Bushing, Spigot x Slip (Flush Style) PVC Schedule 80 12" x 10" (837-670)

The 12" x 10" PVC Schedule 80 Bushing (Spigot x Slip, Flush Style), Part #837-670, is a heavy-wall, large-diameter reducing bushing engineered to adapt a 12-inch slip-socket fitting down to accept a 10-inch pipe or spigot connection. Manufactured from Type I, Grade I PVC compound to ASTM D2467 specifications, this fitting delivers Schedule 80's elevated pressure rating, increased wall thickness, and broad chemical resistance — making it the correct specification for industrial process, chemical handling, and high-demand municipal infrastructure where engineering drawings mandate Schedule 80 throughout or where operating conditions exceed Schedule 40's practical limits.

The spigot x slip connection defines how this bushing integrates into an existing system: the spigot (male, plain) end is dimensioned to insert directly into a 12-inch slip socket on an existing fitting, valve, or equipment port, bonded in place with solvent cement; the slip (female, socket) end then receives a 10-inch pipe or spigot fitting, also solvent welded. This in-socket configuration eliminates the need for a separate reducer coupling when a 12-inch slip socket is already present in the line — consolidating what would otherwise be a two-fitting assembly into a single, compact, purpose-built reducer.

The flush style body is an important specification distinction, particularly at this diameter range. Unlike hex (flanged) bushings, which protrude beyond the face of the mating socket and can create clearance conflicts or impose mechanical stress at the joint, the flush bushing body sits fully recessed within the 12-inch socket. At large diameters, this low-profile geometry is especially practical — hex flanges become proportionally more obstructive as pipe size increases, making flush-style bushings the preferred choice for buried installations, vault assemblies, tight mechanical spaces, and manifold configurations where fitting geometry must remain within the envelope of the mating socket.

The 12" x 10" size relationship is notable among large-diameter bushings in that the outlet represents a relatively modest reduction from the inlet — a step-down of two nominal pipe sizes rather than the more dramatic reductions seen in 12x8 or 12x4 configurations. This makes Part #837-670 particularly well suited for systems where flow capacity must be preserved as much as possible through the transition, and where the downstream circuit operates at only slightly reduced capacity from the primary 12-inch main. For any existing 12-inch slip socket that must feed a 10-inch downstream run, this fitting provides a direct, specification-compliant, single-piece solution without modifying the upstream fitting or adding a reducer coupling to the assembly.

Specifications:

Note: Pressure ratings for large-diameter PVC fittings decrease relative to smaller sizes and are further reduced at operating temperatures above 73°F. Consult ASTM D2467 pressure derating curves and applicable engineering specifications before installation in high-pressure or elevated-temperature service. Although the 12" x 10" transition is a relatively modest reduction, flow velocity changes and minor pressure loss at the transition should still be accounted for in hydraulic design. Proper large-diameter solvent weld technique — including surface preparation, primer application, and adequate cure time — is essential at this pipe size to achieve full joint integrity.

Industries & Applications:

• Municipal Water Distribution — In-socket diameter transitions on 12-inch transmission and distribution mains where a 10-inch branch, sub-main, or zone feed must be taken off an existing 12-inch slip-socket fitting, valve, or tee without adding a reducer coupling to the assembly.
• Industrial Process Piping — Large-diameter in-socket reductions at valves, equipment ports, and manifold connections in chemical plants, refineries, and manufacturing facilities where Schedule 80 is the baseline specification and minimal flow restriction through the transition is a design priority.
• Chemical Handling & Water Treatment — Reducer bushings for treatment plant distribution headers, chemical feed manifolds, and process piping systems where PVC's resistance to acids, caustics, and chlorinated media is a primary material driver and Schedule 80 wall thickness is required by engineering specification.
• Industrial Valve Manifolds — Adapting large-bore valve bodies with 12-inch slip ports to 10-inch downstream piping in systems where the modest size reduction preserves flow capacity through the valve assembly while stepping down to the downstream circuit size.
• Wastewater & Force Main Infrastructure — Pressurized force main connections, pump station discharge manifolds, and large-diameter lateral transitions where a 12-inch fitting socket must step down to a 10-inch branch or service run under Schedule 80 specification.
• Irrigation & Agricultural Systems — High-pressure mainline manifold transitions where 12-inch supply headers feed 10-inch zone or sector circuits — a common configuration on large-scale agricultural or golf course systems where the relatively small size differential minimizes pressure drop across the transition.
• HVAC & Mechanical Systems — Chilled water mains, condenser water loops, and cooling tower supply and return piping in large commercial and industrial facilities where 12-inch distribution headers must reduce to 10-inch equipment or branch feeds within tight mechanical room or rooftop equipment assemblies.
• Power Generation & Heavy Industrial — Cooling water intakes, service water mains, and plant utility connections at large-diameter headers in power plants, petrochemical facilities, and heavy process installations where Schedule 80 is the facility-wide piping specification.
• Mining & Aggregate Processing — Process water and dewatering system piping requiring large-diameter corrosion-resistant in-socket reduction in aggressive or abrasive operating environments where the 12-to-10-inch transition preserves maximum flow capacity through the system.