
Mueller Streamline 521-709 2-1/2" Black Iron Union
- Item #
- BLIF-250-UNI
- Mfr. part #
- 521-709
- UPC
- 032888360594
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- TypeUnion
- Size2-1/2"
- ConnectionFIP
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Shipping details
- Shipping weight: 4.7 lb
| Brand | Mueller Streamline |
| Manufacturer part # | 521-709 |
| Connection Type | FIP |
| Size | 2-1/2" |
| Type | Union |
| UPC | 032888360594 |
Mueller Streamline 521-709 is a 2-1/2" union in black malleable iron, FPT (FPT = female pipe thread).
A union can be taken apart without cutting the line, so equipment such as a pump, water heater or valve can be removed for service.
Class 150 black malleable iron fittings are the standard threaded fitting for natural gas and propane lines, steam, compressed air and fire sprinkler work. Material is to ASTM A197 and dimensions to ASME B16.3, with tapered NPT threads, so they make up with Schedule 40 black pipe and nipples. Black iron is not used on potable water.
Specifications
- Brand: Mueller Streamline
- Manufacturer Part #: 521-709
- Size: 2-1/2"
- Type: Union
- Connections: FPT
- Material: Black malleable iron, Class 150
- Standards: ASTM A197 material, ASME B16.3 dimensions, ASME B1.20.1 NPT threads
- Pressure rating: 300 psi water, oil and gas (non-shock); 150 psi saturated steam
- UPC: 032888360594
- Category: Black Iron Fittings
See also: all black iron fittings, thread sealant, black iron nipples, all Mueller Streamline.
Questions about fit or compatibility? Ask our team. We usually reply within one business day.
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