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Anvil malleable iron pipe union, 3/8 inch FNPT, class 150, hex nut visible

Anvil

Anvil 312822042 3/8 in Malleable Iron Union Class 150

SKU CH-BZ6C-3MX1M

A malleable iron pipe union rated for 300 psi at 150 °F with brass seats and FNPT connections

  • Rated for 300 psi working pressure at 150 °F
  • Handles saturated steam up to 150 psi for demanding systems
  • Operates reliably from –20 °F to 350 °F across seasons
  • Brass seat resists corrosion and ensures tight sealing
  • Meets ASME B16.39 with UL and FM approvals

Anvil 312822042 Malleable Iron Union 3/8 in FNPT

This Anvil 312822042 union connects 3/8 inch FNPT piping using malleable iron rated to Class 150. It handles saturated steam at 150 psi and water pressure up to 300 psi at 150 degrees F. The operating temperature spans from -20 to 350 degrees F. Approvals include ASME B 16.39 along with UL and FM listings.

Installers needing a 3/8 inch threaded union

This union suits pipefitters assembling steam or hydronic systems that require a 3/8 inch FNPT connection with brass seating. It is not for systems demanding larger pipe sizes, different thread types, or pressure classes above Class 150. Buyers who need welded ends, socket weld, or flanged connections must select alternative fittings.

Brass seat material for 3/8 inch FNPT union

The brass seat provides the sealing surface inside the malleable iron union body. This material choice affects compatibility with the fluid media and determines leak-tight performance at the rated pressures. Verify that brass is acceptable for the specific application before installation.

Highlights

  • Rated for 300 psi working pressure at 150 °F
  • Handles saturated steam up to 150 psi for demanding systems
  • Operates reliably from –20 °F to 350 °F across seasons
  • Brass seat resists corrosion and ensures tight sealing
  • Meets ASME B16.39 with UL and FM approvals

Specifications

BrandANVIL

Questions about this item

What thread type must the pipe already have to connect to the 3/8 in FNPT ends of this union?

The pipe needs male NPT threads so the union's female NPT ends can screw on and seal properly.

Can the brass seat and malleable iron body handle the same 300 psi at 150 °F rating when paired with older steel pipe?

Yes, the union is rated for 300 psi at 150 °F and meets ASME B16.39, so it matches the pressure class of standard Class 150 steel piping.

How can I confirm the union is seated correctly after assembly?

Tighten until the brass seat makes metal-to-metal contact and no leakage appears when the system is pressurised up to the 300 psi rating.

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