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Bronze straight union with cup and FNPT ends

Nibco, Inc.

Nibco, Inc. 7333LF 3/8 in Bronze Union Cup FNPT

SKU CH-RNA9-9D0FA

Connects 3/8 in copper tube to 3/8 in FNPT for potable water systems at up to 623 psi and 200 Degrees F

  • Lead-free bronze meets NSF/ANSI 61 Annex G for potable water
  • Rated 623 psi at 200 °F for reliable pressure handling
  • Sweat cup to FNPT straight union simplifies copper-to-thread transitions
  • Cast to ASTM B584 C87850 for consistent alloy quality
  • Conforms to ASME B 16.18 dimensional standards

Bronze Union Cup for Potable Water

The NIBCO 7333LF is a straight union fitting made from C87850 bronze. It connects a 3/8 inch copper tube on the cup side to a 3/8 inch FNPT thread on the other. The fitting meets ASME B 16.18, ASTM B584 and NSF/ANSI 61 Annex G standards for potable water systems. It is rated for a maximum operating pressure of 623 psi and a maximum temperature of 200 Degrees F.

For Copper Tube to Threaded Pipe Transitions

This union suits installers joining 3/8 inch copper tubing to a female threaded pipe connection in potable water lines. It is not for use with larger tube sizes, different thread types or press-fit connection methods. Systems requiring a different pressure class or a non-bronze material should use an alternative fitting.

623 psi Maximum Operating Pressure

The 623 psi pressure rating is the primary specification that determines suitability for the intended installation. Verify that the system design pressure does not exceed this limit. The 200 Degrees F temperature ceiling and the NSF/ANSI 61 Annex G certification for potable water are the other critical compliance factors.

Highlights

  • Lead-free bronze meets NSF/ANSI 61 Annex G for potable water
  • Rated 623 psi at 200 °F for reliable pressure handling
  • Sweat cup to FNPT straight union simplifies copper-to-thread transitions
  • Cast to ASTM B584 C87850 for consistent alloy quality
  • Conforms to ASME B 16.18 dimensional standards

Specifications

BrandNIBCO

Questions about this item

How much pressure can the 3/8 in bronze union cup handle before it becomes the limiting factor under sustained use?

The fitting is rated for a maximum operating pressure of 623 psi, which is the limit that will be reached first during continuous service.

Will the bronze union cup generate noticeable heat or noise when installed in a line running all day?

As a passive bronze fitting with no moving parts, it produces no noise and adds negligible heat beyond the fluid temperature, which can reach up to 200 degrees F.

What pipe and tube sizes must already be in place for this 3/8 in FNPT union to connect properly?

You need a 3/8 in female NPT threaded pipe on one side and 3/8 in copper tubing with a 1/2 in outer diameter for the sweat cup connection on the other.

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