Titanium Pressure Vessel Head Types and Selection
Titanium pressure-vessel head selection starts with the approved vessel design and finished profile, not appearance alone. Ellipsoidal, torispherical and hemispherical heads differ in geometry, depth, forming demand, thickness distribution and equipment envelope.
Head Type Comparison
| Head form | Geometry | Purchasing focus |
|---|---|---|
| 2:1 ellipsoidal | Elliptical profile with defined axes | Inside profile, straight flange and minimum thickness |
| Torispherical | Crown and knuckle radii | Code radii, knuckle thinning and templates |
| Hemispherical | Half-sphere pressure surface | Depth, forming route, handling and fit-up |
Finished Thickness and Profile
Nominal starting plate does not prove finished-head thickness. Forming redistributes material, particularly near the knuckle. State minimum finished thickness, thinning allowance, measurement grid, profile tolerance, diameter datum and straight-flange requirements.
Material, Forming and Welding
Define titanium grade, plate standard and condition, forming route, segment/weld policy, heat treatment or stress-relief requirements if applicable, weld edge and surface condition. The responsible design authority controls code compliance and allowable construction.
Inspection and Documentation
State dimensional/profile inspection, thickness mapping, visual/PT/RT/UT requirements as applicable, material records, weld records, MTC, heat traceability and third-party witness. Inspection stages should reflect forming, welding and final condition.
Quote From the Finished-Head Definition
Review Titanium Pressure Vessel Heads and send the approved profile, thickness map, edge and inspection plan.
RFQ Checklist
- Design code, approved drawing and head type
- Grade, plate specification and condition
- ID/OD datum, profile and straight flange
- Starting and minimum finished thickness
- Forming, welding, NDE and documentation
FAQ
Is a dished vessel head the same as a pipe cap?
No. A vessel head is a pressure-boundary component governed by the vessel design and inspection plan.
Can starting plate thickness be used as finished thickness?
No. Finished minimum thickness must be verified after forming.
Related Reading
Specify Forged Nozzles · Plate Thickness and Flatness · Tolerance and Inspection