Luke Steel is a reliable supplier of Alloy Steel F91 Flanges, manufactured in Houston, USA. These flanges create strong, lasting connections in high-temperature and high-pressure applications. Made from a chromium-molybdenum alloy, F91 flanges withstand extreme thermal stress, pressure, and oxidation. They are commonly used in industries like power generation, petrochemicals, and oil and gas, where strength and resistance to corrosion are crucial. Luke Steel is committed to quality, delivering F91 flanges that meet industry standards for safe, effective, and long-lasting performance in the toughest environments worldwide.
Alloy Steel F91 Flanges contain about 9% chromium, 1% molybdenum, and small traces of vanadium, providing high strength, oxidation resistance, and durability at high temperatures. These flanges have a tensile strength of 690 to 850 MPa, yield strength of around 485 MPa, and an elongation of 18 to 22%. Designed for use in environments up to 650°C, F91 flanges maintain mechanical integrity under thermal cycling and high-pressure conditions. Their composition offers high creep resistance, making them suitable for use in superheaters, steam lines, and critical pressure systems.
Alloy Steel Flanges Specification : ASTM A182 / ASME SA182
Dimension Standard : ANSI/ASME B16.5, B 16.47 Series A & B, B16.48, BS4504, BS 10, EN-1092, DIN, etc.
Standard : ANSI Flanges, ASME Flanges, BS Flanges, DIN Flanges, EN Flanges, etc.
Size : 1/2″ (15 NB) to 48″ (1200NB)
Class / Pressure : 150#, 300#, 600#, 900#, 1500#, 2500#, PN6, PN10, PN16, PN25, PN40, PN64 etc.
Flange Face Type : Flate Face (FF), Raised Face (RF), Ring Type Joint (RTJ)
DIN Flanges : DIN 2527, 2566, 2573, 2576, 2641,2642, 2655, 2656, 2627, 2628, 2629, 2631, 2632, 2633, 2634, 2635, 2636, 2637,2638, 2673.
JIS Flanges : JIS B2220 5K, JIS B2220 10K, JIS B2220 16K, JIS B2220 20K
BS Flanges : BS4504 PN 6, BS 4504 PN 10, BS4504 PN 16, BS4504 PN 25, BS4504 PN 40, BS 4504 PN 64, BS 4504 PN 100, BS 4504 PN 160, BS 4504 PN 250, BS 10, BS Table D, BS Table E, BS Table F, BS Table H.
| Grade | C | Mn | P | S | Si | Ni | Ch | Mo | Cb | N |
|---|---|---|---|---|---|---|---|---|---|---|
| F91 | 0.08-0.12 | 0.30-0.60 | 0.020 | 0.010 | 0.20-0.50 | 0.40 | 8.0-9.5 | 0.85-1.05 | 0.06-0.10 | 0.03-0.07 |
| Grade | Tensile Strength (MPa) min | Yield Strength 0.2% Proof (MPa) min | Elongation (% in 50mm) min | Hardness | |
|---|---|---|---|---|---|
| Rockwell B (HR B) max | Brinell (HB) max | ||||
| F91 | 585 | 415 | 20 | – | 248 max |
| STANDARD | UNS | WERKSTOFF NR. |
|---|---|---|
| Alloy Steel F91 | K90901 | 1.4903 |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
|
Pipe Normal Diam. |
O.D. Flange |
Thk. Of Flange Min |
Diam.
of
Hub |
Diameter of Raised Face |
Length Hub.Y |
Thread Length |
Diam.
of Bolt
Circle |
Diam.
of Bolt
Holes |
Number
of Bolts |
Diam. of
Bolts
(inch) |
KG |
LB |
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
inch |
dn |
O |
C |
X |
G |
Y |
T |
BC |
BH |
BN |
BD |
||
|
1/2″ |
15 |
89.00 |
11.20 |
30.20 |
35.10 |
15.70 |
15.70 |
60.50 |
15.80 |
4 |
1/2″ |
0.4 |
0.9 |
|
3/4″ |
20 |
98.50 |
12.70 |
38.10 |
42.90 |
15.70 |
15.70 |
69.90 |
15.80 |
4 |
1/2″ |
0.7 |
1.5 |
|
1″ |
25 |
108.00 |
14.20 |
49.30 |
50.80 |
17.50 |
17.50 |
79.30 |
15.80 |
4 |
1/2″ |
0.8 |
1.8 |
|
1-1/4″ |
32 |
117.50 |
15.70 |
58.70 |
63.50 |
20.60 |
20.60 |
88.90 |
15.80 |
4 |
1/2″ |
1.2 |
2.6 |
|
1-1/2″ |
40 |
127.00 |
17.50 |
65.00 |
73.20 |
22.40 |
22.40 |
98.60 |
15.80 |
4 |
1/2″ |
1.5 |
3.3 |
|
2″ |
50 |
152.50 |
19.10 |
77.70 |
91.90 |
25.40 |
25.40 |
120.70 |
19.10 |
4 |
5/8″ |
2.3 |
5.1 |
|
2-1/2″ |
65 |
178.00 |
22.40 |
90.40 |
104.60 |
28.40 |
28.40 |
139.70 |
19.10 |
4 |
5/8″ |
3.7 |
8.1 |
|
3″ |
80 |
190.50 |
23.90 |
108.00 |
127.00 |
30.20 |
30.20 |
152.40 |
19.10 |
4 |
5/8″ |
4.1 |
9 |
|
3-1/2″ |
90 |
216.00 |
23.90 |
122.20 |
139.70 |
31.80 |
31.80 |
177.80 |
19.10 |
8 |
5/8″ |
5.1 |
11.2 |
|
4″ |
100 |
228.50 |
23.90 |
134.90 |
157.20 |
33.30 |
33.30 |
190.50 |
19.10 |
8 |
5/8″ |
5.9 |
13 |
|
5″ |
125 |
254.00 |
23.90 |
163.60 |
185.70 |
36.60 |
36.60 |
215.90 |
22.40 |
8 |
3/4″ |
7 |
15.4 |
|
6″ |
150 |
279.50 |
25.40 |
192.00 |
215.90 |
39.60 |
39.60 |
241.30 |
22.40 |
8 |
3/4″ |
8.4 |
18.5 |
|
8″ |
200 |
343.00 |
28.40 |
246.10 |
269.70 |
44.50 |
44.50 |
298.50 |
22.40 |
8 |
3/4″ |
13 |
28.6 |
|
10″ |
250 |
406.50 |
30.20 |
304.80 |
323.90 |
49.30 |
49.30 |
362.00 |
25.40 |
12 |
7/8″ |
18 |
39.5 |
|
12″ |
300 |
482.50 |
31.80 |
365.30 |
381.00 |
55.60 |
55.60 |
431.80 |
25.40 |
12 |
7/8″ |
29 |
64 |
|
14″ |
350 |
533.50 |
35.10 |
400.10 |
412.80 |
57.20 |
57.20 |
476.30 |
28.50 |
12 |
1″ |
39 |
86 |
|
16″ |
400 |
597.00 |
36.60 |
457.20 |
469.90 |
63.50 |
63.50 |
539.80 |
28.50 |
16 |
1″ |
47 |
103 |
|
18″ |
450 |
635.00 |
39.60 |
505.00 |
533.40 |
68.30 |
68.30 |
577.90 |
31.80 |
16 |
1 1/8″ |
57 |
126 |
|
20″ |
500 |
698.50 |
42.90 |
558.80 |
584.20 |
73.20 |
73.20 |
635.00 |
31.80 |
20 |
1 1/8″ |
76 |
167 |
|
24″ |
600 |
813.00 |
47.80 |
663.40 |
692.20 |
82.60 |
82.60 |
749.30 |
35.10 |
20 |
1 1/4″ |
97 |
214 |
Luke Steel is a top manufacturer and supplier of high-quality Alloy Steel F91 Flanges products in Houstan, USA. Specializing in steel solutions, we provide a wide range of products, including Carbon Steel, Alloy Steel, Mild Steel and Galvanized Steel. Our offerings include Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets and Plates. Known for our reliable delivery and superior customer service, we are committed to offering top-tier steel materials that ensure durability and performance across a wide range of industrial applications. We strive to meet the highest standards, making us a trusted partner for all your steel needs.
F91 Flanges are often used in steam, gas, and water lines in thermal and nuclear power plants, where high-temperature strength and pressure resistance are essential. They are also applied in the petrochemical industry, refining, and natural gas pipelines, where prolonged exposure to high temperatures and harsh chemicals is common. F91’s excellent mechanical properties make it suitable for high-stress connections in heat exchangers, reactors, and turbine components. Luke Steel offers flanges in various sizes and configurations, ensuring precise fittings and leak-proof performance in critical infrastructure across industries requiring safe and reliable connections.
Luke Steel is a leading manufacturer, supplier and exporter of high-quality Carbon Steel, Alloy Steel, Mild Steel and Galvanized Steel products. Our extensive product range includes Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets and Plates, catering to various industries in Houstan, USA.
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