Nozzle
External Projection: The distance that the nozzle axis projects past the outside surface of the vessel wall.
Weld 41: The weld leg of the nozzle neck perimeter weld on the outside of the vessel.
Internal Projection: The distance that the nozzle axis projects past the inside surface of the vessel wall.
Weld 43: The weld leg of the nozzle neck perimeter weld on the inside of the vessel. In the case of Partial Penetration or UW-16(k) nozzle configuration, Weld 43 refers to the inner fillet weld between the nozzle neck and the host thickness.
Factor F: This value represents a correction for the stress direction in cones and cylinders and is only available for input when the nozzle is in a cone or a cylinder and the nozzle is integrally reinforced (i.e., the nozzle is attached by full penetration groove welds and a repad is not used). Review the definition for F in UsG-37 and Figure UG-37 before editing this value; a value of 1.0 is conservative.
Use Repad: Select this box to add a repad to the nozzle.
Reinforcing Pad
The following fields are only available if a repad is used.
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. Density: The material density based on table PRD from Section II, Part D. For those materials that did not have a clear match in this table, every effort was made to assign conservative values. Manually editing this field will sever the connection to the material in the database as indicated by the "Unlisted Material" caption. Stress (Hot): 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. Stress (Cold): The material allowable stress at 70 °F (20 °C). 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. Manually editing this field will sever the connection to the material in the database as indicated by the “Unlisted Material” caption. Apply Split Repad Penalty: Select the box to apply a multiplier of 0.75 to the value of A5 used in the nozzle reinforcement and weld strength calculations. This 25% penalty is applied per the conditions listed in UG-37(h) and was introduced in the 2009 addenda to the 2007 edition of Section VIII, Division 1. Diameter: The outside diameter of the reinforcing pad. If the pad is not circular in shape, enter the diameter of the reinforcing pad for the cross-section in question as though the repad were circular. For example, when looking at the tangential cross-section of an off-set nozzle, the diameter of the pad would be entered as the distance from one edge of the pad on one side of the nozzle to the opposite edge of the pad on the other side of the nozzle measured along the chord length of the opening. te: The thickness of the reinforcing pad. Groove Depth: The depth of the groove weld deposited in the repad at the perimeter of the nozzle neck. The default value is full penetration. Weld 42: The weld leg of the repad perimeter weld. |
Custom Limit of Reinforcement: When the Enable box is selected, the value entered will be used to limit the parallel limit of reinforcement determined per UG-40(b). Using this field may result in reducing the available area of reinforcement values and make meeting the UG-37 or Appendix 1-7(a) reinforcement requirements more difficult. For example, nozzles in close proximity may not have overlapping limits of reinforcement, so the code would require a reduction in this value and would thereby increase the difficulty of meeting UG-37 requirements. See UG-42 (UG-39 for nozzles in flat heads) for more information. In addition, nozzles typically exempt from reinforcement calculations will lose their exemption if this field is used.
Total Nozzle Weight: The weight of the nozzle can be specified by the user or calculated by the software. This value will be dynamically calculated by the software unless the user manually enters a value.Once input has been manually entered, the value becomes static and is no longer calculated.
Calc Reinf. For nozzles meeting UG-36(c)(3)(a): Select this box to force nozzle reinforcement calculations. Calculations will be performed even for cases that are exempt as small openings per UG-36(c)(3)(a).
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