Filiz Steel, based in Istanbul, Turkey, stands out as a top manufacturer and supplier of premium steel products, with a focus on industrial flanges and alloy components. One of their standout products is the Alloy Steel F91 Flanges, crafted to deliver outstanding strength, durability, and thermal stability for tough applications. These flanges are produced using cutting-edge techniques and rigorous quality checks, ensuring they meet international standards for both mechanical and chemical performance. With Filiz Steel’s expertise, every Alloy Steel F91 Flange is built for reliability, making them perfect for sectors like power generation, petrochemicals, oil and gas, and heavy industry—where high-performance flanges are essential for safety, efficiency, and long-lasting operation.
The Alloy Steel F91 Flanges are made from a high-quality alloy that includes chromium, molybdenum, vanadium, and carbon, all designed to provide exceptional strength, toughness, and resistance to creep. They undergo careful heat treatment to boost hardness, tensile strength, and resistance to fatigue and thermal stress. Thanks to their excellent dimensional stability and consistent mechanical properties, including high yield and tensile strength, these flanges maintain their structural integrity even in extreme temperatures and high-pressure situations. Filiz Steel’s thorough manufacturing process guarantees top-notch quality, making them perfect for critical industrial piping and mechanical applications.
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 |
Filiz Steel is a top manufacturer and supplier of high-quality Alloy Steel F91 Flanges products in Istanbul, Turkey. 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.
Filiz Steel’s Alloy Steel F91 Flanges are commonly found in power plants, petrochemical facilities, oil and gas pipelines, and high-temperature industrial equipment. They’re ideal for connecting piping systems, pressure vessels, heat exchangers, and other components that face intense heat and stress. With their remarkable mechanical strength, thermal resistance, and durability, these flanges are designed for applications that demand long-term creep and fatigue resistance. They ensure leak-proof and dependable performance in even the most challenging environments.
Filiz 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 Istanbul, Turkey.
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