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Galvanized steel square head pipe plug, 3-1/2 inch MNPT threads

Anvil

Anvil 3-1/2" MNPT Galvanized Square Head Plug 319902680

SKU CH-FDGZ-8C1HS

Galvanised steel square-head plug with 3-1/2" MNPT threads for Schedule 40 and 80 pipe, rated to 300 psi at 150 °F and 150 psi steam at 350 °F

  • Galvanized steel resists corrosion in plumbing systems
  • Square head allows easy installation with a wrench
  • Rated 300 psi at 150 °F for water service
  • Withstands 150 psi steam pressure at 350 °F
  • Meets A197 standard for Schedule 40 and 80 pipe

Anvil 3-1/2" MNPT Square Head Plug

This Anvil plug provides a solid threaded closure for 3-1/2 inch nominal pipe size systems. It is manufactured from galvanized steel to A197 specification for corrosion resistance. The fitting suits Schedule 40 and Schedule 80 pipe dimensions. It is intended for plumbing and industrial piping installations requiring a permanent or removable seal.

Suited for threaded steel pipe networks up to 300

Installers working with water, oil, or air lines at 150 degrees Fahrenheit will find the pressure rating appropriate. The square drive allows installation with a standard wrench where a hex head would not fit. Systems requiring steam service above 150 psi at 350 degrees Fahrenheit should select a higher-rated fitting. Buyers needing a pre-applied thread sealant or an integrated gasket seal must source those separately.

Fits Schedule 40 and 80 threaded pipe ends

The plug threads directly into a female NPT fitting without additional adapters. Galvanized coating protects the steel in damp or outdoor environments. The solid construction leaves no internal cavity to trap debris. No sealant is included, so installers must supply pipe dope or tape compatible with the 350 degree Fahrenheit upper temperature limit.

Highlights

  • Galvanized steel resists corrosion in plumbing systems
  • Square head allows easy installation with a wrench
  • Rated 300 psi at 150 °F for water service
  • Withstands 150 psi steam pressure at 350 °F
  • Meets A197 standard for Schedule 40 and 80 pipe

Specifications

BrandANVIL

Questions about this item

What size pipe thread does the 3-1/2" MNPT plug fit?

The plug uses a 3-1/2 inch MNPT thread that matches Schedule 40 and Schedule 80 pipe.

Will the galvanized square head plug handle the same pressure and temperature as my existing Schedule 80 steel pipe?

Yes, it is rated 300 psi at 150 °F and 150 psi at 350 °F, matching typical Schedule 80 limits.

How can I confirm the plug is sealing properly after I install it?

Pressurise the system to its working pressure and check the joint for leaks; the solid A197 steel plug has no sealant or gasket to mask a fault.

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