ASME PTB-7

Abstract

This criteria document covers the development of the tubesheet (TS) design rules for the U-tube, Fixed, and Floating Head TS Heat Exchangers (HE) configurations contained in Part UHX of Section VIII Division 1, 2013 Edition. It applies also to Paragraph 4.18 of Section VIII, Division 2 which is entirely based on Part UHX. <br>The free body diagram of the HE, the equilibrium and compatibility equations, the solution of resulting differential equations and all intermediate steps are provided to show the derivation of:&#160; </span><ul> <li>the deflection and the rotation at any radius of the TS,&#160;</li> <li>the bending and shear stress at any radius of the TS,&#160;</li> <li>the axial stresses in the tubes at any radius of the TS,&#160;</li> <li>the axial stretch force acting in the shell,&#160;</li> <li>the axial displacement of the shell.</li></ul> <br>The document provides the technical basis of the following items:&#160; <ul> <li>the required loading case combinations,&#160;</li> <li>the acceptance criteria for each TS configuration, as applicable,</li> <li>the TS characteristics including the Effective Elastic Constants,&#160;</li> <li>the TS extended as a flange.</li></ul> <br>The following effects are in addition to the above basic items:&#160; <ul> <li>the effect of different shell material or thickness adjacent to the TS,&#160;</li> <li>the effect of plasticity at TS-shell-channel joint,&#160;</li> <li>the effect of radial differential thermal expansion between the TS and integral shell and channel,&#160;</li> <li>the tubesheet calculated as a simply supported TS.</li></ul><br>