Weldoflange & Nipoflange | MSS SP-97 | ASME B16.5
PM Industries manufactures, supplies, and stocks Weldo Nipo Flanges in a range of materials, pressure classes, and pipe size combinations. A Weldo flange, also called a Weldo flange or nipo flange, is a single forged component that combines a branch outlet fitting (the weldolet or nipolet body) with an integral flange face. It welds directly onto the outside of the run pipe at a branch location, providing a reinforced branch outlet and a flanged connection in one piece, without requiring a separate branch fitting, pipe nipple, and flange to be assembled in sequence.
The comparison to the conventional branch-plus-flange assembly is the clearest way to understand where weldo nipo flanges add value. A standard branch connection using a weldolet requires welding the weldolet to the run pipe, then welding a nipple to the weldolet outlet, then welding or threading a flange to the nipple. That's three components and multiple welds to achieve what a weldo flange accomplishes in one forged piece and two welds: the branch-to-run pipe weld and the contour weld at the base of the fitting. Fewer components, fewer welds, shorter installed length, and less inspection work.
Weld count reduction matters in high-integrity piping systems where every weld is a radiographic or ultrasonic inspection point. In a critical piping class where full inspection of branch connection welds is required, eliminating a nipple-to-weldolet weld and a nipple-to-flange weld at each branch location reduces the inspection scope meaningfully. On a project with many branch connections, that reduction accumulates across the system.
Installed length at the branch connection is shorter than a sequential assembly. In congested equipment rooms, compressor skids, and offshore module piping where space between run pipe and adjacent structure or equipment is limited, the reduced face-to-face dimension of a weldo flange may be the difference between a layout that works and one that requires rerouting or custom offset fittings.
Instrumentation and chemical injection connections are typical small-bore weldo flange applications. Pressure taps, thermowell connections, sample connections, and chemical dosing points in high-pressure piping often use weldo flanges to provide a flanged branch outlet directly on the main run pipe without requiring a full branch assembly that would extend further into the available space.
Weldo nipo flanges are available with full material certification to ASTM, ASME, and applicable specifications including NACE MR0175 for sour service. Contact PM Industries for run pipe size, branch size, material grade, pressure class, face type, and pricing.
Specification Nipo Flange
| Standards | ANSI/ASME B16.5, B16.48, GOST, DIN, EN-1092, B16.47 Series A & B, AWWA, BS Flanges |
| JIS Standard | 5K, 10K, 16K, 20K, 30K, 40K, 63K |
| DIN Flanges | DIN 2527, 2627, 2631, 2656, 2576, 2673, 2629, 2628, 2566 |
Flanges are Available in Following Materials
| Stainless Steel | SS 201, SS 202, SS 301, SS 304, SS 304L, SS 310, SS 310S, SS 316L, SS 316TI, SS 317, SS 317L, SS 321, SS 347, SS 409, SS 409M, SS 409L, SS 410, SS 410S, SS 420, SS 430, SS 431, SS 441, SS 444, SS 446, SS 17-4PH, SS 904L. |
| Duplex Steel | UNS S32205, UNS S31803 Flange |
| Super Duplex Steel | UNS S32750, UNS S32760 Flanges |
| Carbon Steel | Carbon steel A105 Flanges, A36 Flanges, IS 2062 Flanges, A350 LF2 Flanges, F42 Flanges, F52 Flanges, F56 Flanges, F60 Flanges, F65 Flanges, F70 Flanges, F80 Flanges, IBR flanges, A694 Flanges, SS400, SF440, ST37-2 Flanges, S235JrG2 Flanges, P250GH Flanges, C22.8 Flanges, etc. |
| Alloys Steel | Alloy 20, F1, F5, F9, F11, F22, F91 Flanges |
| Copper Alloys | Cu-Ni 70/30, Cu-Ni 90/10, C 24000, C 75700, C 51100, C 22000, C 27200, C 21000, C 26800, C 52100, C 77000, C 52000, C 11000, C 74500, C 23000, C 28000, C 12200, C 76400, C 51900, C 75400, C 26000, C 51000, C 10200, C 27000 |
| Nickel Alloys | Nickel 200, 201 |
| Inconel | Inconel 600, 601, 625, 718, 800, 825, X-750 |
| Monel | Monel 400, k500 |
| Hastelloy | Hastelloy C-22, C-276, C-4, X |
| Titanium | Grade 1, 4, 5(Ti 6Al-4V), 6(Ti 5Al-2.5Sn), 7, 11, 6Al-2Sn-4Zr-2Mo, Grade 12, 6Al-6V-25n, Grade 23(Ti 6AL-4V ELI), 8Ai-1Mo-1V, Grade 5 ELI, Grade 9(3Al-2.5V), 6Al-7Nb. |
| Aluminium | 6063, 1100, 6082 A96082, 1050, 2017, 2024 A92024, 7050 A97050, 5083 A95083, 2014A A92014, 2011 A92011, 6061 A96061 A86061, 5754, 7085, 2050, 7071 7020, 7178, 5052 A95052, 7150, 7075 A97075 A87075, 7575, 2219, 7175 |
| Pressure Rating | Class 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS |
| Types | Threaded, Plate, Screwed, Forged. |
| Supporting material | Gasket, Ring Joint, Flange Bolts |
| Size range | 1/2" (15 NB) to 48" (1200NB) DN10~DN5000 |
| High Temperature | Above 200°C (400°F) For Class 150 Or Above 400°C (750°F) |
| Low Temperature | Above -29 Degree C (−20°F) |
| Production technique | Forged, machined and Heat treated |
| Custom design | As per your drawing |
| Origin | Indian / USA / Korean / West Europe / Japan |
| Pressure Class | PN 6 TO PN 100 |
| Coating/Surface Treatment: | Zinc Plated, Anti-rust Paint, Oil Black Paint, Yellow Transparent, Cold and Hot Dip Galvanized. |
| European/African/Russian Standard Flanges | Available |
| Test | Direct-reading Spectrograph, X-ray detector, UItrasonic flaw detector, Magnetic particle detector, Hydrostatic testing machine. |
Marking Standard | Name of Manufacturer |
| Schedule | |
| Type of Flange Facing | |
| Pressure Class | |
| Nominal Pipe Size, etc | |
Test Certificates | EN 10204/3.1B, NACE MR0103, NACE MR0175 |
| Raw Materials Certificate | |
| 100% Radiography Test Report | |
| Third Party Inspection Report, etc |