Reducer Coupling, Slip 10" x 8" (C629-628)

The 10" x 8" PVC Class 125 Reducer Coupling (Part No. C629-628) is a large-diameter, white-body fitting designed to transition a 10" solvent-cemented PVC pipe run down to an 8" pipe in a single inline component. Both the larger and smaller ends accept solvent-cement joints in a slip (socket) configuration, producing a rigid, leak-resistant connection suited to the high-volume flow applications and large-scale infrastructure environments where large-diameter PVC is specified.

Reducer couplings are the most compact and straightforward approach to an inline pipe size reduction — combining the transition into a single fitting rather than pairing a standard coupling with a separate bushing or a pair of adapters, minimizing installed length, joint count, and potential leak points in the assembly. At the 10" × 8" size combination, this efficiency is particularly meaningful: large-diameter fittings carry significant material and labor cost, and consolidating a two-size step-down into one fitting rather than a multi-piece assembly represents a real installation and cost advantage on long runs and large projects.

The 10" × 8" size combination appears most frequently in municipal water distribution and transmission systems, large-scale agricultural and landscape irrigation mains, industrial process water systems, and stormwater infrastructure — applications where the main line steps down from a 10" trunk or header to an 8" distribution or lateral run. At these diameters, PVC is specified for its corrosion resistance, hydraulic smoothness, long service life, and cost efficiency relative to ductile iron or steel alternatives in non-pressure-class applications.

As a Class 125 fitting, this product is part of the C-prefix series in Charlotte Pipe's large-diameter PVC lineup — a designation that should be verified against the manufacturer's current catalog to confirm pressure class, dimensional standard, and applicable use conditions before specifying for pressure-rated applications.

Manufactured from Type I, Grade I PVC compound and conforming to ASTM D2466 dimensional standards, this fitting is compatible with the corresponding Schedule 40 or Class 125 PVC pipe and solvent cements meeting ASTM D2564.

Specifications:

Industries & Applications:

• Municipal Water Distribution — Inline reductions from 10" transmission or trunk mains to 8" distribution lines at system branch points, zone entries, and pressure district boundaries
• Large-Scale Irrigation — Step-down transitions from 10" agricultural or landscape irrigation mains to 8" lateral distribution headers at zone manifolds and field distribution points
• Industrial Process Water — High-volume process water and cooling water systems where a 10" supply main steps down to an 8" distribution run at equipment headers or facility entry points
• Stormwater & Site Drainage — Large-diameter stormwater conveyance systems requiring an inline size reduction between 10" and 8" collection or discharge pipe sections
• Water & Wastewater Treatment — Plant distribution and collection piping where large-diameter PVC mains transition between sizes at treatment process connections or effluent distribution points
• Power Generation & Utilities — Cooling water intake and discharge systems where 10" to 8" reductions are required at pump discharge headers or distribution manifolds
• Commercial & Institutional Construction — Large-site utility and fire suppression system mains where an inline 10" × 8" reduction is required at system zone entries or building service connections