BS EN 10216-2 Seamless steel tubes for pressure purposes – Technical delivery conditions – part 2: Non- alloy and alloy steel tubes with specified elevated temperature
This Part of EN10216 specifies the technical delivery conditions in two categories for seamless tubes of circular cross section, with specified elevated temperature properties, made of non-alloy and alloy steel.
Steel Grade: 20MnNb6 Steel Number: 1.0471
| Chemical composition (cast analysis)a, in % by mass |
| Elements | 20MnNb6 |
| C | ≤0.22 |
| Si | 0.15-0.35 |
| Mn | 1.00-1.50 |
| P max | 0.025 |
| S max | 0.020 |
| Al total | ≤0.060 |
| Cu | ≤0.30 b |
| Nb | 0.015-0.10 |
a Elements not included in this Table shall not be intentionally added to the steel without the agreement of the purchaser, except for elements which may be added for finishing the cast. All appropriate measures shall be taken to prevent the addition of undesirable lelments from scrap or other materials used in the steel making process.
b Option 2: In order to facilitate subsequent forming operations, an agreed maximum copper content lower than indicated and an agreed specified maximum tin content shall apply.
Mechanical properties
| Steel grade | Tensile properties at room temperature | Impact properties a | ||||||||||
| Upper yield stength or proof strength ReH or RP0.2 for Wall Thickness T min. | Tensile Strength Rm | Elongation A min. % a | Minimum average absorbed energy KV J at a temperature of ℃ | |||||||||
| T ≤16 | 16＜T≤40 | 40＜T≤60 | 60＜T≤100 | l | t | l | t | |||||
| Mpa | Mpa | Mpa | Mpa | Mpa | 20 | 0 | -10 | 20 | 0 | |||
| 20MnNb6 | 355 | 345 | 335 | – | 500 to 650 | 22 | 20 | – | 40 | – | 27 | |
a l = longitudinal t = transverse