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Malleable iron reducing coupling with female NPT threads, black finish

Value Brand

Value Brand Reducer Coupling 4" x 1" FNPT Malleable Iron Class 150

SKU CH-WAS6-R5ZTZ

Malleable iron reducing coupling joins 4-inch and 1-inch FNPT pipes at Class 150

  • Connects 4-inch and 1-inch NPT pipes securely
  • Malleable iron body withstands Class 150 pressure ratings
  • Female NPT threads on both ends for leak-free joints
  • Zoro Select brand ensures consistent manufacturing quality
  • Ready for immediate installation in plumbing systems

4 in x 1 in Reducing Coupling

This malleable iron reducing coupling connects a four inch female NPT pipe to a one inch female NPT pipe in Class 150 service. It suits installers joining dissimilar pipe sizes in water, oil or gas lines where threaded joints are required. The fitting is new and ready for immediate installation.

Malleable Iron Class 150 Construction

The malleable iron body provides mechanical strength for pressures up to Class 150 rating while resisting cracking under vibration or thermal cycling. Both ends use tapered NPT threads so sealant or tape creates a pressure tight joint without welding or flanges. The 11 1/2 thread pitch on the smaller end matches standard NPT tooling.

Verify Pipe Sizes and Thread Type Before Ordering

Confirm the existing system uses NPT threads and that the four inch and one inch nominal sizes match the pipes being joined. This coupling will not fit BSPT, metric or compression style connections. Check that the working pressure and temperature of the installation fall within the Class 150 limits for malleable iron.

Highlights

  • Connects 4-inch and 1-inch NPT pipes securely
  • Malleable iron body withstands Class 150 pressure ratings
  • Female NPT threads on both ends for leak-free joints
  • Zoro Select brand ensures consistent manufacturing quality
  • Ready for immediate installation in plumbing systems

Specifications

BrandZORO SELECT

Questions about this item

What thread standard does the 4" x 1" reducer coupling use?

Both ends are female NPT threads, 8 threads per inch on the 4" side and 11 1/2 threads per inch on the 1" side.

What clearance is needed to fit this malleable iron coupling?

The Class 150 malleable iron body requires enough pipe run to accommodate the full thread engagement on both the 4" and 1" female ends.

How is this reducing coupling installed, and what step is often missed?

Apply pipe thread sealant to the male pipe threads, then tighten each pipe into the female NPT ends; the step often missed is using the correct sealant for the fluid type.

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