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Four-inch stainless steel union fitting with threaded ends

Legend Valve

Legend Valve 404-151 4" SS304 Union equipment

SKU CH-8ZQH-ARDRE

Four-inch 304 stainless steel union with FNPT threads for industrial plumbing systems

  • Stainless steel construction resists corrosion in demanding systems
  • 4-inch FNPT connection fits standard industrial pipe threads
  • 304-grade material handles high-temperature and chemical exposure
  • Union design allows quick disassembly for maintenance
  • New condition ensures full factory specification performance

4-Inch 304 Stainless Steel Union

This Legend Valve 404-151 union connects two sections of piping using female NPT threads. The 304 stainless steel body resists corrosion in water, chemical and general industrial systems. It is supplied new and ready for installation in compatible pipework.

Industrial and Commercial Pipework Installers

The union suits technicians who need a removable joint on 4-inch lines with FNPT connections. It does not serve installers working with metric threads, socket-weld ends or larger nominal diameters. Buyers requiring a different alloy or pressure class must select an alternative fitting.

304 Stainless Steel Material Grade

The 304 stainless steel construction determines chemical compatibility and corrosion resistance for the intended fluid. California Proposition 65 notices indicate the product contains chemicals known to cause cancer and reproductive harm. Verify that the material grade meets the service requirements before fitting.

Highlights

  • Stainless steel construction resists corrosion in demanding systems
  • 4-inch FNPT connection fits standard industrial pipe threads
  • 304-grade material handles high-temperature and chemical exposure
  • Union design allows quick disassembly for maintenance
  • New condition ensures full factory specification performance

Specifications

BrandLEGEND VALVE

Questions about this item

How do I install the 4" SS304 union and what step is often missed?

Thread the FNPT ends onto matching pipe threads with sealant, then tighten the union nut fully; the step often missed is seating the gasket before final tightening.

What maintenance or replacement will the 404-151 union need later?

Inspect the 304 stainless steel gasket periodically and replace it if leaks appear or during scheduled system maintenance.

What limit appears first on the 4" union under sustained pressure?

The 304 stainless steel body and FNPT threads set the pressure limit; sustained use near that rating can cause thread deformation first.

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