Seamless cold drawn precision steel tubes
Area of use
The applications for seamless and welded precision steel tubes are determined by special technical features. These are as follows:
• High dimensional accuracy for inside and outside diameters
• Smooth surfaces achieved by drawing
• Improved strength characteristics due to cold forming
• Closely graduated dimensional range
• Low concentricity in welded precision steel tubes
Production method
The pre-material for precision steel tubes is selected, fully killed LD or electrical steel cast continuously in slabs. It is first checked and then processed into hollow pre-material tubes.
The hollows are cold formed on state of the art drawing benches. Subsequent heat treatment and passage through high-tech straightening and testing benches complete the production process into cold drawn precision steel tubes.
Size range
OD: 4 - 30mm (+/-0.08mm)
OD: 32 - 40mm (+/-0.15mm)
OD: 42 - 50mm (+/-0.20mm)
WT: 0.5 - 1mm (+/-10%)
Delivery conditions, following finishes for EN10305-1
| Designation | Abbreviation | Explanation |
| Cold drawn/hard | +C | No heat treatment after the final cold drawing process. |
| Cold drawn/soft | +LC | After the final heat treatment there is a suitable drawing pass. |
| Cold drawn and stress relieved | +SR | After the final cold drawing process there is a stress relief heat treatment in a controlled atmosphere. |
| Annealed | +A | After the final cold drawing process the tubes are annealed in a controlled atmosphere. |
| Normalized | +N | After the final cold drawing operation the tubes are normalised in a controlled atmosphere. |
Steel grades
| Name | Material number |
| E235 | 1.0308 |
| E355 | 1.0580 |
Other steel qualities on request
For example: C15, C35E, P460N, 16MnCr5, 20MnCr5, 20MnV6, 25CrMo4, 42CrMo4, 33MnB5, 16Mo5, ASTM A213 T11
Scope of testing
A 100% non-destructive eddy current test in acc. with ISO 10893-1 is carried out at additional cost. A checking of the mechanical properties also takes place.
The following tests may be carried out in addition to the standard EN tests:
• Ultrasonic test in acc. with ISO 10893-10, U2
• Factory acceptance test
• Customer/third party acceptance
• Dimensional check using laser
• Impact test
• Material identification test
