Material | C | Si | Mn | P | S | Cr | MO | NI | Al | Cu | Ti | V |
P235GH | ≤0.16 | ≤0.35 | ≤1.20 | ≤0.025 | ≤0.025 | ≤0.3 | ≤0.08 | ≤0.3 | ≤0.02 | ≤0.3 | ≤0.04 | ≤0.02 |
20G | 0.17-0.24 | 0.17-0.37 | 0.35-0.65 | ≤0.03 | ≤0.03 | - | - | - | - | - | - | - |
Material | Tensile Strength | Yield | Extension |
20G | 410-550 | ≥245 | ≥24 |
P235GH | 320-440 | 215-235 | 27 |
360-500 | 25 |
Material | Test | ||||||
20G: | Flattening | Hydraulic | Impact Test | NDT | Eddy | Grazin size | Microscopic structure |
P235GH | Flattening | Hydraulic | Impact Test | NDT | Electromagnetic | Drift expanding | Leak tightness |
If there is no special requirements, pipe gonna be delivery as norminal outter diameter and norminal wall thickness. As follow sheet
Classification designation |
Method of manufacture |
Size of pipe |
Tolerance |
|||
Normal grade |
High grade |
|||||
W H |
Hot Rolled(extrude) pipe |
Norminal outter Diameter (D) |
<57 |
士 0.40 |
±0,30 |
|
57 〜325 |
SW35 |
±0.75%D |
±0.5%D |
|||
S>35 |
±1%D |
±0.75%D |
||||
>325 〜6。。 |
+ 1%D or + 5.Take lesser one一2 |
|||||
>600 |
+ 1%D or + 7,Take lesser one一2 |
|||||
Norminal Wall Thickness (S) |
<4.0 |
±|・丨) |
±0.35 |
|||
>4.0-20 |
+ 12.5%S |
±10%S |
||||
>20 |
DV219 |
±10%S |
±7.5%S |
|||
心219 |
+ 12.5%S -10%S |
土 10%S |
W-H |
Thermal expansion pipe |
Norminal outter Diameter
(D) |
all |
±1%D |
±0.75%。 |
Norminal Wall Thickness
(S) |
all |
+ 20%S -10%S |
+ 15%S -io%s |
||
W-C |
Cold drawn(rolled) Ppipe |
Norminal outter Diameter
(D) |
<25.4 |
±'L1j |
— |
>25.4 〜4() |
±0.20 |
||||
>40 〜50 |
|:0.25 |
— |
|||
>50 〜60 |
±0.30 |
||||
>60 |
±0.5%D |
||||
Norminal Wall Thickness (S) |
<3.0 |
±0.3 |
±0.2 |
||
>3.0 |
S |
±7.5%S |
According to the requirements of the purchaser and stated in the contract, the steel pipe with outer diameter ≤76mm and wall thickness ≤8mm can be done flaring test . The experiment was performed at room temperature with a taper of 60 °. After the flaring, the flaring rate of the outer diameter should meet the requirements of the following table, and the test material must not show cracks or rips
Steel Type |
Outter diameter flaring rate of steel pipe/% |
||
Inner Diameter/Outter Diameter |
|||
<0.6 |
>0.6 〜0.8 |
>0.8 |
|
High-quality carbon structural steel |
10 |
12 |
17 |
Structural alloy steel |
8 |
10 |
15 |
•The inner diameter is calculated for the sample. |