Pressure Vessel Sizing Calculator — ASME Section VIII Div. 1

1Vessel Configuration

Type & shell arrangement

Vessel Type

Cylindrical Spherical (Horton Sphere)

Shell Configuration

Single Diameter Two Diameters + Cone

Configuration Notes

Standard single-diameter cylindrical vessel with formed heads at each end.

2Design Basis & Material

ASME BPVC VIII-1 · UG-27 / UG-32

Internal Design Pressure MPa

Design Temperature °C

Diameter Basis

ID OD

Diameter (as selected) mm

Tan-to-Tan Shell Length mm

Corrosion Allowance mm

Joint Efficiency, E

Vessel Orientation

Vertical Horizontal

Shell / Head Material (ASME)

Base value shown is a typical low-temperature (~100°F/38°C) allowable stress per Section II-D. S below is then auto-adjusted for Design Temperature using an approximate reduction curve — verify the exact tabulated value before final design.

Allowable Stress, S MPa

Auto-adjusted for Design Temperature — editable; select Custom to fully override.

Material Density, ρ kg/m³

Design MDMT °C

Reference only — impact test exemption (UCS-66) not evaluated by this tool.

Recommended Nozzle/Flange Rating ASME B16.5 (approx.)

Minimum Class—

at Design Conditions—

3Heads & Nominal Thickness

UG-32 formed heads

Head Type

Number of Heads

1 (open end) 2

Straight Flange, SF mm

Shell Nominal Thickness (as-built) mm

Used for MAWP back-calculation and weight.

Head Nominal Thickness (as-built) mm

Support Type

Vertical vessels: skirt or legs. Horizontal vessels: saddles (fixed).

Number of Legs

Support Height mm

4Nozzle Schedule

0 nozzles

Tag	Service	NPS	Sched.	Neck Type	Location	Orientation	Projection (mm/in)	Sketch Pos % (shell only)	Side (sketch)	Selected	Req. Wall t (design P)	Check

Nozzle-to-shell reinforcement per UG-37 is not evaluated — verify area replacement separately.

Head 1 = bottom head (vertical) / left head (horizontal) · Head 2 = top head (vertical) / right head (horizontal). Sketch Side A/B = Left/Right for vertical vessels, Top/Bottom for horizontal vessels (front view).

Sched. "Auto" picks the lightest of STD/XS/Sch 160 that meets the required wall at design pressure — "Selected" shows which one was used. Neck Type: WN = Weld Neck · LWN = Long Weld Neck (integral extended neck, e.g. through insulation) · SRN = Self-Reinforced Nozzle (heavy wall sized to avoid a separate reinforcing pad — this tool checks pressure-design wall only; UG-37 area replacement must still be verified).

5Vessel Sketch

Vertical · Skirt

Schematic only — not to scale. Updates live as design basis, head type, supports and nozzle schedule change.