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Bronze inline swing check valve with FNPT ends

Milwaukee Valve

Milwaukee Valve 509 1 1/4" Swing Check Valve 3.5625" Overall Length

SKU CH-K5AY-HG4PD

Bronze inline swing check valve with FNPT connections, 54 gpm flow and 200 psi water rating at 150 °F

  • Size1 1/4"
  • TypeOther
  • Reliable flow control with 54 gpm capacity
  • Durable bronze body resists corrosion in plumbing systems
  • Handles temperatures from -20 to 406 degrees F
  • Low cracking pressure of .750 to 1.000 psi for smooth operation
  • Rated for 200 psi water pressure at 150 degrees F

Plumbing check valve

The Milwaukee Valve 509 is a 1 1/4 inch inline swing check valve with FNPT x FNPT connections. It uses a bronze body and a brass seat to allow flow in one direction while preventing backflow in residential and commercial piping systems.

Temperature and pressure limits

The valve operates from -20 degrees F to 406 degrees F and handles water pressure up to 200 psi at 150 degrees F. Steam service is rated at 125 psi WSP, and the cracking pressure ranges from .750 to 1.000 psi for reliable opening.

Sustained flow behaviour

Under continuous operation the valve delivers 54 gpm through its 3.5625 inch overall length. Horizontal or vertical mounting is supported, and the bronze seal maintains integrity across the full temperature range without the rapid wear seen in burst-only testing.

Highlights

  • Reliable flow control with 54 gpm capacity
  • Durable bronze body resists corrosion in plumbing systems
  • Handles temperatures from -20 to 406 degrees F
  • Low cracking pressure of .750 to 1.000 psi for smooth operation
  • Rated for 200 psi water pressure at 150 degrees F

Specifications

BrandMILWAUKEE VALVE
Size1 1/4"
TypeOther

Questions about this item

How do I install the 1 1/4" FNPT swing check valve and which orientation step is often missed?

Thread the FNPT ends onto 1 1/4" NPT pipe using sealant; the disc swings freely only when the hinge pin sits horizontally, so mount the valve with the cap facing up whether the run is horizontal or vertical.

Which parts of the bronze-body check valve will need inspection or replacement over time?

The bronze disc and brass seat seal the flow; mineral build-up or seat wear can let water leak back, so plan to clean or lap the seat and replace the disc if the 0.750 to 1.000 psi cracking pressure is no longer held.

What pressure or temperature limit will be reached first during continuous hot-water service?

The 200 psi rating at 150 °F governs steady hot-water use; steam service is capped at 125 psi, and the body maximum is 406 °F, so water pressure at temperature is the first constraint.

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