Tesco Steel & Engineering manufactures self reinforced nozzles (self-reinforced nozzle flanges) — vessel nozzles whose reinforcement is built into the forging itself, so no separate reinforcing pad is welded on. The extra metal of the integral hub replaces the area removed by the opening, and all welds between the nozzle and the components are full-penetration (full insertion) welds. The result is a cleaner, stronger, easier-to-inspect nozzle for pressure vessels and tanks. Made to ASME Section VIII & B16.5 in A105, SS 304/316/321, Duplex, Monel, Inconel, and Hastelloy. Class 150 to 2500, PN1 to PN400. ISO 9001:2015 certified. Made in India.
Self Reinforced Nozzle Flange
Self reinforced nozzles are the integrally-reinforced answer to vessel openings — the same principle as a flangeolet / weldo flange branch outlet, applied to vessel nozzles. Tesco Steel & Engineering manufactures them to drawing in the full material range — see our special products and flange dimensions charts.
| Criterion | Self Reinforced Nozzle | Pad-Reinforced Nozzle |
|---|---|---|
| Reinforcement | Integral (forged into the nozzle) | Separate reinforcing pad welded on |
| Welds | Full-penetration, fewer welds | Fillet welds around the pad |
| Crevices | None (no pad gap) | Crevice under the pad (telltale hole) |
| Inspection | Easy to radiograph & inspect | Harder; pad obscures welds |
| Fatigue / cyclic | Superior | Lower (weld toes at the pad) |
| Best for | Cyclic, high-temp, lethal, critical service | General & lower-duty openings |
| Self Reinforced Nozzle Flanges are available in the following specifications: | |
|---|---|
| Size | 1/2"NB to 56"NB |
| Class | 150#, 300#, 3000#, 6000#, 9000# |
| Sch (Schedule) | XS, XXS, STD & Schedule 20, 40, 80, 160 |
| Pressure Ratings | PN 1 - PN 400 |
| Stainless Steel Self Reinforced Nozzle Flanges | ASTM A 182 F - 304 / 304H / 304L / 316 / 316H / 316L / 316Ti, 309, 310, 317L, 321, 347, 904L |
| Duplex Steel Self Reinforced Nozzle Flanges | ASTM A 182 - F 51, F 53, F 55 |
| Alloy Steel Self Reinforced Nozzle Flanges | ASTM A 182 - F5, F9, F11, F21, F22 & F91 |
| Carbon Steel Self Reinforced Nozzle Flanges | ASTM A 105 |
| Low Temp. Carbon Steel Self Reinforced Nozzle Flanges (LTCS Self Reinforced Nozzle Flanges) | A 350 LF2 |
| Copper Nickel (Cu-Ni) Self Reinforced Nozzle Flanges | C70600, 90/10, C71500, 70/30, C71640 |
| Nickel Self Reinforced Nozzle Flanges | UNS N02200, UNS N02201 |
| Monel Self Reinforced Nozzle Flanges | UNS N04400, UNS N05500, Alloy 20 |
| Inconel Self Reinforced Nozzle Flanges | UNS N06600, UNS N06601, UNS N06625, UNS N08800, UNS N08810, UNS N08825 |
| Hastelloy Self Reinforced Nozzle Flanges | UNS N10276, UNS N06022, UNS N10665, UNS N06455 |
| Titanium Self Reinforced Nozzle Flanges | Gr. 1, Gr. 2, Gr. 3, DTH 3.7035, DTH 3.7055 |
| Other Services | Hot Dip Galvanized (GI) Self Reinforced Nozzle Flanges Sand Blasting on Self Reinforced Nozzle Flanges Shot Peening on Self Reinforced Nozzle Flanges Epoxy Coating on Self Reinforced Nozzle Flanges FBE Coating on Self Reinforced Nozzle Flanges |
Reinforcement forged into the nozzle — no separate pad — satisfying ASME VIII area-replacement in one piece.
Full-insertion welds with no hidden roots or pad crevices, easy to radiograph and inspect.
A105, LTCS, SS 304/316/321, Duplex, Monel, Inconel, and Hastelloy for corrosive & high-temperature vessels.
Smooth integral geometry lowers stress concentration for cyclic, high-temperature, and lethal service.
RF / RTJ faces to ASME B16.5 so the nozzle bolts up to standard mating flanges and gaskets.
Designed and forged to your vessel/nozzle drawing and ASME Section VIII requirements, certified with EN 10204 3.1 MTC.
| Material | Properties | Typical Use |
|---|---|---|
| A105 Carbon Steel / A350 LF2 (LTCS) | Strong, economical; LF2 for low temp | General & low-temperature vessels |
| SS 304 / 316 / 321 | Good corrosion resistance; 321 high-temp | Process, chemical & high-temperature vessels |
| Duplex 2205 / Super Duplex 2507 | High strength & chloride resistance | Offshore & seawater vessels |
| Monel 400 / Inconel | Excellent in HF, marine & high-temp | HF, seawater & high-temperature service |
| Hastelloy | Superior acid resistance | Aggressive chemical vessels |
| Industry | Typical Use | Why Self Reinforced Nozzle |
|---|---|---|
| Oil & Gas | Pressure-vessel & separator nozzles | No pad; full-penetration; sour-service alloys |
| Refinery & Petrochemical | Reactor, column & drum nozzles | Cyclic / high-temp fatigue performance |
| Power Generation | Boiler-drum & HP vessel nozzles | Easy radiography; SS 321 / alloy steel |
| Chemical Plants | Lethal & corrosive-service vessels | No crevice; Monel / Inconel / Hastelloy |
| LNG & Cryogenic | Low-temperature vessel nozzles | LTCS / SS; clean integral welds |
| Fertilizer & Process | High-pressure reactor nozzles | Integral reinforcement to Class 2500 |
| Offshore & Marine | Topside vessel nozzles | Duplex; lightweight, no pad |
| Pharmaceutical | Hygienic vessel nozzles | Crevice-free SS 316 nozzles |
Q1. What is a self reinforced nozzle?
A self reinforced nozzle is a vessel nozzle whose reinforcement is forged into the nozzle itself, so it needs no separate reinforcing pad. The integral hub provides the extra metal to replace the area removed by the opening, and all the welds between the nozzle and the vessel/flange are full-penetration (full-insertion) welds. It is used on pressure vessels and tanks, especially for critical service.
Q2. How is a self reinforced nozzle different from a pad-reinforced nozzle?
A pad-reinforced nozzle has a separate reinforcing pad fillet-welded around it, which creates a crevice (with a telltale hole) and weld toes that obscure inspection and reduce fatigue life. A self reinforced nozzle builds the reinforcement into the forging with full-penetration welds and no pad — cleaner, easier to inspect, and better for cyclic and high-temperature service.
Q3. Why use a self reinforced nozzle?
Because it has no pad crevice, fewer welds, full-penetration welds that can be fully radiographed, lower stress concentration, and better fatigue performance. This makes it the preferred nozzle for cyclic, high-temperature, lethal, and other critical vessel service, and it is lighter than a padded nozzle.
Q4. Does a self reinforced nozzle meet ASME code reinforcement rules?
Yes. The integral metal of the nozzle is sized so it satisfies the ASME Section VIII area-replacement requirement for the opening, replacing the role of a pad. The nozzle is designed for the shell thickness, opening size, and design pressure/temperature, with full-penetration welds and the required NDT.
Q5. What welds are used on a self reinforced nozzle?
Full-penetration (full-insertion) welds between the nozzle and the shell and between the nozzle and the flange, rather than the fillet welds used to attach a reinforcing pad. Full-penetration welds give full strength and no hidden roots, and can be radiographed for critical service.
Q6. What classes, facings, and materials are available?
Class 150 to 2500 and PN1 to PN400, with RF or RTJ facings to ASME B16.5, in A105/LTCS, SS 304/316/321, Duplex, Monel, Inconel, and Hastelloy. The class, facing, and material are chosen for the vessel service and the mating flange.
Q7. Is a self reinforced nozzle the same idea as a flangeolet?
They share the principle of integral (self) reinforcement. A flangeolet / weldo flange is a self-reinforced branch outlet on a run pipe, while a self reinforced nozzle is the integrally-reinforced opening on a pressure vessel or tank. Both replace a separate reinforcing pad with built-in reinforcement.
Q8. Can self reinforced nozzles be supplied to our drawing and certified?
Yes. We design and forge self reinforced nozzles to your vessel/nozzle drawing and ASME Section VIII requirements — size, class, facing, material, and weld detail — with EN 10204 3.1 material test certificates and the specified NDT on request. Send your vessel data for a recommendation and quote.