ASTM A179 / ASME SA179 HEAT EXCHANGER TUBE – SEAMLESS COLD-DRAWN LOW-CARBON STEEL TUBE FOR SHELL AND TUBE HEAT EXCHANGER
ASTM A179 / ASME SA179 is a standard specification for seamless cold-drawn low-carbon steel tubes intended for tubular heat exchangers, condensers, and similar heat transfer apparatus. The specification covers tubes of minimum wall thickness, manufactured by the seamless process and cold drawn to achieve precise dimensional tolerances and consistent mechanical properties. These tubes are available in types including seamless, cold-drawn, and hot-drawn, and can be supplied in custom sizes, diameters, and thicknesses.
ASTM A179 / ASME SA179 seamless tubes are produced in various configurations to meet specific application requirements, including straight tubes, U-bend tubes, coil tubes, and fin tubes. The material is selected for its consistent quality, good ductility, and excellent thermal conductivity, making it ideal for pressure-containing components in heat transfer systems. Each tube is strictly subjected to various tests to ensure product quality.
U-Bend Tube Manufacturing ProcessU-bend tubes are manufactured after straight tubes are produced. The bending operation is performed in the cold state on an automatic U-bending machine. To ensure that wall thinning and diameter ovality are kept under control, a mandrel is inserted into the tubes during the bending process. The U-bend portion is subsequently stress relieved under controlled conditions and cycles to provide longer service life. Finished U-bent tubes undergo 100% hydrostatic leak testing and dye penetrant (DP) testing prior to dispatch.
Chemical Composition (per ASTM A179 / ASME SA179)The chemical composition requirements of ASTM A179 / ASME SA179 are as follows:
| Element | Composition (%) |
|---|---|
| Carbon (C) | 0.06 – 0.18 |
| Manganese (Mn) | 0.27 – 0.63 |
| Phosphorus (P) | 0.035 max |
| Sulfur (S) | 0.035 max |
The mechanical property requirements for ASTM A179 / ASME SA179 tubes are as follows:
| Property | Requirement |
|---|---|
| Tensile Strength, min | 325 MPa |
| Yield Strength, min | 180 MPa |
| Elongation in 50 mm, min | 35% |
| Hardness (HRB) | 72 max |
| Outside Diameter (mm) | Tolerance (± mm) |
|---|---|
| 3.2 ≤ OD < 25.4 | ±0.10 |
| 25.4 ≤ OD ≤ 38.1 | ±0.15 |
| 38.1 < OD < 50.8 | ±0.20 |
| 50.8 ≤ OD < 63.5 | ±0.25 |
| 63.5 ≤ OD < 76.2 | ±0.30 |
| OD ≥ 76.2 | ±0.38 |
| Outside Diameter (mm) | Tolerance (% over / under) |
|---|---|
| 3.2 ≤ OD < 38.1 | +20% / -0% |
| 38.1 ≤ OD ≤ 76.2 | +22% / -0% |
The ASTM A179 / ASME SA179 heat exchanger tube is available in a wide range of outside diameters:
12.7 mm, 15.88 mm, 16 mm, 18 mm, 19.05 mm, 20 mm, 22.24 mm, 25 mm, 25.4 mm, 31.75 mm, 35 mm, 38.1 mm, 44.45 mm, 50.8 mm, 57.15 mm, 63.5 mm, 76.2 mm
Wall thicknesses are available in BWG, SWG, and AWG gauges. Custom sizes can be produced upon customer request.
Related Standards and GradesASTM A179 / ASME SA179 is part of a family of specifications for heat exchanger and condenser tubes. Related grades and standards include:
ASTM A192 / ASME SA192 – Seamless carbon steel boiler tubes for high-pressure service
ASTM A210 / ASME SA210 – Seamless medium-carbon steel boiler and superheater tubes
ASTM A334 / ASME SA334 – Seamless and welded carbon and alloy steel tubes for low-temperature service
Each tube is subjected to non-destructive examination in accordance with ASTM A179 / ASME SA179 requirements:
Eddy Current Testing (ET) – For detection of surface and subsurface defects
Ultrasonic Testing (UT) – For detection of internal discontinuities
Hardness Testing (HT) – For verification of material condition
Magnetic Particle Testing (MT) – For surface defect detection in ferromagnetic materials
In addition to NDE, the following tests are performed to verify tube quality:
Hydrostatic Test – 100% of tubes are hydrostatically tested to verify leak-tight integrity
Flattening Test – To assess ductility and soundness of the tube
Flaring Test – To evaluate resistance to deformation
Flange Test – To check tube end ductility
ASTM A179 / ASME SA179 tubes are vulnerable to damage during transit and require careful handling. Tubes are packed in specially designed steel frames, which are fitted into wooden boxes or cases to ensure protection during transportation. Packaging options include woven bags and plywood cases.
ApplicationsASTM A179 / ASME SA179 seamless heat exchanger tubes are widely used across various industries and applications:
Pressure Vessels – Including cryogenic and high-pressure equipment
Heat Exchangers – Shell and tube heat exchangers, tubular heat exchangers
Condensers – Power plant and industrial condensers
Boilers – Fire-tube and water-tube boilers
Air Preheaters – Heat recovery systems
Finned Tubes – Enhanced heat transfer surface applications
Air Cooler Tubes – Air-cooled heat exchangers
Refineries and petrochemical plants
Power generation facilities
Steel plants and chemical factories
Fertilizer plants
Shipbuilding and offshore oil drilling
Pharmaceutical and specialty chemicals
Pulp and paper industry
Gas processing
Sea water equipment
Quantity (number of pieces or weight)
Outside diameter and wall thickness
Tube type (straight, U-bend, coil, or finned)
Length required (for straight tubes) or bend radius and leg length (for U-bend tubes)
Surface treatment requirement (if any)
Delivery period required
