Bushing, Spigot x Socket PVC Schedule 40 4" x 1-1/2" (437-419)

The 437-419 is a Schedule 40 PVC reducing bushing with a 4-inch spigot (plain end) and a 1-1/2-inch socket (slip) outlet. The spigot end solvent cements directly into any standard 4" Schedule 40 or Schedule 80 PVC socket fitting, while the socket outlet accepts the outside diameter of standard 1-1/2" Schedule 40 or Schedule 80 PVC pipe via solvent cement — producing a fully cemented, permanent transition from a large-diameter pipeline to a substantial-bore solvent-welded branch, lateral feed, or secondary circuit without introducing a threaded joint at the reduction point.

As the largest outlet size in the standard 437 series 4" inlet sub-series, the 437-419 is well positioned for applications where the downstream branch must carry significant flow — secondary supply mains, high-flow bypass circuits, pump suction branches, and equipment inlet feeds where a 1-1/2" cemented pipe run is the specified downstream configuration. The relatively modest size differential between the 4" inlet and 1-1/2" outlet also makes this bushing one of the more hydraulically efficient reductions in the 4" sub-series, minimizing turbulence and pressure drop at the transition point compared to more aggressive step-downs. Where a 1-1/2" female threaded outlet is needed at the same 4" inlet, the 438-419 (Spigot x FPT, 4" x 1-1/2") is the corresponding alternative.

For the 4" spigot end, use an IPS-grade, heavy-bodied solvent cement and a medium-bodied PVC primer per ASTM D2564 — for 4" and larger joints, a two-coat application is recommended to ensure full socket penetration and a reliable, leak-free bond. The 1-1/2" socket outlet follows standard primer-and-cement procedure for small-diameter PVC joints; ensure full pipe insertion to the socket stop and maintain joint alignment during the cure set period.

Specifications:

Industries & Applications:

• Municipal & Commercial Plumbing — Reduces a 4" cemented main line socket to a 1-1/2" solvent-cemented branch for high-flow secondary supply circuits, zone mains, or service connections in commercial plumbing systems where a fully bonded all-cement transition is specified.
• Water Treatment & Distribution — Provides a cemented high-flow branch connection on large-diameter PVC distribution and treatment system pipelines for bypass circuits, secondary treatment feeds, or flow diversion runs within fully solvent-welded assemblies.
• Irrigation & Agricultural Systems — Used at pump discharge headers, filter manifolds, and mainline distribution points where a 4" cemented inlet must reduce to a 1-1/2" cemented outlet for high-flow lateral zone mains, pressure regulator feeds, or secondary distribution circuits.
• Industrial Process Piping — Adapts large-diameter PVC process lines to 1-1/2" cemented branch connections for secondary process circuits, high-flow bypass loops, or substantial-bore equipment inlet feeds in fully solvent-welded corrosion-resistant systems.
• Pool & Spa Plumbing — Transitions 4" suction or return headers to 1-1/2" cemented branch connections for auxiliary circulation circuits, spa side-stream feeds, or secondary equipment supply lines in high-flow pool and spa installations.
• HVAC & Chilled Water Systems — Connects 4" PVC drainage or secondary piping to 1-1/2" cemented branch lines for high-flow drain circuits, secondary equipment connections, or condensate collection mains on commercial mechanical systems.