ST37 ST35 ST52 high precision steel tube pipe
Din 2391 Seamless steel pipe (Din 2391, En 10305-1, en 10305-4, BS 6323 precision seamless steel tube NBK GBK)
Specification
| Standard | DIN2391 DIN1630 DIN2448 |
| Grade | ST35/E235 ST37.4 ST45/E255 ST52/E355 |
| Delivery Condition | NBK(+N) BK(+C) GBK(+A) BKW(+LC) BKS(+SR) |
| Size | OD:4 to 219mm Thickness 0.5-35mm, Length: 3m,5.8,6 or according to requirements |
| Finish | Galvanized surface (Sliver/Yellow/Colorful) Zinc coating of 8-12um |
| Application | Hydraulic System; Car/bus; construction vehicle |
| Delivery time | A.3 days if this good is stock goods.
B. About 30 days according to the quantity |
SURFACE TREATMENTS
1. Bare Tube (No coating): Bright and smooth
A. Silver galvanized
B. Yellow galvanized
C. Olive green coated
Layer thickness: 8-20um, Salty Spray Test: 48-150 hours
3. Black phosphate
Different Fields
1. Automotive fields
A. Fuel injection lines/nozzles
B. CNG (Compressed Nature Gas) tube-- Burst pressure: 1307Bar, Working Pressure: around 350bar
C. Drive transmission: Steering column elements
D. Gear shafts, hand brake, front axles, airbag inhalators, stabilizers, seat fasteners, front-wheel drive shafts
2. Hydraulic Fields
A. Hydraulic circuits (HPL), pneumatic lines, and hydraulic suspension
B. Hydraulic cylinders (HPZ)
Chemical Composition
|
Steel Grade |
C |
Si |
Mn |
P |
S |
Al |
|
|
Name |
No. |
max |
max |
max |
max |
max |
max |
|
ST35 |
1.0308 |
0.17 |
0.35 |
0.4（min） |
0.025 |
0.025 |
— |
|
ST45 |
1.0408 |
0.21 |
0.35 |
0.4（min） |
0.025 |
0.025 |
— |
|
ST52 |
1.058 |
0.22 |
0.55 |
1.6 |
0.025 |
0.025 |
— |
Mechanical Properties
|
Steel Grade |
Yield Strength (Mpa) | Tensile Strength (Mpa) | Elongation（%） | |
|
Name |
No. |
ReH (min) | Rm(min) |
A(min) |
|
ST35 |
1.0308 |
235 |
340 to 480 |
25 |
|
ST45 |
1.0408 |
255 |
440 to 570 |
21 |
|
ST52 |
1.058 |
355 |
490 to 630 |
22 |
Tolerance
|
OD |
Allowable tolerance |
Special Tolerance |
||
|
|
GB/T3639 |
DIN2391 |
OD |
WT |
|
4mm-20mm |
±0.10mm |
±0.08mm |
±0.05mm |
±0.05mm |
|
20mm-30mm |
±0.10mm |
±0.08mm |
±0.08mm |
±0.08mm |
|
31mm-40mm |
±0.15mm |
±0.15mm |
±0.10mm |
±0.08mm |
|
41mm-60mm |
±0.20mm |
±0.20mm |
±0.15mm |
±0.15mm |
|
61mm-80mm |
±0.30mm |
±0.30mm |
±0.20mm |
±0.20mm |
|
81mm-120mm |
±0.45mm |
±0.45mm |
±0.30mm |
±0.30mm |
Delivery Condition
|
Designation |
Symbol |
Description |
| Cold finished (hard) | BK(+C) | Tubes do not undergo heat treatment following the final cold forming and, thus, have a rather high resistance to deformation |
| Cold finished (Soft) | BKW | The final heat treatment is followed by cold drawing involving limited deformation. Appropriate further processing allows a certain degree of cold forming (e.g. bending, expanding) |
| (+LC) | ||
| Cold finished and stress-relieved | BKS(+SR) | Heat treatment is applied following the last cold forming process. Subject to appropriate processing conditions, the increase in the residual stresses involved enables both forming and machining to a certain degree. |
| Annealed | GBK(+A) | The last Cold forming process is followed by annealing in a controlled atmosphere. |
| Normalized | NBK(+N) | The last cold forming process is followed by annealing above the upper transformation point in a controlled atmosphere. |
Quality Assurance
1. Strict according to DIN2391/EN10305 or other standard.
2. Sample: Sample is free for test.
3. Tests: Salt spray test/Tensile test / Eddy current / Chemical composition test according to customers' request
4.Certificate: IATF16949, ISO9001, SGS etc.
5.EN 10204 3.1 Certification
Product packaging
