air or fluid thru holes in the piston when the gun is... 

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