Thabiso Steel, based in Cape Town, South Africa, stands out as a top manufacturer and supplier of high-quality steel products, catering to a diverse array of industrial sectors. Among their impressive lineup, the Alloy Steel F91 Flanges shine for their remarkable strength, durability, and precision engineering. Crafted with cutting-edge forging and machining techniques, these flanges adhere to strict international standards, ensuring reliability and performance. Thabiso Steel’s commitment to innovation, quality control, and customer satisfaction means that every Alloy Steel F91 Flange consistently delivers outstanding results, even in the most demanding environments across South Africa and beyond.
These flanges are primarily made from a blend of chromium, molybdenum, vanadium, and carbon, creating a strong alloy with excellent mechanical and chemical properties. The chromium boosts resistance to oxidation and corrosion, while molybdenum and vanadium enhance tensile strength, hardness, and creep resistance at elevated temperatures. With superior yield and tensile strength, excellent thermal stability, and remarkable fatigue resistance, these flanges are built to last. Their finely tuned microstructure ensures they can withstand high pressure and temperature, making them perfect for tough industrial applications.
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 |
ThabisoSteel is a top manufacturer and supplier of high-quality Alloy Steel F91 Flanges products in Cape Town, South Africa. 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.
Alloy Steel F91 Flanges find extensive use in power generation, oil and gas, petrochemical, and chemical processing industries. They are perfectly designed for connecting pipes, valves, and equipment in systems that manage high-pressure steam, gas, or fluid flow. Typical applications include boiler installations, heat exchangers, turbines, and pressure vessels. These flanges guarantee leak-proof connections and maintain their structural integrity, even under extreme operating conditions. Their exceptional strength, heat resistance, and corrosion protection make them a reliable choice for any challenging environment.
ThabisoSteel 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 Cape Town, South Africa.
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