Ellipsoidal
Torispherical
| Drawing input | Ellipsoidal profile | Torispherical profile |
|---|---|---|
| Crown | Elliptical profile; identify the intended ratio | Spherical crown; identify crown radius |
| Transition | Define the actual profile and flange transition | Identify knuckle radius and flange transition |
| Depth & flange | State crown depth, overall height and straight flange separately | State crown depth, overall height and straight flange separately |
| Thickness | State nominal or formed-minimum basis | State nominal or formed-minimum basis |
| Design & manufacture | Review actual material, conditions, standards and forming requirement | Review actual material, conditions, standards and forming requirement |
These are specification inputs. The comparison does not establish a pressure rating, a material saving or a universally preferred design.
Two different crown profiles
An ellipsoidal head follows an elliptical profile. A torispherical profile combines a crown with a knuckle transition. Their dimensional descriptions should not be treated as interchangeable.
Compare like-for-like dimensions
A useful comparison begins with clearly stated design inputs and measurement bases.
- The same ID or OD basis and units.
- Defined profile ratio for the ellipsoidal option.
- Crown and knuckle radii for the torispherical option.
- Depth, straight flange and thickness basis for each.
Bring the material and process into the comparison
Manufacturing requirements depend on the material, geometry, thickness and subsequent processing. A shape comparison alone does not establish which option is suitable or less costly for a particular project.
Confirm the project decision
Record the applicable geometry standard and design requirements, then ask the responsible engineer to confirm the selected profile. Use the relevant product collection to prepare the corresponding enquiry.