ASME SA179 Seamless Cold-Drawn Low-Carbon Steel U-Bend Tubes for
Tubular Heat Exchangers and Condensers
1. ASME A179/ ASTM A179 cold drawn U-bend Tube 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.
2. With iron - zinc alloy layer, combined with dense, and with the
unique anti-corrosion in the marine atmosphere and atmospheric
atmosphere.
3. ASTM A179 cold drawn seamless pipe with a strong wear resistance
due to the combination of solid, zinc - iron miscible.
4. 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.
5. 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.
6. The surface of cold drawn seamless pipe after hot galvanized is
bright and beautiful.
7. 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.
1
Factory test and other terms:
1.Hydrostatic or Nondestructive Electric Test
2.Heat Treatment: according to Standard
3.Surface Condition:According to Standard.
4.Grain Size:According to standard
5.Sampling:flattening,flaring,grain size,Marking
6.we provide bevel end,plastic cap, varnish coating, oiled or black
painted to prevent rustand other packing service.
Technical Requirements:
Straight Tubes Standard Specification For Bending:
ASME SA 213; ASTM A179 ;ASTM A210 etc
Marking: Before Bending By Marking Machine All Over The Tube Length (Bent
Section After Heat Treatment Without Marking)
Note: Marking is also possible After Bending On The Straight Parts Of
U-Bending Tube.
U-Bend Tubes:
-TEMA RCB 2.31 Standard Of The Tubular Exchanger Manufacturers
Association (9th Edition).
-ASTM A688/ASME SA688 Standard Specification For Welded Tubes Of
Austenitic Corrosion Resistant
Steel Grade Designed For Feed Water Boilers.
-ASTM B163/ASME SA163 Standard Techinical Requirements For Tubes Of
Nickel And Nickel Alloy For
Condensers And Heat Exchangers.
The Chemical Composition:
| Chemical Composition | C | Mn | P ≤ | S ≤ | Si ≤ |
| 0.06--0.18 | 0.27--0.63 | 0.035 | 0.035 | 0.25 |
| OD Inch(mm) | + | -- | WT Inch(mm) | + | -- |
| ＜1(25.4) | 0.10 | 0.10 | ≤1. 1/2 (38.1) | 20% | 0 |
1 to 1.1/2 (25.4 to 38.1) | 0.15 | 0.15 | ＞1. 1/2 | 22% | 0 |
1.1/2 to 2 (38.1 to 50.8) | 0.20 | 0.20 | | | |
2 to 2. 1/2 (50.8 to 63.5) | 0.25 | 0.25 | | | |
2. 1/2 to 3 (63.5 to 76.2) | 0.30 | 0.30 | | | |
