ASME SA336 Gr.F5N Heat Exchanger Tube Sheet Manufacturer & Supplier
Yuhong Group Co., Ltd. supplies ASME-coded heat exchanger components including tube sheets, U-tubes, heat exchanger tubes, finned tubes, tube bundles, baffle plates, channel covers, and pressure vessels. This product overview focuses on the ASME SA336 Gr.F5N forged tube sheet—a critical component for shell-and-tube heat exchangers operating in elevated temperature and pressure services.
Product Overview
ASME SA336 Gr.F5N forged chrome-moly tube sheet for shell-and-tube heat exchangers, pressure vessels, and boilers in high-temperature (up to 600°C / 1112°F) and high-pressure service. Manufactured to ASME Section VIII Div.1 and TEMA standards, available in custom diameters up to 8 meters with CNC-drilled hole patterns.
It serves as the structural anchor that secures the tube bundle in fixed alignment while maintaining positive separation between shell-side and tube-side fluids. As a forged component rather than rolled plate, the SA336 F5N tube sheet offers refined grain structure and improved mechanical property consistency—particularly critical when the tube sheet must withstand differential thermal expansion between tubes and shell, cyclic pressure loading, and aggressive process media.
The material designation follows ASME SA336 / SA336M, the standard specification for alloy steel forgings for pressure and high-temperature parts.
Material Specifications & Chemical Composition
The ASME SA336 Gr.F5N tube sheet is forged from chromium-molybdenum alloy steel with the following specified composition:
| Element |
Composition (%) |
| Carbon (C) |
≤ 0.15 |
| Chromium (Cr) |
4.0 - 6.0 |
| Manganese (Mn) |
0.30 - 0.60 |
| Molybdenum (Mo) |
0.45 - 0.65 |
| Silicon (Si) |
≤ 0.50 |
| Phosphorus (P) |
≤ 0.025 |
| Sulfur (S) |
≤ 0.025 |
The 4.0-6.0% chromium content provides oxidation and corrosion resistance at elevated temperatures, while molybdenum enhances creep strength and resistance to hydrogen attack.
Mechanical Properties
| Property |
Value |
| Tensile Strength |
415 - 585 MPa (60 - 85 ksi) |
| Yield Strength (Rp0.2) |
≥ 250 MPa (36 ksi) |
| Elongation |
≥ 20% |
| Modulus of Elasticity |
220 - 228 GPa (31.9 - 33.1 × 10³ ksi) |
| Density |
7.67 - 7.86 kg/dm³ |
Testing & Inspection Requirements
Each ASME SA336 Gr.F5N tube sheet is subject to the following inspection and testing protocols per ASME Section VIII and TEMA requirements:
| Test / Inspection |
Standard / Method |
Acceptance Criteria |
| Chemical Analysis |
ASTM E415 / Optical Emission |
Per SA336 composition table |
| Tensile Test |
ASTM E8 / E21 |
415-585 MPa UTS, ≥250 MPa YS |
| Hardness Test |
Brinell or Rockwell |
Per drawing / customer spec |
| Ultrasonic Examination |
ASTM A388 / SA388 |
Per ASME Section VIII App. 12 |
| Liquid Penetrant Examination |
ASTM E165 |
Per ASME Section VIII |
| Dimensional Inspection |
CMM / Bore Gauge |
Per TEMA / customer drawing |
| Positive Material Identification (PMI) |
XRF |
100% verification |
| Hydrostatic Test (when required) |
ASME Section VIII |
Per design pressure |
Applications
ASME SA336 Gr.F5N tube sheets are specified for shell-and-tube heat exchangers, waste heat boilers, steam generators, and pressure vessels in the following industries:
- Petrochemical & Refining: Hydroprocessing units, catalytic reforming, delayed cokers, and crude unit preheat trains
- Power Generation: HRSG evaporator sections, feedwater heaters, and nuclear conventional island heat exchangers
- Oil & Gas: Gas processing plants, amine treaters, and glycol dehydration units
- Chemical Processing: High-temperature reactors, synthesis gas coolers, and sulfuric acid plants
- Steel & Metallurgy: Waste heat recovery systems
The Gr.F5N grade is specifically suited for service temperatures up to 600°C (1112°F), where carbon steel grades lose strength and creep resistance becomes a design-limiting factor.
Technical Advantages & Customization
Forged vs. Rolled Plate: The forging process refines the internal grain structure and eliminates porosity, delivering more consistent mechanical properties through the full thickness—particularly important for thick tube sheets where plate laminations could compromise pressure retention.
Precision Machining: CNC drilling and boring operations achieve hole position accuracy within ±0.01mm and surface finish down to Ra 0.6μm in the bore. Grooving options (single or multiple grooves per tube hole) increase tube-to-tubesheet joint strength for expanded or welded tube connections.
Custom Capabilities:
- Maximum forging diameter: up to 8 meters
- Maximum forging weight: up to 100 metric tons
- Thickness: per customer drawing
- Hole patterns: triangular, square, or rotated square pitch per TEMA
- Edge preparation: beveled, threaded, or counterbored per design
Traceability: Full material traceability from melt to finished product, with MTR (Mill Test Report) documentation per EN 10204 Type 3.1 or 3.2.
FAQ / Common Technical Considerations
Q: What is the difference between ASME SA336 F5 and F5N?
The "N" suffix indicates the normalized heat treatment condition. Normalizing refines the grain structure and produces more consistent mechanical properties compared to the as-forged (F5) condition. For pressure-containing tube sheets, the normalized condition is typically specified to ensure uniform properties through heavy sections.
Q: Can SA336 F5N tube sheets be welded to carbon steel shells?
Yes, but weld procedure qualification is required. The chromium content (4.0-6.0%) necessitates preheat and post-weld heat treatment (PWHT) to avoid hydrogen cracking. Transition joints or buttering techniques may be specified depending on the shell material.
Q: What is the maximum design temperature for SA336 F5N?
The grade is suitable for service up to approximately 600°C (1112°F), limited by oxidation resistance and creep strength. For specific design temperatures, ASME Section VIII Div.1 allowable stress tables should be consulted.
Q: How is tube hole spacing determined?
Tube pitch is calculated per TEMA standards based on tube OD, ligament efficiency, and required pressure containment. Minimum ligament thickness must satisfy both TEMA and ASME Section VIII requirements for the design pressure and temperature.
Q: What NDE methods are required for ASME tube sheets?
ASME Section VIII requires ultrasonic examination of the forging prior to machining (per SA388) and liquid penetrant or magnetic particle examination of finished machined surfaces. Additional requirements may apply per the user's design specification.
