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Galvanised malleable iron reducing coupling, 4 inch to 3 inch NPT threads

Value Brand

Value Brand Reducing Coupling Malleable Iron Galvanized Class 150 4 in NPT 3 in NPT

SKU CH-QJSG-3B7FW

Connects 4 in NPT to 3 in NPT pipe with galvanized malleable iron rated for Class 150 service

  • Reduces pipe size from 4 in to 3 in NPT
  • Malleable iron construction provides mechanical strength
  • Galvanized coating resists corrosion in plumbing systems
  • Class 150 rating suits standard pressure applications
  • Female NPT threads on both ends ensure compatible connections

Reducing Coupling 4 in NPT to 3 in NPT

This galvanised malleable-iron reducing coupling connects a 4 in NPT female thread to a 3 in NPT female thread. It is rated Class 150 for standard-pressure piping systems. The fitting is supplied new and meets the dimensions for straight-threaded pipe connections.

Suitable for plumbing and industrial pipe reductions

Installers joining dissimilar NPT pipe sizes in water, air or inert-gas lines will find this coupling appropriate. It is not intended for systems that require a higher pressure class, different thread standards or non-galvanised materials.

Check thread compatibility and pressure rating

Verify that both pipe ends are cut to NPT standard and that the system design pressure does not exceed the Class 150 rating. Confirm the galvanised finish is compatible with the intended fluid and local code requirements before installation.

Highlights

  • Reduces pipe size from 4 in to 3 in NPT
  • Malleable iron construction provides mechanical strength
  • Galvanized coating resists corrosion in plumbing systems
  • Class 150 rating suits standard pressure applications
  • Female NPT threads on both ends ensure compatible connections

Specifications

BrandZORO SELECT

Questions about this item

What pipe sizes must I already have to connect this 4 in NPT to 3 in NPT reducing coupling?

You need one pipe with a 4 in NPT male thread and another with a 3 in NPT male thread; the coupling provides female threads on both ends to join them.

Will this Class 150 galvanized malleable iron coupling mate with older black iron or brass fittings I am keeping in the same line?

Yes, the NPT threads are standard taper threads, so it will thread onto any matching NPT male fitting regardless of material, provided the pressure rating suits your system.

How can I verify the joint is sealing properly after I assemble the coupling?

Pressurise the line to its working pressure and inspect both threaded joints for leaks; a properly tightened NPT joint with sealant should show no weeping at the rated Class 150 pressure.

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