ASTM A333 Gr 6 Reducing FlangeASTM A350 · ASME B16.5 · Manufacturer, stockist & exporter, India
SA-333 Gr 6 · Low-temperature carbon steel pipe · RF
An ASTM A333 Gr 6 reducing flange is a flange with a smaller bore than its outside dimensions, connecting to a smaller pipe, for use with ASTM A333 Gr 6 pipe. ASTM A333 Gr 6 itself is a pipe or plate specification, so the matching reducing flange is made to ASTM A350 LF2 — which is what we supply for A333 Gr 6 lines. A reducing flange changes pipe size at a flanged joint without a separate reducer, saving space and a weld. Use it where the flow disturbance from a sudden change is acceptable.
- ASTM A350
- ASME B16.5
- EN 10204 3.1 / 3.2
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is an ASTM A333 Gr 6 Reducing Flange?
- What it is
- A flange with a smaller bore than its outside dimensions, connecting to a smaller pipe
- Material
- ASTM A350 LF2
- Dimensions
- ASME B16.5
- Grade
- ASTM A333 Gr 6
- Best at
- Cold-climate and refrigerated piping down to −45 °C
ASTM A333 Gr 6 Reducing Flange Specification
| Product | ASTM A333 Gr 6 Reducing Flange |
|---|---|
| Material standard | ASTM A350 LF2 |
| Dimensional standard | ASME B16.5 |
| Sizes | ½" – 24" (ASME B16.5) · 26" – 60" (ASME B16.47) |
| Pressure class | Class 150, 300, 400, 600, 900, 1500, 2500 · PN 6 – PN 100 |
| Facing | RF · FF · RTJ · tongue & groove |
| Bore | To match pipe schedule (state on order) |
| Testing | Chemical & mechanical per heat · NDT · impact where specified |
| Documents | EN 10204 3.1 · 3.2 with third-party inspection |
When to Choose a Reducing Flange
A reducing flange changes pipe size at a flanged joint without a separate reducer, saving space and a weld. Use it where the flow disturbance from a sudden change is acceptable.
- Outside dimensions of the larger size
- Bore / hub for the smaller pipe
- Weld neck, slip-on or threaded styles
ASTM A333 Gr 6 Reducing Flange Chemical Composition
| Element | Weight % |
|---|---|
| Carbon | 0.30 max |
| Manganese | 0.29 – 1.06 |
| Silicon | 0.10 min |
| Phosphorus | 0.025 max |
| Sulphur | 0.025 max |
ASTM A333 Gr 6 Reducing Flange Mechanical Properties
| Minimum values | Value |
|---|---|
| Tensile strength | 415 MPa · 60 ksi |
| Yield strength 0.2% | 240 MPa · 35 ksi |
| Elongation | 30% |
| Charpy impact | Tested at −45 °C |
Full chemistry, properties and equivalents are on the ASTM A333 Gr 6 grade page.
Other ASTM A333 Gr 6 flanges
ASTM A333 Gr 6 Reducing Flanges for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiASTM A333 Gr 6 Reducing Flange dimensions — ASME B16.5 Class 150 & 300
Outside diameter, thickness and bolting are set by size and class. Values in mm; thickness excludes the 1.6 mm raised face.
| NPS | Cl 150 OD | Cl 150 thickness | Cl 150 bolt circle | Cl 150 bolts | Cl 300 OD | Cl 300 thickness | Cl 300 bolt circle | Cl 300 bolts |
|---|---|---|---|---|---|---|---|---|
| ½" | 90 | 9.6 | 60.3 | 4 × ½" | 95 | 12.7 | 66.7 | 4 × ½" |
| 1" | 110 | 12.7 | 79.4 | 4 × ½" | 125 | 15.9 | 88.9 | 4 × ⅝" |
| 1½" | 125 | 15.9 | 98.4 | 4 × ½" | 155 | 19.1 | 114.3 | 4 × ¾" |
| 2" | 150 | 17.5 | 120.7 | 4 × ⅝" | 165 | 20.7 | 127.0 | 8 × ⅝" |
| 3" | 190 | 22.3 | 152.4 | 4 × ⅝" | 210 | 27.0 | 168.3 | 8 × ¾" |
| 4" | 230 | 22.3 | 190.5 | 8 × ⅝" | 255 | 30.2 | 200.0 | 8 × ¾" |
| 6" | 280 | 23.9 | 241.3 | 8 × ¾" | 320 | 35.0 | 269.9 | 12 × ¾" |
| 8" | 345 | 27.0 | 298.5 | 8 × ¾" | 380 | 39.7 | 330.2 | 12 × ⅞" |
| 10" | 405 | 28.6 | 362.0 | 12 × ⅞" | 445 | 46.1 | 387.4 | 16 × 1" |
| 12" | 485 | 30.2 | 431.8 | 12 × ⅞" | 520 | 49.3 | 450.8 | 16 × 1⅛" |
Full chart: ASME B16.5 flange dimensions.
ASTM A333 Gr 6 Reducing Flange — questions buyers ask
Is a reducing flange better than a reducer plus flange?
It saves length and a weld, but a buttweld reducer gives smoother flow. Choose by space and process needs.
Which standard covers ASTM A333 Gr 6 reducing flanges?
The material is ASTM A350 LF2; dimensions follow ASME B16.5. Always state both on your purchase order, with the edition if your project specifies one.
What decides the price of a ASTM A333 Gr 6 reducing flange?
The steel price, the size and pressure 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