SS 310 / 310S ReducerASTM A403 · ASME B16.9 · Manufacturer, stockist & exporter, India
AISI 310S · UNS S31008
An SS 310 / 310S reducer is a fitting that joins two pipes of different sizes, made from SS 310 / 310S to ASTM A403 WP310S. Concentric reducers keep the centreline in line and suit vertical lines. Eccentric reducers keep one side flat — flat on top at pump suctions to avoid air pockets, flat on the bottom in pipe racks.
- ASTM A403
- ASME B16.9
- EN 10204 3.1 / 3.2
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is an SS 310 / 310S Reducer?
- What it is
- A fitting that joins two pipes of different sizes
- Material
- ASTM A403 WP310S
- Dimensions
- ASME B16.9 · MSS SP-43
- Grade
- SS 310 / 310S · UNS S31008
- Best at
- Furnaces, burners and heat treatment at high temperature
SS 310 / 310S Reducer Specification
| Product | SS 310 / 310S Reducer |
|---|---|
| Material standard | ASTM A403 WP310S |
| Dimensional standard | ASME B16.9 · MSS SP-43 |
| Sizes | ½" – 48" |
| Wall / class | Sch 5S – XXS, to match pipe |
| Ends | Bevelled to ASME B16.25 |
| Testing | PMI · dimensional · NDT and IGC on request |
| Documents | EN 10204 3.1 · 3.2 with third-party inspection |
When to Choose a Reducer
Concentric reducers keep the centreline in line and suit vertical lines. Eccentric reducers keep one side flat — flat on top at pump suctions to avoid air pockets, flat on the bottom in pipe racks.
- Concentric and eccentric
- Flat-top on pump suction
- Seamless or welded
SS 310 / 310S Reducer Chemical Composition
| Element | Weight % |
|---|---|
| Chromium | 24.0 – 26.0 |
| Nickel | 19.0 – 22.0 |
| Carbon | 0.08 max |
| Manganese | 2.00 max |
| Silicon | 1.50 max |
| Phosphorus | 0.045 max |
| Sulphur | 0.030 max |
| Iron | Balance |
SS 310 / 310S Reducer Mechanical Properties
| Annealed plate & sheet | Value |
|---|---|
| Tensile strength | 515 MPa · 75 ksi |
| Yield strength 0.2% | 205 MPa · 30 ksi |
| Elongation | 40% |
| Hardness | 217 HB max |
Full chemistry, properties and equivalents are on the SS 310 / 310S grade page.
Other SS 310 / 310S pipe fittings
SS 310 / 310S Reducers for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiSS 310 / 310S Reducer dimensions — ASME B16.9
Values in mm, the same for every material; the wall thickness matches the pipe schedule.
| NPS | OD | Reducer length H |
|---|---|---|
| ½" | 21.3 | — |
| ¾" | 26.7 | 38 |
| 1" | 33.4 | 51 |
| 1½" | 48.3 | 64 |
| 2" | 60.3 | 76 |
| 3" | 88.9 | 89 |
| 4" | 114.3 | 102 |
| 6" | 168.3 | 140 |
| 8" | 219.1 | 152 |
| 10" | 273.1 | 178 |
| 12" | 323.9 | 203 |
| 16" | 406.4 | 356 |
| 20" | 508.0 | 508 |
| 24" | 610.0 | 508 |
Full chart: ASME B16.9 fitting dimensions.
SS 310 / 310S Reducer — questions buyers ask
Why use an eccentric reducer at a pump suction?
Installed flat side up, it prevents air pockets that can cause cavitation.
Which standard covers SS 310 / 310S reducers?
The material is ASTM A403 WP310S; dimensions follow ASME B16.9 · MSS SP-43. Always state both on your purchase order, with the edition if your project specifies one.
What decides the price of a SS 310 / 310S reducer?
The alloy price, the size and schedule or class, quantity, and the testing and documents required. Send your list and we quote the same working day.
What documents do you supply?
EN 10204 3.1 mill certificates as standard, 3.2 with third-party inspection on request, plus dimensional and PMI reports.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026