Tubesheet - Tubesheet

Owned by Former user (Deleted)
Dec 11, 2015
4 min read

(Fixed, Floating, and U-Tube)

Several of these fields will be automatically completed when the Flange Search or the Expansion Joint Search is used. The content of those fields will be locked.

Tubesheet Information

Temperature: The maximum mean metal design temperature for the internal pressure case as defined in UG-20(a).

Outside Diameter: The component diameter in the new condition.

Bolt Load: The flange design bolt load. This applies to configurations b, c, d, e, f, B, C, and D. Ws represents the shell side design bolt load and Wc represents the tube side design bolt load.

Bolt Circle: The diameter of the circle that passes through the center of each bolt.

Use an Expansion Joint: On Fixed Tubesheet designs, select this box to indicate the use of an expansion joint. This will enable the Kj and Dj fields.

Axial Rigidity: The axial rigidity of the expansion joint, expressed as total force over elongation. This field is only applicable when an expansion joint is used.

Operating Bolt Load: The internal pressure operating bolt load. This applies to configurations b, c, d, e, f, B, C, and D. Wm1s represents the shell side operating bolt load and Wm1c represents the tube side operating bolt load.

Radial Distance: The moment arm from the bolt circle to the diameter on which the gasket reaction acts.

De: The maximum of the shell and channel gasket inside diameters, but not less than the maximum of the shell and channel flange inside diameters. If tubesheet acts as LAP, this is the diameter where the shear stress is acting. This field applies to configurations c, d, and f.

Shell side Corrosion Allowance: Corrosion allowance on the shell-side face of the tubesheet.

Channel side Corrosion Allowance: Corrosion allowance on the tube-side face of the tubesheet.

Per UG-23(e), calculate using: Select whether to calculate the allowable primary plus secondary stress using 3xS or 2xSy. Caution: If 3xS is selected and the value of S is determined at 90% of Sy, the allowable primary plus secondary stress will be 2.7xSy.

Pass Partition Groove Depth: The thickness removed on the tube-side face of the tubesheet to accommodate pass-partitions.

Radius to Outermost Tube Hole Center: The distance measured from the center of the tubesheet face to the center of the farthest tube-hole.

Midpoint of contact between flange and tubesheet: The diameter to the midpoint of contact between the lap flange and the tubesheet. This field is only available for configurations c, f, and C.

Expansion Joint Convolution ID: The inside diameter of the expansion joint at its convolution height. This field is only applicable when an expansion joint is used.

Nominal Thickness: This value is in the new condition. For the component to pass, this value must be at least the sum of the thickness necessary for pressure and temperature, corrosion allowances, and forming allowances or under-tolerances. If the thickness necessary for pressure and temperature is less than the thickness required by UG-16, the nominal thickness must be at least the sum of the UG-16 thickness and the tolerances, etc. In some cases, under-tolerance is not considered (e.g., for nozzle reinforcement, the under-tolerance of the nozzle neck is ignored). When “Solve for Thickness” is selected, the software will determine the smallest standard size that passes. The user is able to manually edit this value.

Perform: Select which calculation procedure to perform. Elastic Plastic Calcs only apply to configurations with an integral shell or channel (a, b, c, e, f and A) and to the design loading cases (1,2, and 3) under specific circumstances. Simply Supported only apply to configurations in which the tubesheet is integral with the shell or channel (a, b, c, e, f and A) and to the design loading cases (1, 2, and 3) under specific circumstances; the simply supported calculations do not consider the effect of the stiffness of the integral channel or shell in the determination of the tubesheet stresses.

Extended as Flange: Necessary for tubesheets that have holes for through bolting. This is selected by default. This field is only used for configuration d.

Info Used for Extension Calculations: Options are Shell, Channel, and Shell/Channel. When Shell/Channel is selected, it will use the greatest value between them. Shell/Channel is selected by default.This field is only used for configuration d.

Tubesheet 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.

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.

B-Table: The external pressure table assigned to the material in the allowable stress tables in Section II, Part D. The table is used to determine the external pressure strength of the component and also the longitudinal compressive strength. Selecting a Factor B table other than the one assigned to the material will sever the connection to the material in the database as indicated by the “Unlisted Material” caption.

Poisson: Poisson's ratio for the selected material.

(T'): The metal temperature of the tubesheet at the rim as expected during operation. It is usually not conservative to substitute the tubesheet design temperature for T'.