Thabiso Steel, a prominent manufacturer and supplier located in Cape Town, South Africa, specializes in top-notch **Alloy Steel P91 Pipes** that are engineered for high-temperature, high-pressure, and heavy-duty industrial applications. These pipes are crafted with precision to provide outstanding strength, creep resistance, and durability, ensuring they perform reliably even in the toughest conditions. Adhering to international standards, Thabiso Steel promises consistent mechanical performance and a long lifespan. Catering to sectors like power generation, petrochemical, and oil and gas, the company offers Alloy Steel P91 Pipes that blend operational efficiency, structural integrity, and toughness, making them a go-to choice for critical industrial piping needs throughout South Africa.
**Alloy Steel P91 Pipes** are made from high-quality alloy steel, with carefully balanced amounts of chromium, molybdenum, and vanadium to boost tensile strength, hardness, and creep resistance at high temperatures. These pipes showcase impressive yield and tensile strength, excellent impact resistance, and stability in high-pressure and high-temperature situations. Their fine-grain microstructure ensures they are weldable, tough, and durable over the long haul, making Alloy Steel P91 Pipes perfect for demanding applications in power generation, petrochemical, and other industries that require superior mechanical and thermal properties.
| 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.
ThabisoSteel is a major manufacturer and a supplier of premium Alloy Steel P91 pipe in Cape Town, the South Africa. 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 |
**Alloy Steel P91 Pipes** are extensively utilized in sectors that need strong, heat-resistant, and durable piping solutions. They’re commonly found in power plant boilers, steam pipelines, petrochemical facilities, and oil and gas refineries. Moreover, they are essential in high-pressure piping systems, industrial machinery, and structural frameworks where creep resistance, toughness, and thermal stability are vital. The combination of mechanical strength, corrosion resistance, and long-term reliability ensures safe and efficient operation, making Alloy Steel P91 Pipes the ideal choice for demanding industrial applications.





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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