Reducer Bushing, Spigot x Slip 10" x 8" (C637-628)

The 10" x 8" PVC Class 125 Reducer Bushing (Spigot x Slip) is a large-diameter thermoplastic inline reducer designed to transition from a 10-inch fitting connection point to an 8-inch downstream pipe run within a single compact fitting body. The 10-inch spigot end is a plain male outer-diameter that inserts directly into any standard 10-inch Class 125 slip socket fitting, while the 8-inch slip socket on the outlet end accepts 8-inch Class 125 PVC pipe for permanent solvent cement installation. The result is a two-size step-down — from 10 inches to 8 inches — accomplished entirely within the socket of an existing fitting, without a separate reducer coupling, additional fittings, or extra pipe sections consuming space in the assembly.

The 10" to 8" size differential is a moderate, practical reduction that appears frequently in large-diameter drainage networks where a primary collection main steps down to a smaller conveyance run as the accumulated flow load decreases along the system — or where a larger header fitting must supply a smaller downstream pipe without the alignment complexity and additional joint count that a standalone reducer coupling would introduce. At this scale, the bushing's compact geometry is particularly valuable: a 10" x 8" reducer coupling in open pipe requires two cemented joints and its own linear footprint in the run, while a spigot bushing inserted into the socket of an existing 10-inch tee, coupling, or elbow outlet accomplishes the same reduction in zero additional pipe length and with two fewer joints in the assembly.

Class 125 PVC fittings are dimensioned to the cast iron pipe fitting pattern — the correct standard for large-diameter drainage, stormwater conveyance, and gravity-flow applications where cast iron fitting geometry is specified or where PVC is being installed as a corrosion-resistant alternative within existing cast iron infrastructure. This dimensional standard differs from Schedule 40 PVC and the two are not interchangeable at the fitting level in applications governed by cast iron pattern geometry. At both the 10-inch spigot end and the 8-inch slip socket, this bushing is dimensioned to Class 125 / cast iron pattern standards, ensuring full compatibility with mating Class 125 components in both sizes. Manufactured to ASTM D2466 standards.

Specifications:

Industries & Applications:

• Municipal Drainage & Stormwater — The core application for a large-diameter Class 125 reducer bushing; used at 10-inch fitting outlets in underground stormwater collection networks where the downstream run steps down to 8 inches — accomplishing the reduction within the existing 10-inch fitting socket rather than mid-run, reducing joint count and assembly length in buried systems where excavation access is limited
• Large Commercial Building Drainage — Specified in below-grade gravity drain mains for large commercial, institutional, and industrial buildings where a 10-inch primary drain fitting must transition to an 8-inch downstream lateral or branch run at a tee outlet, coupling end, or other 10-inch fitting socket in the assembly
• Civil & Site Utilities — Incorporated in site utility plans for commercial developments and infrastructure projects where underground 10-inch drainage or stormwater fittings must supply 8-inch downstream runs — using the bushing in the fitting socket to minimize fitting count and assembly length at the reduction point in buried utility corridors
• Cast Iron System Replacement & Retrofit — Applied in cast iron drainage system upgrades where a 10-inch cast iron fitting outlet must transition to an 8-inch PVC downstream run; the Class 125 spigot end matches the cast iron pattern socket dimensions, allowing the bushing to seat in an existing cast iron fitting socket during a phased retrofit without requiring a custom transition fitting
• Industrial Discharge & Process Drainage — Used in large-bore industrial drain and process discharge systems where a 10-inch collection header fitting must supply an 8-inch conveyance run to a lower-load downstream discharge point, treatment connection, or secondary collection main
• Water & Wastewater Treatment Facilities — Incorporated in gravity drainage, process drain, and effluent conveyance lines within treatment plant infrastructure where 10-inch fitting outlets must transition to 8-inch downstream pipe runs between process areas or treatment stages — using the bushing to accomplish the reduction compactly within the existing fitting socket rather than as a separate reducer in the open run