ASTM A179/A179M, from Hebei K-Steel Pipe Industry is a standard specification for seamless cold-drawn low-carbon steel tubes primarily used in tubular heat exchangers, condensers, and similar heat transfer equipment. It is widely valued for its high dimensional accuracy, smooth surface finish, and excellent thermal conductivity
Key Specifications and Grades
The standard covers tubes with an outside diameter (OD) ranging from 1/8 inch to 3 inches (3.2 mm to 76.2 mm). It typically includes two primary grades
Grade A: A standard grade with a minimum yield strength of 35 ksi (240 MPa), ideal for general industrial applications.
Grade C: A higher-strength version with a minimum yield strength of 47 ksi (325 MPa), suitable for more demanding high-pressure environments.
Chemical and Mechanical Properties
Property Requirement
Carbon Content 0.06% – 0.18% (ensures ductility and weldability)
Manganese 0.27% – 0.63%
Tensile Strength Min. 47 ksi (325 MPa)
Hardness Max. 72 HRB (Rockwell Hardness, B scale)
Thermal Treatment Must be heat treated (annealed) at 1200°F (650°C) or higher after final cold drawing
Manufacturing and Testing
As specified by ASTM International, these tubes must be manufactured using the seamless process and finished through cold drawing. To ensure safety under high pressure, each tube must undergo rigorous quality checks:
Flattening and Flaring Tests: To verify the material's ductility and ability to withstand mechanical deformation.
Hydrostatic or NDT Test: Every tube is subjected to a water pressure test or a non-destructive electric test to ensure it is leak-free.
Dimensional Checks: Precise wall thickness and outer diameter tolerances are strictly maintained.
Due to their reliability in varying temperatures and pressures, ASTM A179 tubes are essential in several sectors:
Power Plants: In condensers and boiler feed-water heaters.
Petrochemical Industry: For refining and cooling processes in heat exchangers.
Marine Systems: Used in seawater cooling equipment due to its adaptability.
Sugar Mills & Distilleries: For various thermal processing needs.
