6 inch x 4 inch PVC Sewer and Drain Reducing Coupling Hub x Hub

P658 S&D Coupling – 6 inch x 4 inch Hub x Hub Transition Fitting for Sewer and DWV Systems

The P658 S&D Coupling SWR H x DWV H 6 inch x 4 inch is a solvent-weld transition fitting used to connect 6-inch sewer pipe to 4-inch DWV (Drain, Waste, and Vent) pipe. Designed for non-pressurized systems, this coupling provides a reliable solution for joining dissimilar pipe diameters in sanitary drainage and stormwater applications.

Manufactured to ASTM and applicable municipal standards, this PVC coupling accommodates standard SDR 35 (Sewer) and ASTM D2665 (DWV) pipe dimensions. Its dual-hub configuration allows for solvent welding on both ends using approved primers and cements, ensuring a permanent, watertight seal in underground and above-grade installations.

Product Attributes

• ✅ Material: Injection-molded PVC, engineered for durability and chemical resistance in buried and above-ground drainage systems.
• ✅ Connection Type: Hub x Hub (Socket x Socket) solvent weld ends, sized to fit 6 inch SDR 35 and 4 inch DWV pipe.
• ✅ Application Range: Transition fitting for gravity sewer mains, residential lateral lines, and commercial DWV tie-ins.
• ✅ Operating Pressure: Rated for non-pressurized systems; tested under ASTM D3034 and D2665 for structural integrity and infiltration resistance.
• ✅ Size Compatibility: 6-inch x 4-inch nominal dimensions; suitable for step-down connections in new or retrofitted drainage systems.

Installation Requirements

Prior to installation, pipe ends must be chamfered and cleaned using CPVC/PVC-compatible primer. Apply solvent cement to both hub and spigot ends and insert fully to bottom-out depth. Allow proper set and cure time before backfilling or testing. All installation procedures must comply with local plumbing codes, and proper bedding is required in below-grade applications to prevent misalignment or joint stress.

Typical Use Cases

This coupling is used in stormwater drainage, municipal sanitary sewers, and DWV systems where a step-down transition from 6 inch to 4 inch is required. It is especially useful in residential and light commercial construction for lateral tie-ins, cleanout branches, and system modifications involving existing infrastructure.

Code & Compliance Note

Fittings used in gravity-flow DWV and S&D (Sewer & Drain) systems must meet dimensional and performance requirements outlined in ASTM D3034 (Sewer) and ASTM D2665 (DWV). This product meets those standards when properly installed and is approved for use in UPC and IPC jurisdictions.

Technical Specifications

• Nominal Size: 6 inch x 4 inch
• Fitting Type: Sewer x DWV Reducing Coupling
• Material: PVC, per ASTM D1784 (Cell Class 12454)
• Connection Method: Solvent weld (hub x hub)
• Standards: ASTM D3034 (Sewer), ASTM D2665 (DWV), NSF-listed for wastewater use