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Anvil hex locknut, 2-1/2 inch FNPT, black anodized malleable iron

Anvil

Anvil 318913720 Hex Locknut 2-1/2" Pipe FNPT Malleable Iron

SKU CH-1K84-E6JJM

A 2-1/2 inch Class 150 malleable iron hex locknut with female NPT threads rated from -20 to 350 degrees F for Schedule 40 pipe

  • Hex locknut secures 2-1/2" pipe connections
  • Class 150 rating handles demanding pressure systems
  • Malleable iron construction resists mechanical stress
  • Female NPT threads ensure compatible pipe fit
  • Operates from -20 to 350 degrees Fahrenheit

Anvil 2-1/2" FNPT Hex Locknut

This Anvil hex locknut is a Class 150 malleable iron fitting with female NPT threads. It connects to 2-1/2 inch nominal pipe size for Schedule 40 systems. Plumbers and maintenance technicians use it to secure threaded pipe joints in water, oil or gas lines.

Installation and common issues

The nut threads onto a male NPT pipe end by hand and tightens with a standard wrench on the hex flats. Apply pipe sealant or tape to the male threads before assembly to prevent leaks. Over-tightening can crack the malleable iron body or strip the threads, especially near the 350 degree F upper temperature limit.

Class 150 pressure rating decides fit

The Class 150 rating determines the maximum working pressure for the piping system at ambient temperature. Verify that your system design pressure does not exceed this class rating before selecting this locknut. Buyers needing a higher pressure class or a different nominal pipe size must choose another fitting.

Highlights

  • Hex locknut secures 2-1/2" pipe connections
  • Class 150 rating handles demanding pressure systems
  • Malleable iron construction resists mechanical stress
  • Female NPT threads ensure compatible pipe fit
  • Operates from -20 to 350 degrees Fahrenheit

Specifications

BrandANVIL

Questions about this item

How can I confirm the locknut is sealing correctly after threading it onto the 2-1/2" pipe?

After installation, pressurise the system up to the Class 150 rating and check for leaks at the Female NPT joint; the black anodised malleable iron should show no weeping between -20°F and 350°F.

What comes with the locknut and what must I supply?

The box contains only the single 2-1/2" FNPT hex locknut; you must provide the matching Schedule 40 pipe, thread sealant or tape, and a suitably sized wrench.

Which specification should I match when selecting this locknut for my piping system?

Choose this locknut when your system uses 2-1/2" nominal pipe size, Class 150 pressure rating, Schedule 40 wall thickness, and Female NPT threads.

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