F91 (X10CrMoVNb9-1), IS AN ALLOY STEEL WITH CHROME AND AN ADDITION OF NB, WHICH HAS ELEVATED MECHANICAL CHARACTERISTICS AND IT IS VERY OFTEN USED IN THE CHEMICAL AND PETROCHEMICAL INDUSTRIES FOR THE FABRICATION OF FLANGES, VALVES, TUBES AND FOR EQUIPMENTS THAT REQUIRE AN EXCELLENT CREEP RESISTANCE AND TO EMBRITTLEMENT BECAUSE OF HYDROGEN UNDER PRESSURE AND AT AN ELEVATED TEMPERATURE (UP TO 600°C).
CORRESPONDENCE TO INTERNATIONAL DESIGNATIONS
| QUALITY | EUROPE | GERMANY | FRANCE | SPAIN | G.B. | USA | |
|---|---|---|---|---|---|---|---|
| EN | DIN | W.n. | AFNOR | UNE | B.S. | ASTM | |
| F91 | X10CrMoVNb9-1 | X10CrMoVNb9-1 | 1,4903 | - | - | - |
ASTM A182 F91 ASME SA 182 |
CHEMICAL ANALYSIS
| C | Mn | Si |
P max |
S max |
Cr |
Ni max |
Mo |
Zr max |
Al | N | Nb | V |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0,08 ÷ 0,12 | 0,30 ÷ 0,60 | 0,20 ÷ 0,50 | 0,020 | 0,010 | 8,00 ÷ 9,50 | 0,40 | 0,85 ÷ 1,05 | 0,01 | 0,020 | 0,03 ÷ 0,07 | 0,06 ÷ 0,10 | 0,10 ÷ 0,25 |
CONCENTRATION LIMITS OF THE ELEMENTS THAT ARE NOT INDICATED IN THE TABLE CAN BE DEDUCED IN THE EN 10020 REGULATION.
MECHANICAL CHARACTERISTICS
| STEEL | NORMALISATION TEMPERATURE 900°C MIN – TEMPERING TEMPERATURE 620°C MIN | |||||
| SYMBOLIC | Re min | Rm min | A min | Z min | Durezza HB | |
| N/mm2 | % | % | max | |||
| F91 | 415 | 620 | 20 | 40 | 190÷248 | |
USUALLY AVAILABLE EX STOCK
| M.T. COLORATION | QUALITY | HEAT TREATMENT | SURFACE | DIAMETER (mm) |
|---|---|---|---|---|
 |
F91 | Normalised and stress relieved | rolled peeled / forged turned | 30-400 |
 |
F91 | Annealed | rolled | 30-220 |
 |
Download technical sheet |