Design strength-critical

This review shows what the veteran plastic designer knows that plastic products are often stiffiiess critical, whereas metal products are usually strength critical. Consequently, metal products are often made suffer than required by their service conditions, to avoid failure, whereas plastic products are often made stronger than necessary, for adequate stiffiiess. 

Pipe analysis Hydrostatic design stress Tfensile stress at 5deld Tfensile creep ruptm stress Compression strength Critical stress intensity factor... 

The major load-bearing member of cord—mbber composites is the cord, which provides strength and many other critical properties essential for tire performance. Cords in pHes form the stmctural backbone of the tire. The mbber plays the important but secondary role of transmitting load to the cords via shearing stresses at the cord—mbber interface. Other expected performance characteristics of the tire are due to design and manufacturing processes. Table 5 (96) identifies several tire performance characteristics and how they are dependent on tire cord properties. 

Because of this, the data listed in Table 15.7 for ceramic materials differ in emphasis from those listed for metals. In particular, the Table shows the modulus of rupture (the maximum surface stress when a beam breaks in bending) and the thermal shoek resist-anee (the ability of the solid to withstand sudden changes in temperature). These, rather than the yield strength, tend to be the critical properties in any design exercise. 

As before, the data presented here are approximate, intended for the first phase of design. When the choice has narrowed sufficiently, it is important to consult more exhaustive data compilations (see Further Reading) and then to obtain detailed specifications from the supplier of the material you intend to use. Finally, if the component is a critical one, you should conduct your own tests. The properties of ceramics are more variable than those of metals the same material, from two different suppliers, could differ in toughness and strength by a factor of two. 

The design of this alloy was unique in that it utilized phase stability and other predictive techniques to balance the levels of critical elements (Cr, Mo, Co, Al, Wand Ta), thereby maintaining the hot corrosion resistance of IN-738 at higher strength levels without compromising phase stability. Most... 

No one steel exceeds the tensile modulus of mild steel. Therefore, in applications in which rigidity is a limiting factor for design (e.g., for storage tanks and distillation columns), high-strength steels have no advantage over mild steel. Stress concentrations in mild steel structures are relieved by plastic flow and are not as critical in other, less-ductile steels. 

The mixer manufacturer should always be consulted for proper mechanical features design and strength characteristics, such as horsepower, gear rating AGA, shaft diameter, shaft deflection, critical speeds, bottom steady bearing, and side shaft bearings. 

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