Reducing Coupling, Slip PVC Schedule 80 4" x 2-1/2" (829-421)

The 4" x 2-1/2" PVC Schedule 80 Reducing Coupling (829-421) delivers a direct, inline size transition from a 4" primary line down to a 2-1/2" continuation run in a single solvent-welded assembly — no intermediate reducers, no additional fittings, no added leak points at the transition. Both ends use slip (socket) connections for permanent, pressure-rated joints that maintain the full structural integrity of a Schedule 80 gray PVC system throughout.

Compared to the sharper 4" x 2" reduction of the 829-420, the 4" x 2-1/2" configuration represents a more moderate step-down — well suited to systems where flow capacity must be reduced at a transition point but the secondary run still requires meaningful throughput. This size pairing is a common design requirement in industrial process headers, chemical distribution systems, and commercial mechanical piping where a controlled, single-step inline reduction keeps the system layout clean and the fitting count low.

Manufactured to Schedule 80 specifications and dimensionally compliant with ASTM D2467, the 829-421 provides the elevated wall thickness and increased pressure rating that Schedule 80 gray PVC is specified for in chemical processing, industrial fluid handling, and demanding commercial environments. Gray PVC construction delivers broad chemical compatibility with acids, alkalis, and industrial process fluids where white Schedule 40 PVC is not suitable. NSF 61 certification confirms suitability for potable water contact where required.

Specifications:

Industries & Applications:

• Chemical Processing — controlled inline size reductions on chemical feed, dosing, and process fluid distribution headers where moderate flow reduction to a secondary run is required in a single fitting
• Industrial Process Piping — primary-to-secondary line reductions in plant utility, cooling water, and recirculating process systems requiring Schedule 80 pressure and chemical performance
• Water & Wastewater Treatment — inline reducing connections in treatment plant process piping where a moderate diameter step-down is specified and Schedule 80 is required for pressure or chemical compatibility
• Commercial & Industrial Plumbing — header-to-distribution inline reductions in high-pressure mechanical systems where Schedule 40 pressure ratings are insufficient for the application
• Aquaculture & Food Processing — corrosion-resistant inline size transitions in recirculating systems and sanitary or chemical-exposure fluid handling installations
• Irrigation & Agriculture — mainline-to-distribution inline reductions in high-pressure irrigation and chemical injection systems requiring a moderate flow step-down