Yuhong Group supplies bimetallic finned tube bundles built on ASME SA179 seamless cold-drawn low-carbon steel base tubes with Aluminum 1060 fins. The bundle is the heat-transfer core of an air cooler: process fluid passes through the SA179 tube side, while ambient air is forced across the extended aluminum fin surface. The material pairing is selected to solve a specific engineering problem — achieving a low fin-root contact resistance without introducing a metallurgical joint that would complicate inspection or repair in the field.
Table 1 — Material and mechanical data
| Item | Specification |
|---|---|
| Base tube | SA179 seamless cold-drawn low-carbon steel |
| Fin material | Aluminum 1060 |
| Yield strength, base tube | ≥180 MPa |
| Tensile strength, base tube | ≥325 MPa |
| Elongation, base tube | ≥35% |
| Thermal conductivity, Aluminum 1060 | ~234 W/(m·K), typical |
Table 2 — Fin bond and operating envelope
| Parameter | Value / basis |
|---|---|
| Fin-tube bond | Mechanically formed aluminum outer layer; integral fin-tube bond |
| Contact resistance, new extruded bimetallic tube | 0.00010–0.00020 m²·K/W |
| Normal tube-wall temperature limit | Up to ~200 °C, conservative baseline |
| Extended reference ceiling | Toward 280 °C, subject to base-tube/fin combination and cyclic review |
| Procurement note | State fin bond type explicitly; dimensional compliance alone does not define thermal performance |
Cyclic service: review startup excursions against the full temperature cycle, not only steady-state duty.
Temperature class: this construction differs from lower-temperature wound-fin options.
Typical service: refinery and petrochemical air coolers; reactor effluent cooling; compressed gas cooling; power-generation auxiliary cooling where water cooling is unavailable.
Construction basis: pressure-boundary components fabricated and tested under the ASME Section VIII framework; SA179 applied as the tube product specification.
Documentation: SA179 base-tube and Aluminum 1060 fin-strip material certificates issued with the inspection package.
Traceability: all test records traceable to the bundle serial number.
Tube level (per SA179)
Chemical composition analysis of base tube.
Tensile, yield, and elongation verification.
Hydrostatic test or nondestructive electric test (eddy current) on each tube, as permitted by SA179.
Dimensional check: OD, wall thickness, length, straightness.
Visual inspection of tube surface and ends.
Fin and bond level
Fin strip chemical composition and mechanical property check (Aluminum 1060).
Fin geometry inspection: fin height, fin density/pitch, fin thickness.
Fin bond integrity and contact-resistance check on production samples.
Visual inspection of finned surface for forming defects.
Fabrication level
Tube-to-tubesheet joint inspection after expansion, plus seal-weld inspection where specified.
Weld nondestructive testing where specified: RT, UT, PT, and MT.
PMI (positive material identification) on base tube and weld areas where specified.
Hardness check on weld and heat-affected zones where specified.
Bundle level
Hydrostatic test of the assembled bundle: tube-to-tubesheet joints, tube tightness, header soundness.
Pneumatic / air leak test where specified.
Final dimensional inspection: tube count, tube length, bundle envelope, header connection orientation.
Final visual inspection and surface protection check before packing.
Third-party inspection (TPI): scope, witness points, and document review confirmed at purchase order stage.
Packing: iron-frame + plywood case; pallet or woven-bag for component-only orders.
Export packing: configured for ocean freight and long overland leg combinations.
Trade terms: EXW, FCA, FOB, CFR, and CIF are all acceptable; quoted per order and port.
MOQ: 1 piece.
Lead Time: typically 20–80 days, depending on bundle size, tube count, header fabrication, and tubesheet drilling scope.
Spare supply: finned tubes, tubesheets, and headers to drawing without a complete bundle order.
Material certificates: SA179 base tubes and Aluminum 1060 fin strip.
Test records: tube-level test reports, fin bond check records, NDT reports where applicable, hydrostatic/pneumatic test report, and final dimensional inspection report, all tied to bundle serial number.
Inspection package: issued with shipment.
Certification scope: confirmed at purchase order stage to match project documentation requirements.
Q: Can fin density be adjusted for thermal duty?
A: Yes. Fin density and fin height are configured against thermal duty, airflow, and allowable air-side pressure drop. SA179 / Aluminum 1060 remains unchanged unless temperature or corrosion review requires otherwise.
Q: What are MOQ and Lead Time?
A: MOQ is 1 piece; Lead Time is typically 20–80 days depending on bundle size and fabrication scope.
Q: Which trade terms do you accept?
A: EXW, FCA, FOB, CFR, and CIF are all acceptable and quoted per order and port.
Q: Can replacement bundles be supplied without fan and frame?
A: Yes. Replacement bundles, headers, and tubesheets can be manufactured to existing drawings.
Send tube count, tube length, fin density, design tube-wall temperature, and header connection details.
State required NDT methods and TPI witness points so they are priced into the quotation.
Include startup excursion conditions if applicable.
Email: vladimir@steelseamlesspipe.com.
Response: material-confirmation note and quotation covering trade terms, Lead Time, and documentation scope.
