Yuhong Group Co., Ltd. manufactures this heavy-duty fixed tubesheet shell and tube heat exchanger to ASME Section VIII Division 1, specifically designed for cooling process gas (H2S content ≥ 90%) and sulfur vapor condensation after a waste heat boiler. The unit features a carbon steel pressure boundary, utilizing SA-516 Gr. 60N normalized plate for the shell and SA-179 seamless tubes for the heat transfer surface. The equipment is configured as a TEMA NXN type with a single pass on both sides, incorporating a shell expansion joint to absorb differential thermal expansion. With a heat transfer area of 131 m², 150 tubes at a 7300 mm length, and a post-weld heat treatment (PWHT) requirement, this exchanger is engineered for high-integrity chemical and refinery service.
| Component | Grade / Specification | Typical service condition |
|---|---|---|
| Shell & Reinforcing pads | SA 516 Gr. 60N (Normalized plate) | Carbon steel shell for cond/BFW/steam duty; corrosion allowance 3.2 mm |
| Tube sheets | SA 765 Gr. 2 | Forged carbon steel tubesheets for high-pressure joint integrity |
| Baffles & Connection pipes (N1, N2, Manways) | SA 516 Gr. 60N | Internal flow distribution and structural support |
| Tie rods | SA 36 | Bundle spacing and support |
| Grade | Specification | Heat Treatment |
|---|---|---|
| SA 179 | Seamless cold-drawn low-carbon steel | Not less 650℃ after the final cold draw pass |
| Component | Grade / Specification | Application |
|---|---|---|
| Nozzle flanges | SA 350 LF2 CL.1 | Low-temperature impact-tested flanges for inlet/outlet |
| Casing flanges | SA 765 Gr. 2 | Main shell flange connections |
| Case flange gasket | Spiral wound (316L + Graphite, 1002-958-4.0/660.0) | High-temperature and H2S-resistant sealing |
| Nozzle flange gasket | Spiral wound (316L + Graphite + CS Outer Ring) | Nozzle sealing with outer ring for blowout prevention |
| Grade | Specification | Application |
|---|---|---|
| Bolts / Nuts | SA 193 Gr. B7M / SA 194 Gr. 2HM | High-strength bolting for flange closures |
| Parameter | Specification |
|---|---|
| Design standard | ASME Section VIII Div. 1 (with PWHT) |
| TEMA Type | NXN (Fixed tubesheet with shell expansion joint) |
| Design pressure | Shell side: 0.59 MPa; Tube side: 0.39 MPa |
| Design temperature | Shell side: -35°C / +245°C; Tube side: -35°C / +295°C |
| Hydrotest pressure | Shell side: 1.59 MPa; Tube side: 0.55 MPa |
| Heat transfer area | 131 m² |
| Tube quantity & length | 150 tubes; 7300 mm length; 30° triangular pitch |
| Shell inside diameter | 800 mm |
| Corrosion allowance | Shell/Tubesheets: 3.2 mm; Tubes: 0 mm |
| Overall dimensions | 9771 mm (L) × 1874 mm (W) × 2574 mm (H) |
| Installation & Seismic | Outdoor installation; Seismic load 6 scores |
The exchanger is designed and fabricated to ASME Section VIII Division 1, with the following quality control scope:
Post-Weld Heat Treatment (PWHT): Yes, applied to relieve residual stresses in the pressure boundary.
Non-destructive examination: Radiography (RT), penetrant testing (PT), ultrasonic testing (UT), and positive material identification (PMI) as specified on the drawing.
Hydrostatic testing: Shell side tested at 1.59 MPa and tube side at 0.55 MPa.
Refractory lining: Inlet channel and lower channel are lined with refractory materials (50 mm and 136 mm respectively) to manage high-temperature process gas.
Surface protection: External surface prepared to Sa 2.5 and painted for outdoor installation.
Exchanger body: Secured in a plywood case or iron-frame crate, considering the overall length of 9771 mm.
Opening protection: All flanged openings (including N1, N2 and manways) sealed with wooden or plastic blind covers to prevent moisture ingress.
Internal preservation: Desiccant bags applied to prevent corrosion during transit.
Documentation: Packing list, material certificates (EN 10204 3.1/3.2), PWHT charts, and hydrotest reports placed in a watertight document holder inside the crate.
Why is an SA 765 Gr. 2 tube sheet used instead of standard carbon steel plate?
SA 765 Gr. 2 is a forged carbon steel specification, offering better structural integrity and thickness control for the tubesheet.
This ensures robust tube-to-tubesheet joint strength (strength weld & expanding with 2 grooves) under the specified design pressure and thermal cycles.
What is the function of the shell expansion joint?
At a tube-side design temperature of 295°C and shell-side 245°C, the shell and the 7300 mm tube bundle expand at different rates.
The expansion joint absorbs this differential movement, reducing thermal stress on the fixed tubesheets and tube joints.
What are the commercial terms?
MOQ: 1 set per configuration.
Incoterms: FOB, FCA, CIF, or EXW, quoted against the agreed shipment mode and destination.
Lead time: approximately 90–150 days after drawing approval, based on the ASME scope, refractory lining, and material procurement.
What information is needed for a firm quotation?
Fluid names, flow rates, and allowable pressure drop for both sides.
Required TEMA designation, connection sizes, and NDT scope.
Destination port and required Incoterm.
For datasheets, drawings, or an ASME Section VIII Div. 1-based quotation, please write to vladimir@steelseamlesspipe.com
