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Hexagonal malleable iron reducing coupling, dark finish, 1 inch to half inch FNPT threads

Value Brand

Value Brand Reducing Coupling 1" x 1/2" FNPT Malleable Iron Class 150

SKU CH-SRRD-SZ3B7

Connects a 1 in female NPT pipe to a 1/2 in female NPT pipe using malleable iron rated for Class 150 service

  • Reduces 1" pipe to 1/2" FNPT for flexible plumbing connections
  • Malleable iron construction provides durable strength for Class 150 pressure systems
  • Female NPT threads on both ends ensure secure, leak-resistant joints
  • 11-1/2 and 14 threads per inch match standard NPT specifications
  • Zoro Select brand delivers reliable fitting performance for professional installations

What this fitting does

This reducing coupling joins a 1 inch female NPT pipe to a 1/2 inch female NPT pipe in water, gas or air lines. It is rated Class 150 for standard pressure service and suits residential, commercial or light industrial plumbing jobs where a straight size transition is required.

Malleable iron construction and thread detail

The body is cast from malleable iron for mechanical strength and resistance to cracking under vibration or thermal cycling. Both ends use tapered NPT threads, 11 1/2 threads per inch on the large side and 14 threads per inch on the small side, so the joint seals with thread sealant or tape without a separate gasket.

Pressure rating and installation practice

Class 150 rating covers typical low-pressure hot and cold water, compressed air and inert gas systems at ambient temperatures. The iron material conducts heat away from the joint, reducing local stress during temperature swings, and the tapered threads self-tighten under pressure to maintain a leak-free seal when assembled with proper thread compound.

Highlights

  • Reduces 1" pipe to 1/2" FNPT for flexible plumbing connections
  • Malleable iron construction provides durable strength for Class 150 pressure systems
  • Female NPT threads on both ends ensure secure, leak-resistant joints
  • 11-1/2 and 14 threads per inch match standard NPT specifications
  • Zoro Select brand delivers reliable fitting performance for professional installations

Specifications

BrandZORO SELECT

Questions about this item

What does the Class 150 rating mean for the pressure this coupling can handle?

The Class 150 designation indicates the fitting is rated for 150 psi working pressure in standard malleable iron service.

What thread counts do the 1 inch and 1/2 inch female NPT ends use?

The 1 inch end uses 11 1/2 threads per inch and the 1/2 inch end uses 14 threads per inch, both to NPT standard.

How do I seal the NPT threads correctly and what is the common mistake?

Apply PTFE tape or pipe dope on the male threads only, then tighten two turns past hand-tight; the common mistake is over-tightening which can crack the malleable iron.

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