Primary stress local

On the other hand, the stresses from the inward radial load could he either a primary local stress or secondary stress. It is a primary local stress if it is produced from an unrelenting load or a secondary stress if produced by a relenting load. Either stress may cause local deformation but will not in and of itself cause the vessel to fail. If it is a primary stress, the stress will be redistributed if it is a secondary stress, the load will relax once slight deformation occurs. 

A local primary stress is produced either by design pressure alone or by other mechanical loads. Local primary... 

The bending stresses associated with a local loading are almost always classified as secondary stresses. Therefore, the membrane stresses from a WRC-107-type analysis must be broken out separately and combined with general primary stresses due to internal pressure, for example. 

The structural solution computes the full 3D elastic-plastic deformation and stress fields for the solid components of the stack. The primary stress-generation mechanism in the SOFC is thermal strain, which is calculated using the coefficient of thermal expansion (CTE) and the local temperature difference from the material s stress-free temperature. These thermal strains and mismatches in thermal strains between different joined materials cause the components to deform and generate stresses. In addition to the thermal load, the stack will have boundary conditions simulating the mechanical constraints from the rest of the system and may also have external mechanical preloading. The stress solution is obtained based on the imposed mechanical constraints and the predicted thermal field. Figure 26.6 shows... 

Local primary stress is produced by the design pressure alone or by other mechanical loads. It has some self-limiting characteristics. If the local primary stress exceeds the yield point of the material, the load is distributed and carried by other parts of the vessel. 

Primary plus secondary stress intensity. The maximum stress intensity S as based on the primary or local membrane stresses plus the primary bending stress plus the secondary stress (cr m or ctl + (7b -f X) 2) cannot exceed the... 

Primary stresses, including general primary membrane stress, local primary membrane stress, and primary bending stress Secondary stresses Peak stresses... 

The SMI, SM2, and SMS output parameters are section bending moments in the piping about the. three local element axes (x, y, z). These three output parameters are taken from the ABACUS output and used in ASME B PV Code Section III Div I - NB piping limit equations. The primary and the primary plus secondary stress range limits are evaluated for this anaiysis. The primary stress limit is evaluated for the pressure only load case for the cases listed in Table 9-32. The primary plus secondary stress limit is a limit on the stress intensity range. This requires a stress state at each end of the range. The range used to evaluate the limit is ... 

Primary glide occurs on the (111) planes. Shear of a carbon layer over a metal layer (or vice versa), when the core of a dislocation moves, severely disturbs the symmetry, thereby locally dissociating the compound. Therefore, the barrier to dislocation motion is the heat of formation, AHf (Gilman, 1970). The shear work is the applied shear stress, x times the molecular (bond) volume, V or xV. Thus, the shear stress is proportional to AHf/V, and the hardness number is expected to be proportional to the shear stress. Figure 10.2 shows that this is indeed the case for the six prototype carbides. 

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