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Hexagonal malleable iron reducer coupling with female threaded ends

Zoro Select

Zoro Select Reducer Coupling 1-1/2" x 1" FNPT Malleable

SKU CH-K08G-5TK5F

Reducer coupling joins 1-1/2 inch and 1 inch FNPT threads in Class 300 malleable iron

  • Malleable iron construction withstands high pressure
  • Class 300 rating suits demanding plumbing systems
  • Female NPT threads on both ends enable secure connections
  • Reduces 1-1/2 inch pipe to 1 inch pipe
  • Straight coupling design simplifies installation layout

Reducer Coupling 1-1/2" x 1" FNPT

The Zoro Select reducer coupling joins a 1-1/2 inch female threaded pipe to a 1 inch female threaded pipe. It is made from malleable iron rated for Class 300 service. Plumbers and maintenance technicians use it to transition between different pipe sizes in water, oil or gas lines. The straight body keeps the flow path direct.

Sustained pressure performance

Malleable iron construction handles continuous operating pressure at the Class 300 rating without deformation. The material resists vibration and thermal cycling better than cast iron in fixed installations. Thread engagement remains secure under long-term mechanical stress. It is not suited for systems that exceed the Class 300 pressure envelope.

FNPT thread limits

Both ends use Female National Pipe Taper threads with an 11 1/2 threads-per-inch pitch. The taper seal requires proper thread sealant or tape to prevent leaks. Mismatched thread standards or damaged threads will compromise the joint. This coupling does not adapt to metric, BSPT or compression fittings.

Highlights

  • Malleable iron construction withstands high pressure
  • Class 300 rating suits demanding plumbing systems
  • Female NPT threads on both ends enable secure connections
  • Reduces 1-1/2 inch pipe to 1 inch pipe
  • Straight coupling design simplifies installation layout

Specifications

BrandZORO SELECT

Questions about this item

How much heat does the 300-class malleable iron coupling generate when fluid runs through it all day?

The Class 300 malleable iron body does not generate heat; it simply conducts the temperature of the fluid passing through it.

What pipe threads must my existing lines have to connect to the 11 1/2 FNPT ends?

Both ends require 11 1/2 threads per inch female NPT, so the mating pipes must be male NPT with the same 11 1/2 TPI pitch.

Will the 1-1/2" to 1" reduction restrict flow when paired with older steel pipe of the same nominal sizes?

The coupling matches standard 1-1/2" and 1" NPT dimensions, so it fits older steel pipe of those sizes without creating an additional restriction beyond the normal reduction.

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