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Low-Pressure Brass and Bronze Threaded Pipe Flanges


- For Use With: Air, Drinking Water, Natural Gas, Oil, Steam, Water
- Pressure Class: 150
- Specifications Met:
NPT: ASME B1.20.1, ASME B16.24, ASTM B584, NSF/ANSI 61
BSPT: ASTM B584, BS21 - Pipe Nipples and Pipe: Use Schedule 40 brass
- Fittings:
NPT: Use Class 125 brass
BSPT: Use Class 125 bronze
Also known as Pressure Class 150 flanges, these are designed for low-pressure applications. Bolt two same-size flanges together with a gasket (sold separately) to create an access point within a line. Flanges have good corrosion resistance. To adhere to safety standards for drinking water systems, use flanges that meet NSF/ANSI 61.
For technical drawings and 3-D models, click on a part number.
Bolt Hole | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Pipe Size | Flange OD | For Bolt Dia. | Dia. | No. of | Bolt Circle Dia. | Max. Pressure | Max. Steam Pressure | Material | Each | |
NPT | ||||||||||
1/2 | 3 1/2" | 1/2" | 5/8" | 4 | 2 3/8" | 225 psi @ 72° F | __ | Brass | 00000000 | 000000 |
3/4 | 3 7/8" | 1/2" | 5/8" | 4 | 2 3/4" | 225 psi @ 72° F | __ | Brass | 00000000 | 00000 |
1 | 4 1/4" | 1/2" | 5/8" | 4 | 3 1/8" | 225 psi @ 72° F | __ | Brass | 00000000 | 00000 |
1 1/4 | 4 5/8" | 1/2" | 5/8" | 4 | 3 1/2" | 225 psi @ 72° F | __ | Brass | 00000000 | 000000 |
1 1/2 | 5" | 1/2" | 5/8" | 4 | 3 7/8" | 225 psi @ 72° F | __ | Brass | 00000000 | 000000 |
2 | 6" | 5/8" | 3/4" | 4 | 4 3/4" | 225 psi @ 72° F | __ | Brass | 00000000 | 000000 |
2 1/2 | 7" | 5/8" | 3/4" | 4 | 5 1/2" | 225 psi @ 72° F | __ | Brass | 00000000 | 000000 |
3 | 7 1/2" | 5/8" | 3/4" | 4 | 6" | 225 psi @ 72° F | __ | Brass | 00000000 | 000000 |
4 | 9" | 5/8" | 3/4" | 8 | 7 1/2" | 225 psi @ 72° F | __ | Brass | 00000000 | 000000 |
BSPT | ||||||||||
1/2 | 3 1/2" | 1/2" | 5/8" | 4 | 2 3/8" | 200 psi @ 72° F | 125 psi @ 400° F | Bronze | 00000000 | 00000 |
3/4 | 3 7/8" | 1/2" | 5/8" | 4 | 2 3/4" | 200 psi @ 72° F | 125 psi @ 400° F | Bronze | 00000000 | 000000 |
1 | 4 1/4" | 1/2" | 5/8" | 4 | 3 1/8" | 200 psi @ 72° F | 125 psi @ 400° F | Bronze | 00000000 | 000000 |
1 1/2 | 5" | 1/2" | 5/8" | 4 | 3 7/8" | 200 psi @ 72° F | 125 psi @ 400° F | Bronze | 00000000 | 000000 |
2 | 6" | 5/8" | 3/4" | 4 | 4 3/4" | 200 psi @ 72° F | 125 psi @ 400° F | Bronze | 00000000 | 000000 |
Brass and Bronze Unthreaded Pipe Flanges
Bolt these flanges to equipment or to another same-size, flat-surface flange with a gasket (sold separately). They have good corrosion resistance.
Socket-connect flanges braze onto unthreaded pipe with a brazing ring (sold separately) for a strong, leak-resistant connection. They are also known as Silbraze flanges.
Cap flanges are also known as blind flanges.
For technical drawings and 3-D models, click on a part number.


- For Use With: Air, Natural Gas, Oil, Water, Steam
- Specifications Met: MIL-F-1183
- Pipe Nipples and Pipe: Use Schedule 40 brass
Flanges | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Bolt Hole | Brazing Rings | |||||||||||
Pipe Size | Flange OD | For Bolt Dia. | Dia. | No. of | Bolt Circle Dia. | Max. Pressure | Max. Steam Pressure | Material | Each | Each | ||
1/2 | 3 1/2" | 1/2" | 5/8" | 4 | 2 3/8" | 200 psi @ 72° F | 200 psi @ 425° F | Bronze | 0000000 | 0000000 | 0000000 | 00000 |
3/4 | 3 7/8" | 1/2" | 5/8" | 4 | 2 3/4" | 200 psi @ 72° F | 200 psi @ 425° F | Bronze | 0000000 | 000000 | 0000000 | 0000 |
1 | 4 1/4" | 1/2" | 5/8" | 4 | 3 1/8" | 200 psi @ 72° F | 200 psi @ 425° F | Bronze | 0000000 | 000000 | 0000000 | 0000 |
1 1/2 | 5" | 1/2" | 5/8" | 4 | 3 7/8" | 200 psi @ 72° F | 200 psi @ 425° F | Bronze | 0000000 | 000000 | 0000000 | 0000 |
2 | 6" | 5/8" | 3/4" | 4 | 4 3/4" | 200 psi @ 72° F | 200 psi @ 425° F | Bronze | 0000000 | 000000 | 0000000 | 0000 |


- For Use With: Air, Argon, Natural Gas, Nitrogen Gas, Oil, Oxygen, Water
- Pressure Class : 150
- Specifications Met: ASME B16.24
- Pipe Nipples and Pipe: Use Schedule 40 brass