Stainless Steel Stacked Shell and Tube Heat Exchanger | Compact Multi-Shell Process Exchangers & Replacement Cores
Yuhong Group Co., Ltd. operates direct seamless tubing mills and heavy pressure vessel manufacturing facilities, delivering fully traceable heat transfer equipment and replacement internals. We specialize in engineering and building custom stacked shell and tube heat exchanger units, removable tube bundle assemblies, extended surface finned tube bundle cores, and heavy forged heat exchanger tubesheet plates for high-duty fluid processing facilities.
Operating under ISO 9001 and ASME quality systems, Yuhong Group manages raw metallurgy from tube cold-drawing to final pressure vessel assembly. Our stacked shell & tube heat exchanger configurations provide high thermal efficiency for refinery, petrochemical, and natural gas treatment plants operating under restricted footprint constraints.
Standard single-shell exchangers frequently fail to achieve required heat recovery rates in process loops characterized by severe temperature cross conditions (where the cold fluid outlet temperature exceeds the hot fluid outlet temperature). Stacking shells in series simulates true counter-current fluid flow while preventing thermal expansion damage.
Footprint Efficiency: Reduces horizontal plot area requirements by up to 50% through vertical stacking using structural C-channel saddles and inter-connecting nozzle flanges.
Pressure & Temperature Range: Engineered to operate under design pressures from vacuum up to 15 MPa (2,175 psi) and operating temperatures ranging from -196℃ (cryogenic LNG service) to 550℃.
Corrosion Allowance & Tolerances: Shell wall thickness tolerances conform strictly to ASME Section VIII Division 1. Tubesheet hole diameters and groove serrations are CNC-machined within ±0.02 mm of TEMA Class R requirements.
Yuhong Group fabricates stacked thermal units across standard TEMA mechanical configurations matching exact plant layout requirements:
Removable U Tube Bundle Stacked Exchangers (TEMA ABU / CFU): Features a floating u tube bundle core anchored to a single tubesheet. Accommodates extreme differential thermal expansion between shell and tube passes without generating mechanical strain on joint welds.
Floating Head Stacked Exchangers (TEMA AES / BES): Features a stationary tubesheet and an internal floating head cover. Permits complete bundle withdrawal for high-pressure hydro-jetting of shell-side foulants.
Fixed Tubesheet Stacked Exchangers (TEMA BEM / AEM): Rigid dual-tubesheet architecture suited for clean process media or steady-state thermal duties.
Austenitic Stainless Steels: ASTM A240 / A213 304/304L, 316/316L, 321, 347H.
Duplex & Super Duplex Steels: UNS S31803 / S32205 (Duplex 2205), UNS S32750 (Super Duplex 2507) for high-chloride fluids and sour gas (H2S) service.
High-Nickel Alloys: Monel 400 (UNS N04400), Inconel 625 (UNS N06625), Hastelloy C276.
| Core Component | Engineering Manufacturing Standards | Technical Function in Stacked Heat Exchangers |
| Heat Exchanger Tubesheet |
Heavy Forged SA182 F316L / F51; CNC Drilled with Double Serrated Grooves |
Acts as the main pressure barrier separating tube and shell fluids; secures tube ends under high differential pressures. |
| Heat Transfer Tubes |
Plain Seamless, Low-Finned, or Bent u tube bundle Stainless Tubing |
Conducts thermal energy between isolated process media; cold-drawn with controlled OD and wall thickness. |
| Baffles & Support Plates |
Single-Segmental, Double-Segmental, or NTIW Baffles in SS316L / Carbon Steel |
Directs shell-side flow perpendicular to the tube array to promote turbulence while supporting tubes against vibration. |
| Inter-Connecting Nozzles |
Forged ANSI B16.5 Flanges with Heavy-Wall Seamless Pipe Connections |
Routes process fluids between upper and lower stacked shells without external pressure drops or joint leakage. |
| Support Saddles & Stacking Clips |
Structural Steel Welded Saddles Engineered for Seismic & Thermal Loads |
Securely mounts the upper shell onto the lower vessel, allowing longitudinal thermal growth during operation. |
Precision CNC Machining & Serration: All heat exchanger tubesheet plates undergo deep-hole drilling on multi-axis CNC machines. Double serrated grooves (0.4 mm depth) provide high mechanical pull-out strength during tube expansion.
Automated Orbital Welding & Expansion: Tube-to-tubesheet joints are strength-welded using automated GTAW (TIG) processes, followed by torque-controlled hydraulic expansion to eliminate crevice corrosion gaps.
Solution Annealing for Cold Bends: U-bend zones on all u tube bundle sets undergo post-bend solution heat treatment (1,040℃--1,100℃) to restore passivation layers and eliminate residual tensile stress.
Factory NDT Testing: 100% Non-Destructive Examination including Hydrostatic Pressure Testing (1.5× design pressure), Eddy Current Testing (ET) on tubing, Radiographic Testing (RT) on pressure seams, Liquid Penetrant Testing (PT), and PMI material verification.
Managing Inter-Shell Thermal Stress: In stacked installations operating above 200℃, differential thermal expansion between top and bottom shells generates bending moments on interconnecting nozzles. Utilizing floating head internals or slotted saddle bolt holes absorbs thermal movement safely.
Tube Pitch & Hydro-Jetting Clearances: When processing heavy hydrocarbons, selecting a 90° or 45° square tube pitch layout provides straight cleaning lanes for high-pressure hydro-blasting during plant turnarounds. A 30° triangular pitch is recommended for clean fluids to maximize heat transfer surface density.
Baffle-to-Shell Bypass Prevention: Outer tube limit (OTL) clearances must strictly adhere to TEMA Class R specs. Excessive radial gaps allow process fluid to bypass the tube matrix along the shell wall, lowering overall heat recovery efficiency.
Yuhong Group provides standardized commercial execution terms for global engineering contractors, plant operators, and pressure vessel fabricators:
Minimum Order Quantity (MOQ): 1 Complete Stacked Exchanger Assembly or 1 Replacement Tube Bundle Core.
Incoterms & Shipping Ports: FOB Shanghai, FOB Qingdao, FOB Ningbo, or CIF / CFR destination ports worldwide.
Fabrication Lead Time: Standard stacked process units delivered within 45 to 60 calendar days following GA drawing approval; emergency shutdown turnaround bundle fabrication available in 25 days.
Third-Party Inspection (TPI): Fully compliant with BV, SGS, TÜV, Lloyd's Register, and ABS inspection protocols.
Petroleum Refining: Hydrotreater feed/effluent exchangers, Crude Distillation Unit (CDU) preheat trains, and amine treating reboilers.
Petrochemical Processing: Ethylene glycol plant condensers, naphtha splitters, and aromatics recovery exchangers.
Natural Gas & LNG: High-pressure gas compression coolers, glycol dehydration units, and FPSO top-side process modules.
Contact our engineering sales team to submit process data sheets or request commercial quotes for custom stacked shell and tube heat exchanger units, replacement u tube bundle assemblies, or forged heat exchanger tubesheet plates:
Company: Yuhong Group Co., Ltd.
Website: www.tema-heatexchanger.com
Direct Email: jimmy@steelseamlesspipe.com
Design Standards: ASME Section VIII Div 1, TEMA Class R/B/C, API 660, PED 2014/68/EU, ISO 9001
