Design safety factor

The safety factor incorporated in the design of reinforced PP parts is high in eomparison to unreinforced PP. A safety factor of 2-3 for fracture and 1.2 for change in dimensions is recommended. 

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Comparisons by von Stockar and Wilke [Ind. Eng. Chem. Fundam., 16, 89 (1977)] between the rigorous and the classical adiabatic design methods for packed towers indicate that the simple adiabatic method underestimates the packing depths by as much as a factor of 1.25 to 1.5. Thus, when using the (dassical adiabatic method, one should consider the possible need to apply a design safety factor. 

Design method used Woe Packed height, m Design safety factor... 

The estimated height of tower packing by assuming Hqq = 0.70 m and a design safety factor of 1.5 is... 

Flood factor is the usual design safety factor (e.g., 80% of flood, Ffiood = 0.80... 

For easy separations (less than 10 theoretical stages) a 20% design safety factor can be applied to a typical HETP value. 

For separations of 15 to 25 theoretical stages a 16% design safety factor should be applied to the HETP. 

Maximum Load Rating Bases. The maximum load rating will be based on the design safety factor and the yield strength of the material. Crown block beams are an exception and shall be rated and tested in accordance with API Spec 4E Specification for Drilling and Well Servicing Structures. ... 

Design Factor. The design safety factors shall be calculated as follows (see Figure 4-12) for the relationship between the design safety factor and rating ... 

Figure 4-12. Design safety factor and rating relationships [9],...

The maximum test load to be applied to the test unit shall be 0.80 x R x SFp, but not less than 2R. Where R equals the calculated load rating in tons, SFp is design safety factor. 

Traditional definitions of safety factors in terms of strength requirements, such as load-resistance factors or allowable stresses, are not applicable in blast resistant design. Safety factors arc more appropriately measured in terms of strain energy demand versus strain energy absorption capacity, Allowable deformations arc a practical method to quantify energy absorption capacity. 

Hoses built to United States standards have a four-to-one pressure design safety factor. This means that the maximum allowable working pressure (MAWP) must be one-fourth the hose s minimum burst pressure. This rating is generally specified at 72°F, and many users are unaware that, as the operating temperature increases, the hose assembly s MAWP decreases. [11]... 

The following adjustments, however, must be incorporated into the calculated flooding velocity to assure a reasonable design safety factor ... 

Nomenclatore A = area A, = area of tank bottom = area of coil Ag = equivalent area Ag = area of sides At = area of top Ai = equivalent area receiving heat from external coils A2 = equivalent area not covered with external coils Df = diameter of tank F = design (safety) factor h = film coefficient ha = coefficient of ambient air he = coefficient of coil hh = coefficient of heating medium hi = coefficient of liquid phase of tank contents or tube-side coefficient referred to... 

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