Pressure Vessel Engineering Curriculum
Nozzles
Module from the Pressure Vessel Engineering Curriculum curriculum.
Module 4 - Nozzle Reinforcement (UG-37 and UG-40) · Learning Objectives · 1. State when reinforcement is required per UG-36 (size, location) · 2. Compute required area A = d*tr*F and available areas A1-A5 · 3. Apply reinforcement-limit parallel-to-vessel-axis and normal-to-vessel-surface · 4. Select self-reinforced forged nozzles vs pad reinforcement · 5. Recognize need for weld pad repad vent (telltale) during hydrotest · Nozzle Reinforcement Area Summary
| Area | Source | Formula | Limit | Notes | Ref |
|---|---|---|---|---|---|
| A | Required area | d*tr*F + 2*tn*tr*F*(1-fr1) | - | Need to be replaced | UG-37(c) |
| A1 | Excess shell area | (Et*t - F*tr)*d or 2*(Et*t-F*tr)*(t+tn) whichever larger | - | Available in shell | UG-37(a)(4) |
| A2 | Excess nozzle outer proj | 5*(tn-trn)*fr2*t or 2*(tn-trn)*(2.5*tn+te) | Outer limit | Projection | UG-40(b) |
| A3 | Nozzle inside proj | 5*t*ti*fr2 or 5*ti*ti*fr2 or 2*h*ti*fr2 | For set-through | Set-through | UG-40(c) |
| A4 | Fillet weld area | 0.5*leg^2 * fr2 | Weld area | Both sides | UG-37(a)(4) |
| A5 | Reinforcing pad | W*te*fr4 | Pad limits | Often added | UG-37(a)(4) |
| Exemptions from Reinforcement Check (UG-36(c)(3)) | |||||
| No reinforcement calculation required for openings if all are met: (1) NPS 3.5 or smaller in t<=3/8" shell; (2) NPS 2 or smaller in t>3/8" shell; (3) at least 2*D spacing between openings; (4) not in high stress location (near head-shell junction). Use UG-37 for all other cases. |
Source: Pressure_Vessel_Engineering_Curriculum_v1.xlsx · Sheet: Nozzles
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