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Dayton 4RK70 ductile iron spring check valve 3 in MNPT x FNPT

Dayton

Dayton 4RK70 3 in MNPT x FNPT Ductile Iron Spring Check Valve Trap

SKU CH-H8N9-0M954 MPN 4RK70

Inline spring check valve in ductile iron with Buna-N seal rated to 180°F

  • TypeDrain Components
  • 3 in MNPT x FNPT connection fits directly into existing piping
  • Ductile iron body resists corrosion in general-purpose service
  • Inline spring mechanism closes automatically to prevent backflow
  • Stainless steel spring maintains reliable operation up to 180 Degrees F
  • Buna-N seal provides compatible sealing for water and oil applications

3-inch ductile iron check valve

This Dayton 4RK70 valve uses an inline spring mechanism to prevent reverse flow in piping systems. The ductile iron body and Buna-N seal suit general-purpose applications. Male and female NPT threads allow direct connection to 3-inch pipe.

Who this suits, who should look elsewhere

Installers needing a spring-loaded check valve with ductile iron construction for 3-inch NPT lines will find the required specifications here. Systems that require a steam pressure rating or a different seal material are not served by this model.

Maximum temperature 180 degrees F

The valve is rated for a maximum operating temperature of 180 degrees F, which determines whether it matches the thermal conditions of the intended installation. Exceeding this limit risks seal failure and loss of function.

Highlights

  • 3 in MNPT x FNPT connection fits directly into existing piping
  • Ductile iron body resists corrosion in general-purpose service
  • Inline spring mechanism closes automatically to prevent backflow
  • Stainless steel spring maintains reliable operation up to 180 Degrees F
  • Buna-N seal provides compatible sealing for water and oil applications

Specifications

TypeDrain Components
BrandDayton
Model4RK70

Questions about this item

What connections and seal does the 4RK70 use, and does it include pipe or fittings?

The valve has 3-inch MNPT x FNPT threads with a Buna-N seal. Pipe, nipples and thread sealant are not included and must be supplied separately.

The catalog lists only the 3-inch MNPT x FNPT version. How do I know this is the right size for my line?

Match the valve to your existing 3-inch NPT pipe threads. The ductile-iron body and stainless-steel spring are built for that nominal size; no other diameters or connection types are offered for this model.

The spec shows a 180 °F temperature limit and no steam rating. What does that mean for a hot-water return line?

The valve is rated to 180 °F, so it suits typical hot-water returns. It carries no steam-pressure rating, so do not install it on steam lines or where temperatures can exceed that limit.

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