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Straight copper adapter with sweat and threaded ends

Nibco, Inc.

Nibco, Inc. 604 3" C x 3" MNPT Copper Adapter

SKU CH-E288-QT97X MPN 604

A straight copper adapter joining 3-inch sweat tubing to 3-inch MNPT threads for air, gas or potable water systems

  • TypeDrain Components
  • MaterialHAWA
  • Wrot copper construction resists corrosion in potable water systems
  • Sweat-to-MNPT design joins 3 in copper tube to 3 in male pipe threads
  • Rated 317 psi at 100 Degrees F for high-pressure air, gas or water lines
  • Withstands 400 Degrees F continuous operating temperature
  • Straight adapter shape simplifies in-line installation without offsets

Copper Sweat Adapter for 3" Lines

This Nibco 604 straight adapter joins a 3-inch copper tube to a 3-inch male NPT thread using a sweat fitting. It is built from wrought copper and rated for air, gases and potable water systems. Plumbers and mechanical contractors use it when transitioning from copper piping to threaded iron or steel components.

Replaces Direct Threaded Copper Joints

The adapter removes the need to thread copper tube directly, which can weaken the wall and create leak paths. The jump is worth it when a secure, soldered cup connection on the copper side and a standard MNPT connection on the other side simplify assembly and future maintenance.

Sustained Pressure and Temperature Performance

The fitting withstands a maximum operating pressure of 317 psi at 100 degrees F and a maximum operating temperature of 400 degrees F. These ratings apply to continuous service conditions rather than short test bursts, so the joint remains reliable in hot-water circulation and compressed-air lines.

Highlights

  • Wrot copper construction resists corrosion in potable water systems
  • Sweat-to-MNPT design joins 3 in copper tube to 3 in male pipe threads
  • Rated 317 psi at 100 Degrees F for high-pressure air, gas or water lines
  • Withstands 400 Degrees F continuous operating temperature
  • Straight adapter shape simplifies in-line installation without offsets

Specifications

TypeDrain Components
MaterialHAWA
BrandNibco
Model604 3

Questions about this item

What copper tube size and male thread size does the 3" adapter connect?

The adapter joins a 3 in copper tube on the sweat side to a 3 in MNPT thread on the other side.

How is the sweat end of this straight adapter installed, and what step is often missed?

Clean the tube and fitting, apply flux, slide the cup onto the tube, then heat evenly and feed solder until the joint is full; skipping thorough cleaning causes leaks.

When should the adapter be inspected or replaced in a potable water system?

Inspect joints annually for corrosion or drips; replace the fitting if green patina appears or if pressure tests exceed 317 psi at 100 Degrees F.

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