PN-EN 10305-3 Calibrated steel tubes for precision applications
The advantage of steel tubes for precision applications is the high precision of their manufacturing, the good quality of their surface, and the guaranteed mechanical and technological properties. That is why the pipes are widely used in the machining industry and in the automotive industry.
PN-EN10305-3
Delivery condition
| Designation | Symbol | Description |
| Welding and cold calibration | +CR1 | Usually not thermally processed but appropriate for final annealing |
| +CR2 | Not intended for thermal processing after the welding and calibration processes are completed | |
| Annealed | +A | After the welding and calibration processes are completed, the pipes are annealed in a controlled atmosphere |
| Normalized | +N | After the welding and calibration processes are completed, the pipes are normalized in a controlled atmosphere. This delivery condition can be achieved through direct processing. |
Chemical composition (ladle analysis)
| Steel grade |
% of the mass |
|||||
| Steel symbol |
Steel number | C max | Si max | Mn max | P max | S max |
| E155 | 0,11 | 0,35 | 0,70 | 0,025 | 0,025 | |
| E190 | 0,10 | |||||
| E195 | 0,15 | 0,35 | 0,70 | 0,025 | 0,025 | |
| E22 | 0,14 | |||||
| E235 | 0,17 | 0,35 | 1,20 | 0,025 | 0,025 | |
| E260 | 0,16 | |||||
| E275 | 0,21 | 0,35 | 1,40 | 0,025 | 0,025 | |
| E320 | 0,20 | |||||
| E355 | 0,22 | 0,55 | 1,60 | 0,025 | 0,025 | |
| E370 | 0,21 | |||||
| E420 | 0,16 | 0,50 | 1,70 | 0,025 | 0,025 | |
Mechanical properties in room temperature for the +CR!, +A and +N delivery conditions
| Steel grade |
Minimum values for the delivery condition | ||||||
| +CR1 | +A | +N | |||||
| Steel symbol | R m MPa | A % | Rm MPa | A % | Rm MPa | ReH Mpa | A % |
| E155 | 290 | 15 | 260 | 28 | 270 do 410 | 155 | 28 |
| E195 | 330 | 8 | 290 | 28 | 300 do 440 | 195 | 28 |
| E235 | 390 | 7 | 315 | 25 | 340 do 480 | 235 | 25 |
| E275 | 440 | 6 | 390 | 21 | 410 do 550 | 275 | 21 |
| E355 | 540 | 5 | 450 | 22 | 490 do 630 | 355 | 22 |
Mechanical properties (minimum values) in room temperature for the +CR2 delivery condition
| Steel grade | Tensile strength Rm MPa | Yield limit ReH Mpa | Elongation at break A % |
| Steel symbol | |||
| E190 | 270 | 190 | 26 |
| E220 | 310 | 220 | 23 |
| E260 | 340 | 260 | 21 |
| E320 | 410 | 320 | 19 |
| E370 | 450 | 370 | 15 |
| E420 | 490 | 420 | 12 |
Inspection and test list
| Inspection or test type | Test frequency | ||
| Internal tests | Acceptance tests | ||
| Mandatory |
Chemical analysis | M | M |
| Tensile testing | M | One per tested batch | |
| Dimension verification | M | M | |
| Visual inspection | M | M | |
| Optional | Flattening test or expansion test (option 20) | M | One per tested batch |
| Roughness testing | Not applicable | One per tested batch | |
| NDT of the weld in order to identify any longitudinal discontinuities | Not applicable | Every individual pipe | |
| NDT of the whole pipe circumference in order to identify any longitudinal discontinuities | |||
| NDT in order to detect any leaks | |||
| Transverse NDT of the weld in order to identify any discontinuities | |||
