Default Settings - Head/Nozzle

Head

Interpolate Factor K for Ellipsoidal Head: When this box is cleared, the D/2h ratio is determined and rounded to 0.X precision before it is plugged into the K equation from Appendix 1-4(c) in Section VIII, Division 1.

Interpolate Factor K0 for Ellipsoidal Head: When this box is cleared, the D/2h ratio is determined and rounded to 0.X precision before it is plugged into the Ko determination using Table UG-33.1 in Section VIII, Division 1.

Conical Angle: The half-apex angle (half of the included angle) of the cone. This field is algebraically connected to the “Diameter”, “Small End Diameter”, and “Cone Height” fields. Entering the “Cone Angle” will solve for the “Cone Height”; entering the “Cone Height” will solve for the “Cone Angle.”

“Minimum Thickness” label: This is the label that will appear in the head/reducer form thickness preview sections on the internal and external pressure tabs. The label represents the smallest acceptable nominal thickness (input thickness), that will meet the loading, allowance, and tolerance requirements on the head/reducer.

Thin Out: The use table option will vary the default head thin out based on the head type and some other factors. This comes from some manufacturer data. When this option is not used, all head thin out values will default based on either the customary or metric inputs here.

Straight Flange: The length of the cylindrical straight flange of the head. Straight flange calculations are not performed automatically; a shell must be created to run calculations on the straight flange.

Torispherical Information: The options here only affect the “Torispherical” head type and do not affect the “ASME F&D” head type. When designing a torispherical head, entering the diameter value will automatically update the crown radius and knuckle radius fields based on these settings. The crown radius and knuckle radius fields may be altered after this update, but entering a new diameter value will update these fields again.

Nozzle

Nozzle Configuration: Select the basic nozzle attachment configuration from the drop-down menu.

Weld Detail Requirements: Because the wording in the code allows multiple interpretations, this allows the user to choose whether the weld detail requirements per UW-16 should be met in the corroded condition, the new condition, or both.

Calculate Reinforcement 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).

Allow Nozzle Design to Limit Vessel MAWP Rating: When this box is cleared and a new nozzle is created, the design pressure for the nozzle will be set to the MAWP of the vessel that is calculated thus far for the vessel, based on the other components.

Use Excess Wall Thickness for nozzle reinforcement calculations: When this box is selected, the design is in line with the code. When this box is cleared, the design will be more conservative than the code in terms of the determination of A1 (nozzle reinforcement from the host wall) for nozzle reinforcement calculations. When this box is cleared, the A1 value will be set to zero in the calculations.

Assume Use of Repad: Checking this box will start all new nozzles off with a repad. This can be changed in the nozzle form once the nozzle is created.

Show nozzle image on the report: The selection here is a global setting. Every nozzle report will be affected by the option picked here and cannot be overwritten at the design level. If the box is selected, the nozzle detail in the nozzle form (Nozzle Configuration) will appear on the nozzle report.

External Projection: The distance that the nozzle axis projects past the outside surface of the vessel wall.

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