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Straight copper union with cup ends, matte metallic finish

Nibco, Inc.

Nibco, Inc. 733 Copper Union 2 1/2 in Cup 336 psi

SKU CH-0JKH-A70Q6

A straight copper union joins two 2 1/2 in tubes and handles 336 psi at 100 °F

  • Sweat copper union joins 2-1/2 in tubes securely
  • Rated 336 psi at 100 °F for reliable pressure handling
  • Withstands 400 °F maximum temperature in hot-line service
  • Cast copper body resists corrosion in air and non-potable water
  • Straight union design allows quick disassembly for maintenance

2-1/2-inch Copper Union

The NIBCO 733 is a straight sweat union for 2-1/2-inch copper tube. It joins two 2-5/8-inch outer-diameter lines in air or non-potable water systems. The cast copper body is rated to 336 psi at 100 degrees F and 400 degrees F maximum temperature.

Replacing Flanged or Threaded Joints

This union replaces flanged or threaded connections where a compact, soldered joint is preferred. The jump is worth it when the system operates up to 336 psi and 400 degrees F and the installer wants a leak-free copper-to-copper seal without gaskets.

Sweat Installation Notes

The cup ends are soldered directly to 2-1/2-inch copper tube using standard sweat technique. Clean both tube ends and fitting cups thoroughly, apply flux, heat evenly and feed solder until the joint is full. The most common error is insufficient heat on the larger mass, which leaves voids and causes leaks at pressure.

Highlights

  • Sweat copper union joins 2-1/2 in tubes securely
  • Rated 336 psi at 100 °F for reliable pressure handling
  • Withstands 400 °F maximum temperature in hot-line service
  • Cast copper body resists corrosion in air and non-potable water
  • Straight union design allows quick disassembly for maintenance

Specifications

BrandNibco

Questions about this item

What copper tube size and outer diameter does the Nibco 733 union accept for sweat fitting?

It fits 2 1/2 inch copper tube size with a 2 5/8 inch outer diameter on both cup ends.

How is this straight union installed and what common step causes leaks?

Sweat solder both cup ends to the copper tubing; the step often missed is cleaning and fluxing each joint thoroughly before heating.

What pressure and temperature limits determine when this union must be replaced?

Rated for 336 psi at 100°F and up to 400°F; replace if system pressure or temperature exceeds these limits.

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