Yuhong Group Co., Ltd. supplies shell and tube heat exchangers, pressure vessels, air coolers, and a full range of compatible components including tube bundles, U-tubes, bare and finned heat exchanger tubes, tubesheets, baffles, and heads. The product described below is a replacement-grade tube bundle built around ASME SA179 seamless cold-drawn tubes for shell and tube heat exchanger service.
This tube bundle is a removable heat transfer core for shell and tube exchangers operating in non-corrosive or mildly corrosive services. It uses ASME SA179 / ASTM A179 seamless cold-drawn low-carbon steel tubes, mechanically expanded into a forged carbon steel tubesheet. Baffles, tie rods, and spacers are supplied in compatible carbon steel grades to maintain tube support and flow distribution across the bundle.
The bundle is configured as a direct replacement: dimensions, tube count, layout pattern, and connection details are matched to the original equipment drawings or measured samples, minimizing downtime during maintenance turnarounds.
| Parameter | Value |
|---|---|
| Tube standard | ASME SA179 / ASTM A179 |
| Tube type | Seamless, cold-drawn |
| Outside diameter range | 3.2 mm – 76.2 mm (1/8 in – 3 in) |
| Tube configuration | Straight or U-bend |
| Tensile strength, min | 325 MPa (47 ksi) |
| Yield strength, min | 180 MPa (26 ksi) |
| Elongation, min | 35% |
| Hardness, max | 72 HRB |
| Tubesheet material | Forged carbon steel (ASME SA266 Gr.2N or ASME SA105, per service) |
| Certification | ASME U Stamp, PED, with MTR to EN 10204 3.1 |
The cross-reference below uses a horizontal two-row format: standards on the top row and approximate grade designations on the bottom row. It is intended for preliminary sourcing and document review only. The governing specification remains ASME SA179 / ASTM A179.
| ASTM/ASME | GB/T 5310 | GOST 8734 | EN 10216-2 |
|---|---|---|---|
| A179/SA179 | Steel 10 | Steel 10 | P235GH |
These are approximate cross-references. Confirm chemistry, minimum wall, hardness, and tensile properties against ASME SA179 / ASTM A179 before order placement.
A179 is deliberately low-carbon: C 0.06–0.18%, Mn 0.27–0.63%, with P and S capped at 0.035% each. The low carbon and residual control serve two purposes. First, the tube can be cold-flared and expanded into a tubesheet without cracking, which is essential for reliable tube-to-tubesheet joints. Second, the clean, smooth surface produced by cold drawing reduces deposit accumulation on the tube ID, which helps sustain heat transfer efficiency over operating cycles.
Corrosion resistance is moderate by design. A179 is suitable for water, steam, oil, and gas streams with low chloride content and controlled oxygen levels. In closed-loop cooling water systems where dissolved oxygen is maintained below typical thresholds, tube life is predictable. For services with high chlorides, wet CO₂, or aggressive process fluids, alternative materials should be evaluated.
Tubes are produced by the seamless process and cold-drawn through dies, followed by heat treatment at 650°C or higher. The cold-drawing route gives tighter dimensional tolerances and a smoother surface than hot-rolled tubing, which matters for both heat transfer and tube-to-tubesheet fit.
Inspection includes chemical composition verification, tensile and yield testing, hardness testing (72 HRB max), flattening and flaring tests, and hydrostatic testing per tube. Eddy current testing is available as a non-destructive supplement. The bundle assembly is dimensionally checked against the replacement drawing, and tube-to-tubesheet joints are expansion-tested before dispatch.
Oil refining: crude preheat trains, tower overhead condensers, lube oil coolers
Power generation: feedwater heaters, generator air coolers, turbine oil coolers
Chemical and petrochemical: process fluid heating/cooling, solvent recovery condensers
HVAC and district heating: chillers, heat pumps, heating network exchangers
What is the difference between minimum wall and average wall for A179 tubes? ASTM A179 specifies minimum wall thickness. When a drawing or specification calls for “average wall," the tube is ordered to a nominal wall with tolerances applied differently. Mixing the two ordering methods in the same bundle can cause tube expansion problems. Confirm the wall basis before issuing a purchase order.
When should A179 be replaced by a higher-grade tube? If the tube-side fluid contains chlorides above trace levels, operates at temperatures approaching 400°C, or carries suspended solids at high velocity, the low-carbon chemistry of A179 may not provide adequate service life. In those cases, alloy or stainless tube materials are more appropriate.
Can the bundle be supplied as a drop-in replacement? Yes. Send the equipment model, nameplate data, or original bundle drawings. Tube layout, pitch, length, baffle spacing, and tubesheet dimensions are matched to the existing shell to avoid field modification.
