Manufacturing a 24-Meter Multi-Piece Dished End
The Challenge: Scale and Site Logistics
An international EPC (Engineering, Procurement, and Construction) firm building a petrochemical storage terminal required a massive spherical dome for a field-erected pressure tank. At 24 meters (78+ feet) in diameter, the head was far too massive to transport via highway or ocean freight as a single unit.
The project demanded that the tank head be fabricated in distinct "crown" and "petal" segments. The extreme challenge lay in dimensional control: if the petals were formed with even a few millimeters of variance at our facility, the field-welders at the construction site would spend weeks grinding and adjusting panels, destroying the project's timeline and budget.
The Openex Manufacturing Solution
By utilizing our 180-acre facility space, our engineers proposed a completely managed manufacturing and "mock-assembly" workflow to guarantee flawless on-site integration.
The 35mm thick SA516-70 carbon steel plates were precisely cut on our massive gantry plasma tables. Each individual segment was then pressed using our custom spherical forming dies to ensure an exact radius match without localized material thinning.
Because the final welding would occur on the job site, Openex used 5-axis robots to perfectly prep the weld-seam edges of every single panel with a complex J-bevel, drastically minimizing the weld volume and heat required during field installation.
Before shipment, Openex executed a complete "knock-down" trial fitment. We temporarily assembled the entire 24m dome on our factory floor. Utilizing large-scale 3D Laser Trackers, our metrology team mapped the geometry, applied precise match-marking stamps across the seams, and confirmed zero-gap alignment.
Project Specifications
| Attribute | Project Details |
|---|---|
| Final Geometry | Hemispherical Segmented Dished End (Multi-piece Petal & Crown) |
| Dimensions | Outside Diameter (O.D.): 24 Meters | Plate Thickness: 35mm |
| Material Composition | SA516 Grade 70 (Normalized Pressure Vessel Steel) |
| Value Add Services | Die Pressing, Edge Bevelling, 3D Metrology Mapping, Knockdown Crating |
The Outcome
The multi-piece dished end arrived at the client's petrochemical facility match-marked and ready for installation. Because the fitment was 100% verified prior to shipping, the on-site contractors required zero rework or panel grinding, slicing nearly a month off their planned tank erection schedule and massively decreasing site welding costs.