Thin Wall Expansion Joint - Shell
Shell Information
Thickness: This applies to Toroidal Bellows, years 2013 and later, that are attached inside the shell. See Figure 26-1-1 sketch (c) for more information.
Shell Diameter: This applies to Toroidal Bellows, years 2013 and later, that are attached inside the shell. See Figure 26-1-1 sketch (c) for more information. This is the inside diameter. If the shell is subject to corrosion, please enter the dimensions in the corroded condition.
Long. Weld Jt. Eff. Shell: This applies to Toroidal Bellows, years 2013 and later, that are attached inside the shell. See Figure 26-1-1 sketch (c) for more information.
Shell Material
Material: A brief description of the component material. When the material selection dialog is used, the default description is based on settings on the Materials-Misc. tab under Tools > Defaults. For example, if the settings are for Spec and Type/Grade and the material is SA-516 Grade 70, this field will show SA-516 Gr. 70. If the settings are instead just for Spec, the field will show SA-516. The field may be edited by the user to say anything without breaking the relationship to the material database; while this flexibility can be very helpful, the user must take care to enter correct information.
Condition: A brief description of the component material. Similar to the "Material" field, the description will default a certain way based on settings on the Materials-Misc. tab under Tools > Defaults when the material selection is used. This field may be edited by the user without breaking the relationship to the material database. As with the “Material” field, the user must take care to enter correct information.
Modulus of Elasticity: The material modulus of elasticity based on the TM tables from Section II, Part D. The value shown here is based on the applicable TM table and the design temperature listed for the internal pressure condition. In cases where the temperature listed for the internal pressure condition exceeds the highest temperature entry for this material’s TM table, the value will be zero. There are several materials that do not have clear matches in these tables. When a clear match cannot be found by the software’s assignment criteria, the software will instead retrieve the modulus of elasticity from the external pressure chart assigned to the material. If this attempt also fails, then the value will be zero. This is more common with non-ferrous materials. Manually editing this field will sever the connection to the material in the database as indicated by the “Unlisted Material” caption.
Allowable Stress: The material allowable stress at the temperature listed for the internal pressure condition. When a 3.5:1 safety factor is specified in the vessel screen, this value comes from Section II, Part D (Table 1A for Ferrous Materials, Table 1B for Non-Ferrous Materials, and Table 3 for Bolting). If a 4:1 safety factor is specified, this value is calculated based on the ultimate strength from Table U in Section II, Part D; furthermore, the value is limited to the values listed in the allowable stress tables for yield and creep governed cases. In cases where the temperature listed for the internal pressure condition exceeds the highest temperature entry for this material’s stress line, the value will be zero. Manually editing this field will inform the software that the user is defining the material differently than what is stored in the database and the connection to the material in the database will be severed. This is indicated by the “Unlisted Material” caption.
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