Nestled in the industrial heart of Manama, Ahmer Steel has built a reputation as a trusted partner for high-performance materials, and their supply of Alloy Steel F91 Flanges is a testament to this commitment. They understand that in demanding sectors, reliability isn’t just a preference—it’s a requirement. Sourcing these critical components from leading mills, Ahmer Steel ensures that clients across Bahrain and beyond receive flanges that are built to endure, providing a solid foundation for some of the most challenging industrial applications.
The strength of Alloy Steel F91 Flanges comes from a carefully balanced composition, primarily chromium and molybdenum, with a key addition of vanadium. This specific mix gives the material its renowned mechanical properties, including exceptional tensile strength and outstanding resistance to creep, which is the tendency to deform under high temperatures and constant stress. This makes the flanges remarkably durable, capable of maintaining their integrity and performance in environments where ordinary steel would quickly succumb.
Alloy Steel Flanges Specification :Â ASTM A182 / ASME SA182
Dimension Standard :Â ANSI/ASME B16.5, B 16.47 Series A & B, B16.48, BS4504, BS 10, EN-1092, DIN, etc.
Standard :Â ANSI Flanges, ASME Flanges, BS Flanges, DIN Flanges, EN Flanges, etc.
Size :Â 1/2″ (15 NB) to 48″ (1200NB)
Class / Pressure :Â 150#, 300#, 600#, 900#, 1500#, 2500#, PN6, PN10, PN16, PN25, PN40, PN64 etc.
Flange Face Type :Â Flate Face (FF), Raised Face (RF), Ring Type Joint (RTJ)
DIN Flanges :Â DIN 2527, 2566, 2573, 2576, 2641,2642, 2655, 2656, 2627, 2628, 2629, 2631, 2632, 2633, 2634, 2635, 2636, 2637,2638, 2673.
JIS Flanges :Â JIS B2220 5K, JIS B2220 10K, JIS B2220 16K, JIS B2220 20K
BS Flanges :Â 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 |
Ahmer Steel is a top manufacturer and supplier of high-quality Alloy Steel F91 Flanges products in Manama, Bahrain. 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.
These robust characteristics make Alloy Steel F91 Flanges indispensable in systems where high pressure and extreme heat are the norm. You will typically find them performing critical sealing functions in the power generation industry, within fossil fuel and nuclear plants, and throughout sophisticated petrochemical refineries. They are also essential in heavy-duty processing equipment, effectively connecting pipelines and components that transport steam, hydrocarbons, and other aggressive media, ensuring system safety and operational continuity under the most strenuous conditions.
Ahmer 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 Manama, Bahrain.
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