Description
Traceable alloy butt-weld fitting
ASTM B366 Hastelloy C276 Concentric Reducer
A procurement-ready concentric butt-weld reducer in ASTM B366/B366M, UNS N10276 nickel-molybdenum-chromium alloy, supplied for severe chemical, acid, chlorine-related and pollution-control service with project-defined dimensions, wall, construction and inspection.
What is a Hastelloy C276 concentric reducer?
A concentric reducer provides a symmetrical change between two pipe diameters. It is widely used in vertical lines, pump discharge, process headers and services where maintaining a common centerline is appropriate.
Hastelloy C276 is the widely used trade-name description for UNS N10276. It is considered where strong resistance is required across selected oxidizing and reducing media, including aggressive chemical and pollution-control duties.
Technical specification
| Product type | Concentric butt-weld reducer |
|---|---|
| Material | ASTM B366/B366M, UNS N10276 nickel-molybdenum-chromium alloy |
| Material family | Nickel-molybdenum-chromium alloy |
| Dimensional basis | ASME B16.9 or approved project drawing |
| Configuration | Concentric transition; larger and smaller ends on a common centerline |
| Nominal size | Standard ASME combinations and custom large/small-end combinations subject to review |
| Wall thickness | Standard schedules, heavy wall and project-specific wall subject to manufacturing review |
| Construction | Seamless or welded as applicable, ordered and permitted by the material class |
| End preparation | Butt-weld bevel matched to connecting pipe wall and approved welding detail |
| Heat treatment | Solution treatment and final condition as required by ASTM B366 and the ordered class |
| Documentation | EN 10204 3.1 MTC, heat traceability, PMI, dimensions and additional NDE as ordered |
Available size and wall combinations depend on alloy, forming route, construction and quantity. Confirm the exact pipe outside diameter and wall in the RFQ.
Standards and technical references
Dimensional standard
ASME B16.9 covers standard factory-made wrought butt-weld reducer dimensions, tolerances, marking and related requirements.
Material specification
ASTM B366/B366M covers factory-made wrought nickel and nickel-alloy pressure-piping fittings.
Why select Hastelloy C276?
UNS N10276 is considered for chemical reactors and transfer lines, acid systems, chlorination-related equipment, waste treatment and flue-gas desulfurization.
| Selection point | Hastelloy C276 | Alloy 20 |
|---|---|---|
| Alloy family | Ni-Mo-Cr severe-service alloy | Fe-Ni-Cr-Mo-Cu alloy |
| Typical focus | Broad severe chemical corrosion | Selected sulfuric-acid environments |
| Relative cost | Typically higher | Often more economical when technically suitable |
| Selection | Use verified corrosion data | Use verified corrosion data |
Typical applications
| Industry | Typical fitting duty | Why this material is considered |
|---|---|---|
| Chemical processing | Diameter transition in vertical or centerline-aligned process piping | Aggressive acid and mixed-chemical systems |
| Pollution control | Equipment and header connection between different pipe sizes | Flue-gas desulfurization and scrubber piping |
| Waste treatment | Welded size reduction where a compact transition is required | Corrosive effluent and recovery systems |
Application examples are selection context, not a design approval. Confirm process chemistry, pressure, temperature, weld procedure and governing code.
Manufacturing, inspection and documentation
Reducer manufacture requires control of end diameters, overall length, wall transition, ovality, concentricity and bevel geometry. N10276 supply should control heat treatment, contamination, surface condition, PMI and the ordered construction-class/NDE requirements.
Heat-number traceability and PMI when specified.
Large/small-end OD, wall, length, concentricity, ovality and bevel checked.
PT, MT where applicable, UT, RT or third-party witnessing to the ordered scope.
MTC, heat-treatment and inspection records compiled to project requirements.
RFQ checklist
- Complete material grade and UNS where applicable
- ASME B16.9 edition or approved project drawing
- Run, outlet and branch sizes
- Schedule or exact wall thickness at every end
- Seamless or welded construction/class
- Bevel detail and matching pipe dimensions
- Quantity, destination and required delivery date
- EN 10204 3.1, PMI, dimensional and NDE requirements
Frequently asked questions
What is a Hastelloy C276 concentric reducer?
It is a Concentric butt-weld reducer manufactured from ASTM B366/B366M, UNS N10276 nickel-molybdenum-chromium alloy. Its large and small ends share one centerline, producing a symmetrical transition. The ordered material specification controls chemistry, mechanical properties, heat treatment and testing.
Which standard applies to this fitting?
ASME B16.9 covers standard factory-made wrought butt-weld reducer dimensions, tolerances, marking and related requirements. The material basis is ASTM B366/B366M, UNS N10276 nickel-molybdenum-chromium alloy. The purchase order must state the required edition, construction, size, wall and supplementary examinations.
Where is Hastelloy C276 typically selected?
UNS N10276 is considered for chemical reactors and transfer lines, acid systems, chlorination-related equipment, waste treatment and flue-gas desulfurization. Material suitability still depends on fluid chemistry, pressure, temperature, fabrication, corrosion allowance and the governing piping code.
Can heavy-wall and welded construction be supplied?
Yes, subject to manufacturing review. Provide the exact outside diameter, wall thickness or schedule, construction class, end preparation, quantity and NDE requirements so feasibility can be confirmed.
What should an RFQ include?
State the complete material grade, dimensional standard or approved drawing, run and branch sizes, schedule or exact wall, seamless or welded construction, bevel detail, quantity, destination, certification and inspection scope.
Product image is representative. Surface appearance varies by alloy, manufacturing route and finish.
Request a technical quotation
Send the material, size combination, wall, quantity, drawing or standard, and inspection requirements for review.
