Pressure and thickness.
A controlled starting point.
Preliminary internal-pressure thickness calculation for cylindrical shells, 2:1 ellipsoidal heads, hemispherical heads and conical sections. Request a quotation with your dimensions and process details.
Enter a verified allowable stress S and its source to calculate.
Vacuum and external pressure are not calculated by this tool. Results apply only to internal pressure; external-pressure and buckling checks are required separately.
Calculated thickness excludes general minimum thickness, head-forming thinning, other loads and fabrication requirements. The preliminary pressure limit is not an approved MAWP for the complete vessel.
Calculation basis and limitations
Basic ASME VIII Division 1 UG-27 / UG-32 internal-pressure equations are used. The user supplies S and weld efficiency. The calculation uses the corroded inside diameter D + 2CA; for existing plate it uses t × (1 − tolerance/100) − CA. If the entered thickness is an already measured minimum, enter zero tolerance to avoid deducting tolerance twice.
The pressure input is the internal pressure at the component being checked; static liquid head must be added by the user when applicable. Head thickness should be treated as the minimum after forming. Internal depth D/4 is assumed for a 2:1 ellipsoidal head. Cone thickness is evaluated at the large diameter and normal to the surface; junction reinforcement is not calculated.
This version does not cover torispherical heads, vacuum, hydrostatic-test pressure, nozzle reinforcement, supports, wind or seismic loads, fatigue, creep, minimum design metal temperature or complete code-compliance checks. The result is preliminary and is not a manufacturing approval or certificate of conformity.
Reference: ASME BPVC VIII-1 UG-27 and UG-32. Final engineering verification must use the project standard and applicable edition.