ASME Section VIII Div. 1 TEMA Class BKU Heat Exchanger Shell and Tube Heat Exchanger
Reboiler kettle-type shell and tube heat exchanger designed for CO2 removal plants in direct reduced iron (DRI) facilities. Manufactured as an ASME Section VIII Division 1 stamped TEMA heat exchanger, the shell side processes MDEA stripping solution while low-pressure steam flows through the tube side. The unit features an expanded kettle shell cross-section (1,649 mm ID / 2,730 mm ID) with an internal overflow weir plate to facilitate vapor-liquid separation across a 670 m² active heating surface.
Note: High-density finned tube bundle configurations can be integrated into specialized gas-phase recovery circuits requiring enlarged external heat transfer surface areas.
Core Components & Material Specifications
| Component Part | Material Grade / Standard Specification | ASME / ASTM Code |
| Pressure Shell & Transition Cone |
SA-516 Grade 70 Carbon Steel Plate / SA-106 Grade B Pipe |
ASME SA-516 / SA-106 |
| Channel / Channel Cover |
SA-516 Grade 70 Carbon Steel Plate |
ASME SA-516 Grade 70 |
| U-Bend Heat Transfer Tubes |
SA-213 TP316L Seamless Stainless Steel (25.4 mm OD x 2.11 mm MW) |
ASME SA-213 Grade TP316L |
| Stationary Tubesheet |
SA-516 Grade 70 Carbon Steel Plate with SS 316L Overlay |
ASME SA-516 / SA-240 |
| Baffles & Support Plates |
Carbon Steel / SS 304 Baffle Structural Supports |
ASME Sec. II / TEMA Class BKU |
| External Bolting (Studs / Nuts) |
SA-193 Grade B7 Galvanized Studs / SA-194 Grade 2H Nuts |
ASME SA-193 / SA-194 |
| Internal Gaskets |
Double Jacketed Metal Gasket SS 304 with Flexible Graphite Fill |
ASME B16.20 |
| Process Nozzles & Flanges |
Carbon Steel SA-105 / SA-106 Grade B (NPS 18, 24, 30) |
ASME B16.5 / ASME B16.47 |
Core Technical & Fabrication Features
ASME Code Stamped Kettle Construction: Built to ASME Section VIII Division 1 and TEMA Class BKU specifications, featuring an asymmetrical kettle shell geometry to accommodate phase-change vapor disengagement.
U-Tube Matrix Layout: Incorporates 25.4 mm OD SA-213 TP316L seamless tubes bent into a U-tube configuration to allow unrestricted thermal expansion during thermal cycles.
Internal Weir Plate Disengagement: Integrates a full-height internal overflow weir plate dividing the boiling zone from the liquid draw-off compartment.
Tube-to-Tubesheet Joints: Tubes are expanded and strength-welded to the SS 316L cladded face of the SA-516 Grade 70 tubesheet.
Post-Weld Heat Treatment (PWHT): Shell-side carbon steel pressure-retaining weldments undergo stress relief heat treatment per ASME Section VIII Division 1 rules.
Quality Assurance & Testing Specifications (QA/QC Specification)
Radiographic Examination (RT): Spot radiographic testing (RT-3 / ASME UW-11) conducted on longitudinal and circumferential main shell seam welds.
Liquid Penetrant Examination (PT): 100% liquid penetrant testing executed on tube-to-tubesheet strength welds and SS 316L overlay surfaces.
Hydrostatic Pressure Test: Shop hydrostatic pressure test performed in horizontal position at 10.5 bar(g) on the tube side and 5.3 bar(g) on the shell side using treated water.
Surface Preparation & Coating: External carbon steel surfaces blast cleaned to ISO 8501-1 Sa 2.5 (Near-White Metal) and coated with high-temperature primer and topcoat.
Material Certification: All pressure-retaining components, flanges, and structural attachments furnished with EN 10204 Type 3.1 material test certificates.
International Logistics & Market Support
Internal Nitrogen Purge: Shell and tube chambers thoroughly dried after hydrotest and sealed with a positive pressure nitrogen blanket for overseas transit.
Structural Support Saddle Interface: Outfitted with dual heavy-duty steel saddles featuring 12.7 mm base plates, sliding slots (38×76 mm), and 3 mm SS 304 isolation plates under sliding pads.
Export Compliance Documentation: Delivered with ASME Form U-1A Manufacturer's Data Report, complete MTR dossiers per EN 10204 3.1, NDE inspection logs, and pre-cleared documentation for North African and Middle Eastern customs release.
