Custom Pressure Vessel Heads and Tank Heads

Openex Metal Fabrication manufactures custom pressure vessel heads and tank heads, from one-piece formed heads to large segmental heads up to 24 m in diameter. We form ASME-code and non-code heads to your engineering drawings and project specifications. Also known as dished heads or vessel end closures, these components close the ends of cylindrical vessels in pressure equipment, storage tanks, boilers and process systems.

Our scope combines heavy forming, welding where the design permits, robotic edge trimming, heat treatment, machining, blasting and inspection. Each project is reviewed against the specified head profile, diameter, wall thickness, material grade, construction code and acceptance criteria.

Whether you need a 2:1 elliptical head, a torispherical head, a hemispherical head or a custom profile, the first step is to review your drawing and select the right manufacturing route.

Diameter

Up to 24 m

Segmental construction

Thickness

8 – 210 mm

Material dependent

PWHT furnace

35 × 11 × 12.5 m

Stress relieving

Codes

ASME & non-code

Per project scope

Types of Pressure Vessel Heads We Manufacture

Head geometry affects forming method, material requirements, dimensional control and the finished vessel design. Openex reviews the specified profile and tolerances before confirming production feasibility.

1. 1

   2:1 Semi-Elliptical Heads

   The most commonly specified vessel end. Final geometry and thickness depend on design pressure, temperature, material, and the governing design code.

2. 2

   Torispherical (Flanged & Dished) Heads

   Dished heads with a crown radius and knuckle radius, formed to the specified dimensions. Double-knuckle variants are also available.

3. 3

   Hemispherical Heads

   Spherical-profile heads for designs that call for hemispherical geometry. Very thin or very thick hemispheres are often best built as segmental heads.

4. 4

   Conical and Torispherical-Conical Heads

   Conical vessel ends and transitions made to the required angle, dimensions, and interface geometry, including tori-conical profiles.

5. 5

   Dished-Only, Toroidal and Custom Profiles

   Custom-formed ends produced from engineering drawings, subject to geometry, material, tooling, and process feasibility.

Segmental Tank Heads for Large and Difficult Geometries

Segmental (multi-piece) heads are a core part of our head work. They make very large diameters practical to form, transport and install, and they are often the only solution for thin or extremely thick hemispheres and multi-curvature structures.

• Heads are fabricated, trial fitted, tack welded, match-marked and knocked down for shipment, so they arrive ready for field or shop fit-up.
• Segments can be cold or hot formed from normalized or as-rolled plate.
• Edges are trimmed, tapered or beveled by robotic trimming for accurate, repeatable fit.
• Segmental construction is often the only practical route for very large diameters and for thin or extremely thick hemispheres and multi-curvature shapes.

Pressure Vessel Head Manufacturing Specifications

These are project-evaluation parameters, not a guarantee that every combination of diameter, thickness, material and profile can be built. Final limits are confirmed by our engineers against your drawing.

Need a maximum-size confirmation? Send the head drawing, material grade, thickness and applicable code. Openex can assess the proposed dimensions and manufacturing route before quotation.

Materials for Custom Tank Heads

Material selection should reflect design pressure, operating temperature, corrosion requirements, forming behavior and the governing vessel specification. Grade and delivery condition must be confirmed before production.

Applications of Pressure Vessel Heads

Custom-formed heads are used across many industrial vessels. The required geometry, material and inspection scope depend on process conditions and the design of the complete vessel.

• Pressure vessels and process equipment
• Storage tanks, propane and cryogenic vessels
• Oil and gas processing equipment
• Chemical and petrochemical plants
• Power generation, boilers and energy equipment
• Water treatment, pulp and paper, and transportation

Examples of Heads We Have Produced

A selection of completed head sizes. Ask for details on our more difficult projects, including very large and heavy-wall segmental heads.

• Ø5.0 m × 14 mm

  Tank head

• Ø5.5 m × 8 mm

  Nickel-base alloy

• Ø6.0 m × 16 mm

  Tank head

• Ø8.0 m × 32 mm

  Tank head

• Ø10 m × 18 mm

  Duplex stainless

How Pressure Vessel Heads Are Manufactured

Steps vary with head profile, thickness, material and code requirements. A typical project includes the following operations where applicable.

1. 1

   Drawing and Material Review

   Review head geometry, material specification, thickness, tolerances, construction code and inspection requirements. Confirm whether the design calls for a one-piece head or a segmental assembly.

2. 2

   Blank Preparation and Welding, If Required

   Prepare the plate blank to approved dimensions. Where plate splicing is permitted by the design, perform the specified welding and examinations before forming.

3. 3

   Dishing, Press Forming, and Flanging

   Form the blank or segments to the specified crown, knuckle, cone or other profile. Hot or cold forming is selected according to material, thickness, geometry and the approved procedure.

4. 4

   Trial Fit, Trimming and Match-Marking

   For segmental heads, segments are trial fitted, tack welded, match-marked and knocked down. Edges are robotically trimmed, tapered or beveled so the head is ready for fit-up.

5. 5

   Heat Treatment, Where Specified

   Apply the required heat-treatment cycle when called for by the material specification, forming procedure, construction code or project requirements. Record and verify process parameters.

6. 6

   Edge Preparation and Machining

   Machine specified edges, weld bevels and interfaces to the drawing. Groove preparations are used only where the joint design and welding procedure require them.

7. 7

   Inspection, Blasting and Documentation

   Complete agreed dimensional checks, material traceability review and specified NDT. Blast and prime where required, and supply the inspection records included in the contract scope.

Quality, Inspection, and Code Requirements

Head acceptance depends on the requirements for the complete vessel and its service. Before ordering, define the applicable code and edition, material traceability, forming and heat-treatment requirements, weld examination scope, dimensional tolerances and documentation package.

For projects specifying ASME Section VIII, PED/CE conformity or other regulatory requirements, confirm the exact certification scope and each party's responsibilities before production.

Why Work with Openex for Custom Tank Heads?

Large formed components need coordination across several manufacturing stages. Openex's wider fabrication and machining capability lets you assess a combined scope instead of sourcing every operation separately, subject to feasibility and the agreed supply scope.

• Drawing-based manufacturing: review of geometry, materials, tolerances and interface requirements.
• Segmental expertise: trial-fitted, match-marked heads with robotically trimmed edges, ready for fit-up.
• Integrated operations: forming, specified welding, heat treatment, machining, blasting and inspection coordinated where suitable.
• Engineering review before quotation: dimensions, process feasibility, code requirements and scope confirmed before you commit to delivery.

Related services: heavy press forming, heat treatment, and heavy CNC machining.

What to Send for a Pressure Vessel Head Quote

Include as much of the following as you can. If your design is still in development, start with the available drawing and preliminary specifications.

Frequently Asked Questions