ASTM A333 Gr 6 Threaded FlangeASTM A350 · ASME B16.5 · Manufacturer, stockist & exporter, India
SA-333 Gr 6 · Low-temperature carbon steel pipe · THD
An ASTM A333 Gr 6 threaded flange is a flange with a tapered internal thread that screws onto threaded pipe, for use with ASTM A333 Gr 6 pipe. ASTM A333 Gr 6 itself is a pipe or plate specification, so the matching threaded flange is made to ASTM A350 LF2 — which is what we supply for A333 Gr 6 lines. Use a threaded flange where welding is not allowed — for example in explosive areas — on small-bore, low-pressure lines. Threads are NPT to ASME B1.20.1.
- 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 Threaded Flange?
- What it is
- A flange with a tapered internal thread that screws onto threaded pipe
- Material
- ASTM A350 LF2
- Dimensions
- ASME B16.5 · ASME B1.20.1
- Grade
- ASTM A333 Gr 6
- Best at
- Cold-climate and refrigerated piping down to −45 °C
ASTM A333 Gr 6 Threaded Flange Specification
| Product | ASTM A333 Gr 6 Threaded Flange |
|---|---|
| Material standard | ASTM A350 LF2 |
| Dimensional standard | ASME B16.5 · ASME B1.20.1 |
| 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 Threaded Flange
Use a threaded flange where welding is not allowed — for example in explosive areas — on small-bore, low-pressure lines. Threads are NPT to ASME B1.20.1.
- NPT threads to ASME B1.20.1
- Not for cyclic or high-temperature service
- Seal-welding is sometimes added after make-up
ASTM A333 Gr 6 Threaded 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 Threaded 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 Threaded Flanges for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiASTM A333 Gr 6 Threaded 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 Threaded Flange — questions buyers ask
Can threaded flanges be used in high-pressure service?
They are rated like other flanges in their class, but threaded joints are not recommended for cyclic, high-temperature or highly corrosive service.
Which standard covers ASTM A333 Gr 6 threaded flanges?
The material is ASTM A350 LF2; dimensions follow ASME B16.5 · ASME B1.20.1. 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 threaded 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