Filiz Steel, located in Istanbul, Turkey, stands out as a top manufacturer and supplier of high-quality Alloy Steel P91 Pipes. Renowned for its precision engineering and commitment to international standards, Filiz Steel crafts pipes that offer remarkable strength, durability, and reliability, even in the toughest industrial settings. These pipes are made from premium-grade alloy steel and utilize advanced heat treatment and fabrication techniques, ensuring they perform exceptionally well under high pressure and elevated temperatures. Trusted by industries such as power generation, petrochemical, oil and gas, and chemical processing, Filiz Steel guarantees that its P91 Pipes deliver long-lasting, safe, and efficient solutions for critical piping systems around the globe.
Alloy Steel P91 Pipes are primarily made up of chromium and molybdenum, with carefully controlled amounts of carbon, manganese, and vanadium to boost their strength, hardness, and resistance to creep. These pipes showcase impressive tensile and yield strength, outstanding toughness, and stability at high temperatures. Thanks to advanced heat treatment processes like normalizing and tempering, their mechanical properties are further enhanced, ensuring they remain durable and structurally sound even under extreme conditions. With a well-balanced chemical composition and a refined microstructure, Alloy Steel P91 Pipes consistently perform well, making them ideal for high-stress, high-temperature industrial applications that demand a long service life.
| Type | Seamless / ERW / Welded / Fabricated |
| Standard | ASTM A335 P91, SA335 P91 (with IBR Test Certificate) |
| Size | 1/2” NB to 36” NB |
| Length | Standard Double & In Cut length also. |
| Schedules | SCH 40, SCH 80, SCH 160, SCH XS, SCH XXS, All Schedules |
| Tolerance | Cold drawn pipe: +/-0.1mm
Cold rolled pipe: +/-0.05mm |
| Application | Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service |
| End | Plain End, Beveled End, Treaded |
| Craft | Cold rolled and Cold drawn |
| available in Form of | Round, Square, Rectangular, Hydraulic Etc. |
| Origin | European, Japanese, Korean, US, Russian, Indian (Strictly No Chinese Material) |
| Specialized in | Large Diameter ASTM A335 P91 Pipe |
| Additional Testing | NACE MR 0175, NACE TM0177, NACE TM0284, HIC TEST, SSC TEST, H2 SERVICE, IBR, etc. |
| Thickness | 3-12mm |
| Alloy Steel P91 | C | Cr | Mn | Mo | P | S | Si |
| 0.08-0.12 | 8.00 – 9.50 | 0.30-0.60 | 0.85 – 1.05 | 0.020 max | 0.010 max | 0.20 -0.50 |
| Tensile Strength, MPa | Yield Strength, MPa | Elongation |
| 585 min | 415 min | 20 min |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
Filiz Steel is a major manufacturer and a supplier of premium Alloy Steel P91 pipe in Istanbul, the Turkey. With specialization in steel solutions, we offer a variety of products including carbon steel, alloy steel, light steel and galvanized steel. Our wide bearing has pipes, pipes, flanges, pipe fittings, forged fittings, sheets and plates. We are famous for our reliable distribution and extraordinary customer service, and are committed to offering high quality steel materials that ensure durability and better performance in different industrial applications. We are committed to skill, and we are your reliable partners for all steel requirements.
| ASTM | ASME | Equivalent material | JIS G 3458 | UNS | BS | DIN | ISO | ABS | NK | LRS |
|---|---|---|---|---|---|---|---|---|---|---|
| A335 P91 | SA335 P91 | T91, K90901, X10CrMoVNb9-1, 1.4903 | K91560 |
| O.D.(mm) x Thickness(mm) | O.D(mm) x Thickness(mm) | O.D(mm) x Thickness(mm) |
|---|---|---|
| 38.1 x 3.2 | 57.0 x 4.9 | 76.2 x 4.0 |
| 38.1 x 4.0 | 57.0 x 6.3 | 76.2 x 5.0 |
| 38.1 x 6.3 | 57.0 x 7.9 | 76.2 x 6.3 |
| 42.4 x 3.2 | 60.3 x 3.2 | 82.5 x 4.5 |
| 42.4 x 4.0 | 60.3 x 3.6 | 88.9 x 3.2 |
| 44.5 x 3.2 | 60.3 x 5.0 | 88.9 x 3.6 |
| 44.5 x 6.3 | 63.5 x 3.2 | 88.9 x 4.0 |
| 48.3 x 3.2 | 63.5 x 3.6 | 101.6 x 3.6 |
| 48.3 x 3.6 | 63.5 x 4.0 | 101.6 x 4.5 |
| 50.8 x 4.5 | 63.5 x 6.3 | 101.6 x 6.3 |
| 51.0 x 3.2 | 63.5 x 7.9 | 114.3 x 3.6 |
| 51.0 x 3.6 | 70.0 x 3.2 | 114.3 x 5.0 |
| 51.0 x 6.3 | 70.0 x 3.6 | 139.7 x 4.0 |
| 57.0 x 3.2 | 70.0 x 6.3 | 139.7 x 5.0 |
| 57.0 x 3.6 | 76.2 x 3.6 | 139.7 x 6.3 |
| Size NPS | Pipe O.D. | Wall Thickness | Pipe I.D. | Weight per Foot | Standard to XXHY | Schedule Pipe # | Section Modulus | Gallon Capacity Per Linear Foot |
| 1/2 | 0.84 | 0.109 | 0.622 | 0.85 | STD | 40 | .0407 | .0158 |
| 0.147 | 0.546 | 1.09 | XHY | 80 | .0478 | .0122 | ||
| 0.188 | 0.464 | 1.31 | 160 | .0528 | .0088 | |||
| 0.294 | 0.252 | 1.72 | XXHY | .0577 | .0026 | |||
| 3/4 | 1.05 | 0.113 | 0.824 | 1.13 | STD | 40 | .0705 | .0277 |
| 0.154 | 0.742 | 1.48 | XHY | 80 | .0853 | .0225 | ||
| 0.219 | 0.612 | 1.95 | 160 | .1006 | .0153 | |||
| 0.308 | 0.434 | 2.44 | XXHY | .1103 | .0077 | |||
| 1 | 1.315 | 0.133 | 1.049 | 1.68 | STD | 40 | .1328 | .0449 |
| 0.179 | 0.957 | 2.17 | XHY | 80 | .1606 | .0374 | ||
| 0.250 | 0.815 | 2.85 | 160 | .1904 | .0271 | |||
| 0.358 | 0.599 | 3.66 | XXHY | .2136 | .0146 | |||
| 1 1/4 | 1.66 | 0.140 | 1.380 | 2.27 | STD | 40 | .2346 | .0777 |
| 0.191 | 1.278 | 3.00 | XHY | 80 | .2913 | .0666 | ||
| 0.250 | 1.160 | 3.77 | 160 | .3421 | .0549 | |||
| 0.382 | 0.896 | 5.22 | .4110 | .0328 | ||||
| 1 1/2 | 1.90 | 0.145 | 1.610 | 2.72 | STD | 40 | .3262 | .1058 |
| 0.200 | 1.500 | 3.63 | XHY | 80 | .4118 | .0918 | ||
| 0.281 | 1.338 | 4.86 | 160 | .5079 | .0730 | |||
| 0.400 | 1.100 | 6.41 | .5977 | .0494 | ||||
| 2 | 2.375 | 0.109 | 2.157 | 2.64 | 10 | .4205 | .1898 | |
| 0.154 | 2.067 | 3.66 | STD | 40 | .5606 | .1743 | ||
| 0.218 | 1.939 | 5.03 | XHY | 80 | .7309 | .1534 | ||
| 0.250 | 1.875 | 5.68 | .8045 | .1434 | ||||
| 0.281 | 1.813 | 6.29 | .8666 | .1344 | ||||
| 0.344 | 1.687 | 7.47 | 160 | .9806 | .1161 | |||
| 0.436 | 1.503 | 9.04 | XXHY | 1.1043 | .0922 | |||
| 2 1/2 | 2.875 | 0.120 | 2.635 | 3.53 | 10 | .6870 | .2833 | |
| 0.203 | 2.469 | 5.80 | STD. | 40 | 1.0640 | .2487 | ||
| 0.216 | 2.443 | 6.14 | 1.1169 | .2435 | ||||
| 0.250 | 2.375 | 7.02 | 1.2468 | .2301 | ||||
| 0.276 | 2.323 | 7.67 | XHY | 80 | 1.3386 | .2202 | ||
| 0.375 | 2.125 | 10.02 | 160 | 1.6371 | .1842 | |||
| 0.552 | 1.771 | 13.71 | XXXHY | 1.9971 | .1280 | |||
| 3 | 3.50 | 0.120 | 3.260 | 4.34 | 1.0411 | .4336 | ||
| 0.156 | 3.188 | 5.58 | 1.3122 | .4147 | ||||
| 0.172 | 3.156 | 6.12 | 1.4265 | .4064 | ||||
| 0.188 | 3.124 | 6.66 | 1.5342 | .3984 | ||||
| 0.216 | 3.068 | 7.58 | STD. | 40 | 1.7241 | .3840 | ||
| 0.250 | 3.000 | 8.69 | 1.9372 | .3672 | ||||
| 0.281 | 2.938 | 9.67 | 2.1207 | .3521 | ||||
| 0.300 | 2.900 | 10.26 | XHY | 80 | 2.2253 | .3431 | ||
| 0.438 | 2.624 | 14.34 | 160 | 2.8774 | .2811 | |||
| 0.600 | 2.300 | 18.6 | XXHY | 3.4243 | .2158 | |||
| 3 1/2 | 4.0 | 0.120 | 3.760 | 4.98 | 10 | 1.3776 | .5768 | |
| 0.226 | 3.548 | 9.12 | STD. | 140 | 2.3939 | .5136 | ||
| 0.250 | 3.500 | 10.02 | 2.6001 | .4998 | ||||
| 0.281 | 3.438 | 11.17 | 2.8562 | .4821 | ||||
| 0.318 | 3.364 | 12.52 | XHY | 80 | 3.1400 | .4617 | ||
| 0.636 | 2..728 | 22.87 | XXHY | 4.8795 | .3085 | |||
| 4 | 4.5 | 0.120 | 4.260 | 5.62 | 10 | 1.7612 | .7404 | |
| 0.156 | 4.188 | 7.24 | 2.2354 | .7156 | ||||
| 0.188 | 4.124 | 8.67 | 2.6296 | .6942 | ||||
| 0.203 | 4.094 | 9.32 | 2.8173 | .6838 | ||||
| 0.219 | 4.062 | 10.02 | 3.0184 | .6725 | ||||
| 0.237 | 4.026 | 10.80 | STD. | 40 | 3.2145 | .6613 | ||
| 0.250 | 4.000 | 11.36 | 3.3611 | .6528 | ||||
| 0.281 | 3.938 | 12.67 | 60 | 3.7021 | .6326 | |||
| 0.312 | 3.876 | 13.97 | 4.0273 | .6126 | ||||
| 0.337 | 3.826 | 15.00 | XHY | 80 | 4.2713 | .5972 | ||
| 0.438 | 3.624 | 19.02 | 120 | 5.1790 | .5361 | |||
| 0.531 | 3.438 | 22.53 | 160 | 5.8997 | .4822 | |||
| 0.674 | 3.152 | 27.57 | XXHY | 6.7927 | .4054 | |||
| 5 | 5.563 | 0.188 | 5.187 | 10.80 | 4.1161 | 1.0979 | ||
| 0.219 | 5.125 | 12.51 | 4.7279 | 1.0716 | ||||
| 0.258 | 5.047 | 14.63 | STD. | 40 | 5.4500 | 1.0391 | ||
| 0.281 | 5.001 | 15.87 | 5.8644 | 1.0204 | ||||
| 0.312 | 4.939 | 17.51 | 6.4074 | .99647 | ||||
| 0.344 | 4.875 | 19.19 | 6.9358 | .9696 | ||||
| 0.375 | 4.813 | 20.80 | XHY | 80 | 7.4300 | .9449 | ||
| 0.500 | 4.563 | 27.06 | 120 | 9.2534 | .8495 | |||
| 0.625 | 4.313 | 32.99 | 160 | 10.7976 | .7590 | |||
| 0.750 | 4.063 | 38.59 | XXHY | 12.0954 | .6734 | |||
| 6 | 6.625 | 0.109 | 6.407 | 7.59 | 5 | 3.5769 | 1.6748 | |
| 0.134 | 6.357 | 9.30 | 10 | 4.3475 | 1.6488 | |||
| 0.156 | 6.313 | 10.79 | 5.0107 | 1.6260 | ||||
| 0.188 | 6.249 | 12.94 | 5.9351 | 1.5937 | ||||
| 0.203 | 6.219 | 13.94 | 6.3804 | 1.5780 | ||||
| 0.219 | 6.187 | 15.00 | 6.8261 | 1.5620 | ||||
| 0.250 | 6.125 | 17.04 | 7.6905 | 1.5306 | ||||
| 0.280 | 6.065 | 18.99 | STD. | 40 | 8.4958 | 1.5008 | ||
| 0.312 | 6.001 | 21.06 | 9.3416 | 1.4688 | ||||
| 0.344 | 5.937 | 23.10 | 10.111 | 1.4391 | ||||
| 0.375 | 5.875 | 25.05 | 10.893 | 1.4082 | ||||
| 0.432 | 5.761 | 28.60 | XHY | 80 | 12.224 | 1.3541 | ||
| 0.500 | 5.625 | 32.74 | 13.711 | 1.2909 | ||||
| 0.562 | 5.501 | 36.43 | 120 | 14.9806 | 1.2346 | |||
| 0.625 | 5.375 | 40.09 | 16.1821 | 1.1787 | ||||
| 0.719 | 5.187 | 45.39 | 160 | 17.8243 | 1.0977 | |||
| 0.864 | 4.897 | 53.21 | XXHY | 20.025 | .9784 | |||
| 1.000 | 4.625 | 60.13 | 21.7719 | .8727 | ||||
| 1.125 | 4.375 | 66.14 | 23.1237 | .7809 |
These pipes are widely utilized in sectors where resistance to high temperatures and pressures is essential. They’re commonly found in power plants, oil and gas refineries, petrochemical facilities, and chemical processing units. Perfect for use in boilers, superheaters, heat exchangers, and pressure vessels, these pipes guarantee safe and efficient operation in challenging environments. Their ability to resist creep, oxidation, and thermal stress makes them a reliable choice for long-term service in critical applications. Filiz Steel’s Alloy Steel P91 Pipes are designed to provide dependable and efficient solutions for the most demanding industrial needs.





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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