ASTM A179 cold drawn seamless carbon steel pipe is mainly used in various sectors of the metal structure, facilities, mainly after the rust of steel pieces immersed in 440-460 ℃ melting zinc solution, so that the steel surface attached to the zinc layer, which play a preservative purpose.
Chemistry Composition:
| C, % | Mn, % | P, % | S, % |
| 0.06-0.18 | 0.27-0.63 | 0.035 max | 0.035 max |
Mechanical Properties:
| Tensile Strength, MPa | Yield Strength, MPa | Elongation, % | Hardness, HRB |
| 325 min | 180 min | 35 min | 72 max |
Outside Diameter & Tolerance
| 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 |
| 76.2 | ±0.38 |
Wall thickness & Tolerance
| Outside Diamter, mm | Tolerance, % |
| 3.2≤OD＜38.1 | +20/-0 |
| 38.1≤OD≤76.2 | +22/-0 |
Length: 5800mm; 6000mm; 6096mm; 7315mm; 11800mm; and so on.
Max length: 27000mm, also U bending can be offered.
U-Bend Fabrication Tolerances
| Item | Condition (when) | Tolercance |
|---|---|---|
| Nominal bend radius ≤ 2 x nominal OD | less than or equal to 12% | |
| Ovality | 2 x nominal OD < Nominal bend radius ≤ 4 x nominal OD | less than or equal to 10% |
| Nominal bend radius > 4 x nominal OD | less than or equal to 5% | |
| Nominal bend radius ≤ 2 x nominal OD | 0.75 x nominal wall | |
| Mimimum wall thickness | 2 x nominal OD < Nominal bend radius ≤ 4 x nominal OD | 0.8 x nominal wall |
| Nominal bend radius > 4 x nominal OD | 0.9 x nominal wall | |
| Nominal bend radius ≤ 8″ (200mm) | +/-3/64″(1mm) | |
| Bending Radius | 8″ (200mm) < Nominal bend radius ≤ 16″ (400mm) | +/-1/16″(1mm) |
| Nominal bend radius >16″ (400mm) | +/-5/64″(1mm) | |
| Disrance between legs | Max 1/16″(1.5mm) | |
| Wall thinning of bending area | Max 17% | |
| Difference between leg lengths at the ends | Leg length ≤ 16′ (4.88m) | +1/8″(3mm) |
| Leg length > 16′ (4.88m) | +3/16″(5mm) | |
| Deviation from plane of bend | ≤ 3/16″(1.5mm) | |
| Flattening on bend | ≤ 10% nominal diameter | |
| Straight leg length | ≤5m | +1/8″(3mm) |
| >5m | +3/16(5mm) | |
| Total tube length including radius | ≤6m | +3/16(5mm) |
| >6m | +5/16″(8mm) |
Wall thickness & Tolerance
| Outside Diamter, mm | Tolerance, % |
|---|---|
| 3.2≤OD＜38.1 | +20/-0 |
| 38.1≤OD≤76.2 | +22/-0 |
Main application of ASTM A179 cold drawn seamless tubes.
This is an effective way of metal corrosion, the use of the main features are the following:
- ASTM A179 cold drawn seamless pipe manufacturers with thick dense dense zinc layer covered in the cold drawn seamless tube surface, it can avoid cold drawn seamless tube matrix and any contact with the corrosion solution to protect the steel matrix from corrosion. In the general atmosphere, the surface of the zinc layer to form a layer of thin and dense zinc oxide surface, it is difficult to dissolve in water, so the steel matrix plays a protective role. If zinc oxide and other components of the atmosphere produce insoluble zinc salt, the anti-corrosion effect is more desirable.
- With iron – zinc alloy layer, combined with dense, and with the unique anti-corrosion in the marine atmosphere and atmospheric atmosphere.
- ASTM A179 cold drawn seamless pipe with a strong wear resistance due to the combination of solid, zinc – iron miscible.
- Since zinc has good ductility, its alloy layer and steel base attached to a solid, so hot-rolled parts can be cold, rolling, drawing, bending and other molding without damage to the coating.
- Hot-dip galvanized structural steel pipe, the equivalent of an annealing treatment, can effectively improve the mechanical properties of steel matrix to eliminate the steel forming welding stress, is conducive to the steel structure for turning.
- The surface of cold drawn seamless pipe after hot galvanized is bright and beautiful.
- Pure zinc layer is the most hot galvanized layer of galvanized layer, its nature is basically close to pure zinc, with ductility, so it is full of flexibility.
