DIN2391 ST45 ST52 Precision seamless steel tubes
Standard: EN10305-1, DIN2391
Steel grade: ST35, ST37-4, ST52, ST52-4, Q345B, SAE1010, SAE1020, SAE1026, SAE1045, CK45
Other carbon steel grades including alloyed steels and conditions are on request of clients
Delivery condition: BK, BKW, GBK, NBK
Application: automotive (shock absorbers, steering system, safety system, air springs), hydraulic tubing, hydraulic cylinders, high pressure fuel injection for diesel.
Chemical composition:
| Material No. | C, max | Si, max | Mn | P, max | S, max | |
| ST45 | 1.0408 | 0.21 | 0.35 | 0.40, min | 0.025 | 0.025 |
| ST52 | 1.0580 | 0.22 | 0.55 | 1.60, max | 0.025 | 0.025 |
Dimensional range:
OD: Up to 90mm
WT: Up to 5mm
Length: Cut-to-length service is available, minimum to 30mm
Any specific size is to be discussed before offer
The tube be 100% eddy current tested
Ultrasonic test is as option
ID accuracy: H8, H9
Straightness ≤1mm/1000mm
Roughness: Ra ≤0.6
Delivery condition for availability:
| BK | Cold drawn / hard |
| BKW | Cold drawn / soft |
| GBK | Bright annealed |
| NBK | Bright normalized |
The internal and external surface finish of the tubes shall be typical of the manufacturing process and, where applicable, the heat treatment, and it shall be such that any surface imperfections such as ridges, dents or shallow grooves requiring dressing can be identified.
Any surface imperfections, whose depth cannot be clearly identified, or,
- It shall be permissible to dress, only by grinding or machining, surface imperfections provided that, after doing so, the dimensions are within the specified tolerances. All dressed areas shall blend smoothly into the contour of the tube.
- Surface imperfections which encroach on the specified minimum wall thickness shall be considered defects.
The tubes shall have smooth outer and inner surface. The roughness Ra shall be:
≤4 μm on the outer and inner surface of tubes in the delivery conditions +C and +LC.
≤4 μm on the outer surface of tubes in the delivery conditions +SR, +A and +N.
The tubes are tested by means of following norms
EN10002-1
EN10233
EN10234
EN10246-1
EN10246-3
EN10246-7
Tubes shall be delivered with square cut ends. The ends are free of excessive burrs.
The tubes are bundled in the waterproof plastic sheet and packed in the wooden cases
The case is most suitable for hanging by forklift.
EN10204-3.1 MTC shall be issued
EN10204-3.2 MTC is as option
