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

6 inch x 4 inch PVC S&D Reducing Coupling – Hub x Hub Transition for Gravity Drainage Systems

The 6 inch x 4 inch PVC Sewer & Drain (S&D) Reducing Coupling is a molded fitting designed for use in non-pressurized gravity flow systems. It allows for smooth transition between 6-inch and 4-inch nominal diameter S&D piping, providing a secure hub-to-hub connection in both new construction and retrofit drainage configurations.

Manufactured from high-strength polyvinyl chloride (PVC), this coupling conforms to ASTM and SDR specifications for S&D applications. Its socket ends are engineered to accept standard SDR-35 or ASTM D3034 pipe, making it ideal for stormwater runoff, landscape drainage, or sanitary lateral reductions in underground piping systems.

Key Attributes for Professional Applications

• ✅ Dimensional Compatibility – Designed to connect 6 inch and 4 inch SDR S&D pipe using solvent weld hub ends for uniform joint integrity.
• ✅ Durable PVC Body – Provides chemical resistance, impact strength, and long service life in underground conditions.
• ✅ Leak-Resistant Profile – Hub geometry ensures proper pipe insertion depth for consistent solvent weld adhesion and sealing.
• ✅ Gravity-Flow Rated – Suitable for unpressurized systems such as stormwater, gray water, and sanitary sewer laterals.
• ✅ Code Compliant – Conforms to ASTM D3034 and ASTM D3212 for joint performance and dimensional standards.

Technical Specifications

• Material: PVC (Polyvinyl Chloride)
• Nominal Sizes: 6 inch x 4 inch
• Connection Type: Hub x Hub (solvent weld)
• Standards: ASTM D3034, ASTM D3212, applicable to SDR 35 systems
• Application: Non-pressurized sewer and drainage systems

Installation Considerations

Cut and bevel pipe ends to required length and remove burrs. Dry-fit the coupling to verify alignment, then apply PVC solvent cement to both pipe and socket per ASTM D2855 guidelines. Insert pipe fully to the hub stop and hold briefly to ensure bond. Allow for proper cure time before system testing or backfilling.

Common Uses

This reducing coupling is commonly installed in municipal sewer lines, stormwater systems, site drainage networks, and lateral connections where a size transition is required between 6 inch and 4 inch piping. Also suitable for utility site drainage in commercial and residential developments.

Material Note

PVC is lightweight, chemically inert, and resistant to root intrusion, making it a preferred material in buried drainage applications with minimal maintenance demands.

The 6 inch x 4 inch PVC S&D Reducing Coupling is an essential component for size-reducing transitions in non-pressurized drain systems. Designed for longevity, code compliance, and ease of installation, it supports consistent system performance across a wide range of site and utility conditions.