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| Brand Name: | YUHONG |
| Model Number: | YGC-HX-001 |
| MOQ: | 1set |
| Price: | Negotiation |
| Delivery Time: | According to the quantity |
| Payment Terms: | T/T, L/C |
Industrial Fixed Tube Sheet Heat Exchanger | ASME Certified
What is Fixed Tube Sheet Heat Exchanger?
A fixed tube sheet heat exchanger is one of the most widely used types of shell-and-tube heat exchangers, renowned for its simplicity, robust construction, and cost-effectiveness. In this design, the tube bundle is permanently welded or expanded into a stationary tube sheet at both ends, which is then bolted to the shell. This configuration eliminates the need for floating heads or expansion joints in some cases, making it ideal for applications with moderate thermal stresses and clean operating fluids.
Key Componets:
Tube Sheets:
Thick, circular plates (often carbon steel, stainless steel, or titanium) that hold tubes in place.
Tubes are either welded, rolled, or expanded into the tube sheets to ensure a leak-proof seal.
Tubes:
Typically ¾" to 1.5" in diameter, made of materials like copper, stainless steel, titanium, or nickel alloys.
Arranged in triangular (30°/60°), square (90°), or rotated square layouts to balance heat transfer and cleaning access.
Shell:
Cylindrical vessel (carbon steel clad with corrosion-resistant materials) housing the tube bundle.
Baffles (segmental, helical, or rod-type) direct shell-side fluid flow to enhance turbulence and heat transfer.
Channels/Headers:
Distribute tube-side fluid into multiple passes (1-pass, 2-pass, etc.) to optimize velocity and residence time.
Working Principle
Fluids flow through two separate circuits:
Tube-side fluid: Passes through the tubes (1 to 8 passes, depending on design).
Shell-side fluid: Flows around the tubes, guided by baffles to maximize cross-flow contact.
Heat transfers across the tube walls via conduction and convection, with counterflow arrangements achieving the highest log mean temperature difference (LMTD).
Technical Specifications
Parameter | Typical Range |
|---|---|
Pressure | Shell-side: Up to 150 bar (2175 psi) |
Tube-side: Up to 300 bar (4350 psi) | |
Temperature | Standard: -20°C to 400°C (-4°F to 750°F) |
High-temp designs: Up to 600°C (1112°F) | |
Thermal Expansion | Requires expansion joints if ΔT > 50–100°C between shell/tube materials. |
Fouling Resistance | Tube pitch ≥ 1.25x tube diameter for cleanability. |
Surface Area | Compact designs: 5–500 m² (54–5380 ft²) |
Design Considerations
Thermal Stress Management:
Fixed tube sheets restrict differential thermal expansion between the shell and tubes.
Solutions:
Expansion joints: Bellows or flanged joints absorb axial expansion (common in steam applications).
Material matching: Use similar thermal expansion coefficients for shell/tube materials (e.g., carbon steel shell with carbon steel tubes).
Pressure Constraints:
Thickened tube sheets (up to 300 mm) for high-pressure applications.
Smaller tube diameters (e.g., ¾") improve pressure resistance.
Fouling Mitigation:
Smooth tubes with non-stick coatings (PTFE) for viscous fluids.
Chemical cleaning ports or CIP (Clean-in-Place) systems for maintenance.
Material Selection
Component | Common Materials | Use Case |
|---|---|---|
Tubes | SS 316L, Titanium, Cu-Ni, Inconel, Hastelloy | Corrosive/High-purity fluids (e.g., HCl, seawater). |
Shell | Carbon steel (clad with SS, rubber-lined) | Cost-sensitive, non-corrosive fluids. |
Baffles | SS 304, CS with epoxy coating | Erosion/corrosion resistance. |
Advantages
Low Cost: Fewer moving parts and simpler fabrication than floating head or U-tube designs.
Leak Resistance: Welded tube sheets minimize leakage risks.
Compactness: Ideal for high-pressure/temperature duties in limited space.
Limitations
Maintenance Challenges: Tube bundles cannot be removed; mechanical cleaning is difficult.
Thermal Stress Sensitivity: Unsuitable for large ΔT (>100°C) without expansion joints.
Fouling Prone: Narrow pitch designs risk clogging with dirty fluids.
Applications
Chemical/Petrochemical: Condensers, reboilers, and coolers for non-fouling fluids.
Power Generation: Feedwater heaters, lube oil coolers.
HVAC: Chillers and district heating systems.
Pharmaceuticals: Sterile heat exchange with double tube sheets to prevent cross-contamination.
Standards & Codes
TEMA (Tubular Exchanger Manufacturers Association): Class R (Refinery), C (General), or B (Chemical).
ASME BPVC Section VIII: Governs pressure vessel design.
ISO 16812: Specifies shell-and-tube heat exchanger requirements.
Conclusion
Fixed tube sheet heat exchangers strike a balance between simplicity, reliability, and cost, making them a go-to choice for moderate thermal and pressure conditions. Their design flexibility—through modifiers like baffle spacing, tube materials, and expansion joints—allows customization for diverse industries. However, careful consideration of fouling, thermal expansion, and maintenance access is critical during the design phase.
