ASME Pressure Vessel Heads & Shell and Tube Heat Exchanger Closures
Yuhong Group Co., Ltd. is a certified manufacturer and exporter of high-precision pressure vessel heads and custom closures designed for industrial process equipment. Serving global industries through www.tema-heatexchanger.com, we supply a complete range of cold-formed and hot-stamped dished heads engineered to perform seamlessly with high-pressure shell and tube heat exchanger systems, boilers, reactors, and air cooling units.
Whether you are retrofitting an existing shell & tube heat exchanger, replacing a channel head enclosure, or sourcing complete internal components—including a precision-machined heat exchanger tubesheet, custom u tube bundle, or heavy-duty finned tube bundle—Yuhong Group offers custom-engineered ASME Section VIII Div. 1 compliant solutions.
Product Types & Structural Configurations
We manufacture dished heads in a wide variety of geometry profiles to suit distinct pressure ratings, wall thickness demands, and space limitations:
- 2:1 Semi-Elliptical Heads (Ellipsoidal Heads): The most widely used closure for medium-to-high pressure vessels and shell and tube heat exchanger channels, offering superior stress distribution and economic material utilization.
- Hemispherical Heads: Engineered for extreme high-pressure applications where wall thickness can be reduced while maintaining structural integrity.
- Torispherical Heads (Flanged and Dished / F&D): Cost-effective closures suitable for lower to moderate operating pressures.
- Flat Heads & Forged Cover Plates: Heavy forged discs precision-machined for removable channel covers and high-pressure plug headers.
- Conical Reducers & Transition Sections: Custom cone sections used for diameter transitions in specialized heat exchange vessels.
Materials & Manufacturing Standards
To withstand severe mechanical fatigue, high temperatures, and aggressive corrosive media, Yuhong Group supplies heads manufactured from certified plate and forging stocks:
| Material Category | Grade Specifications | Applicable Standards |
|---|
| Stainless Steel | SA240 304/304L, SA240 316/316L, SA240 321, SA240 317L | ASME SA240 / ASTM A240 |
| Duplex & Super Duplex | UNS S31803 (2205), UNS S32750 (2507), UNS S32760 | ASME SA240 / EN 10028-7 |
| High-Nickel Alloys | Inconel 600/625, Incoloy 800/825, Monel 400, Hastelloy C276 | ASME SB168 / SB443 / SB575 |
| Carbon & Alloy Steel | SA516 Gr.60/70, SA387 Gr.11/Gr.22 (Chrome-Moly) | ASME SA516 / SA387 |
Integrated Components & Heat Exchanger Internal Assemblies
A quality dished head is only one part of an efficient thermal processing system. Yuhong Group supplies fully integrated component packages to simplify your procurement and turnaround maintenance:
| Component Part | Role in Heat Exchanger System | Technical Highlight |
|---|
| Heat Exchanger Tubesheet | Welded or bolted directly to the head/shell junction to support process tubes. | Precision CNC drilled and grooved for high-integrity tube-to-tubesheet joints. |
| U Tube Bundle / Straight Tube Bundle | Inserts into the shell body sealed by the head channel. | Hydrostatically tested and stress-relieved tube bundles for fast field turnaround. |
| Pass Partition Plates | Welded inside the channel head to direct multi-pass fluid flow. | Custom fitted to match head contours and eliminate inter-pass fluid bypass. |
| Finned Tube Bundle Assemblies | Core thermal transfer matrix for process air cooling. | High-surface area extruded or embedded finned tubes engineered for zero air-side resistance loss. |
| Flanges & Nozzles | Welded to the head shell for piping connections and instrument ports. | Forged ANSI / ASME B16.5 flanges rated up to Class 2500. |
Key Advantages & Application Suitability
- Precision Edge Beveling: All heads feature CNC-machined welding bevels (V, U, or compound bevels) to ensure full penetration welds and effortless fit-up during shell assembly.
- Post-Forming Heat Treatment: Solution annealing (for stainless/duplex grades) or stress relieving is performed in-house to eliminate cold-work residual stresses and restore optimal corrosion resistance.
- Severe Duty Capability: Ideal for heavy refining, petrochemical processing, offshore platforms, and power generation units handling lethal or highly acidic fluids.
- 100% Quality Assurance: Certified with complete Mill Test Reports (MTRs to EN 10204 3.1/3.2), RT/UT weld seams inspection, and 3D dimensional laser scanning.
Engineering Knowledge: Essential Parameters for Ordering Vessel Heads
When sourcing or replacing a shell and tube heat exchanger head or vessel closure, technical engineers and procurement managers should verify the following key factors:
- Inside Diameter (ID) vs. Outside Diameter (OD) Specification: Always specify whether dimensions refer to ID or OD, as hot/cold forming tolerances can affect the final joint fit to the shell cylinder.
- Minimum Wall Thickness After Forming: Forming processes cause thinning at the crown and knuckle radii. Always calculate required nominal plate thickness based on post-forming minimum thickness requirements.
- Heat Treatment Requirements: Stainless steel heads (e.g., SA240 321/316L) subjected to severe forming require full solution heat treatment to prevent intergranular corrosion in service.
Request a Technical Evaluation & Quote
Need a custom-formed ASME elliptical head, a replacement tube bundle, or a precision-machined heat exchanger tubesheet?
Contact the Yuhong Group engineering team today for rapid pricing and technical consultation:
- Email: jimmy@steelseamlesspipe.com
- Official Website: www.tema-heatexchanger.com
- Company: Yuhong Group Co., Ltd.
