Reducing Male Adapter, MPT x Slip PVC Schedule 40 1" x 1-1/4" (436-132)

This 1-1/4" x 1" Schedule 40 PVC Reducing Male Adapter (MPT x Slip) combines a pipe-size reduction and a socket-to-male-thread transition into a single compact fitting body, accepting a 1-1/4" PVC pipe run at the slip socket end and providing a 1" male NPT thread at the outlet — eliminating the need for a separate full-size male adapter plus an inline reducer coupling at the same assembly location. Constructed in white Schedule 40 PVC, it offers the corrosion resistance and chemical compatibility required across a wide range of commercial plumbing, irrigation, and light industrial applications where a 1-1/4" socket pipe run must terminate at a 1" female-threaded port, valve body, equipment inlet, or threaded pipe run without additional transition hardware.

The 1-1/4" slip socket accepts 1-1/4" PVC pipe for a permanent solvent-cement bond, maintaining the full upstream pipe diameter at the socket inlet. The 1" MPT exterior threads directly into any standard 1" FPT or FIP female-threaded fitting, valve body, pump port, or equipment connection using NPT tapered thread geometry. This reducing configuration makes the fitting the correct single-fitting solution when a 1-1/4" socket distribution run must connect to a 1" female-threaded system component — combining the size reduction and thread transition that a standard full-size male adapter plus a 1-1/4" x 1" reducer coupling would otherwise require. The 1-1/4" to 1" step-down is a very modest 1.25:1 near-full-size reduction — the least aggressive possible at this slip inlet diameter and driven primarily by the need to match a 1" threaded downstream component at a 1-1/4" socket pipe run rather than by any significant flow management requirement. This adapter is the smallest confirmed slip inlet entry in the 436 reducing sub-series and pairs directly with 436-133 (1-1/2" Slip x 1" MPT) at the same 1" MPT outlet — the correct choice when the upstream socket run is 1-1/4" rather than 1-1/2". At this combination, the fitting most commonly appears where 1" threaded zone valves, pump inlets, filter housings, or equipment connections are specified alongside a 1-1/4" socket pipe run in irrigation valve station assemblies, pump connections, and light commercial plumbing branch supply systems.

Rated to 370 psi at 73°F (governed by the 1-1/4" slip end), this adapter is suited for standard commercial and light industrial water distribution and irrigation service within its pressure class. Its PVC composition provides excellent resistance to corrosion, scale, chlorinated water, and a broad range of chemical exposures, making it a reliable long-term alternative to metal adapters in moisture-prone or chemically active environments. NSF/ANSI 61 listing confirms suitability for potable water contact.

Apply solvent cement to both the pipe end and fitting socket per ASTM D2564 procedures, using a primer appropriate for the pipe and fitting schedule. Insert pipe fully into the socket and maintain a quarter-turn during assembly for even cement distribution. On the 1" MPT end, use a quality pipe thread sealant or PTFE tape and avoid over-torquing — PVC threads require hand-tight plus one to two turns. Allow adequate cure time on the cemented joint before pressurizing the system, and derate pressure ratings for elevated temperatures per published derating curves.

Specifications:

Industries & Applications:

• Irrigation & Water Distribution — Terminates 1-1/4" PVC socket supply runs at 1" female-threaded zone control valves, pump inlets, filter housing connections, and valve station assemblies in agricultural and municipal irrigation systems where the downstream threaded component is specified at 1" while the upstream socket run is built to 1-1/4" — combining both the size reduction and thread transition in a single compact fitting
• Commercial Plumbing — Connects 1-1/4" Schedule 40 PVC socket distribution runs to 1" female-threaded valves, pressure-reducing assemblies, and equipment feed connections in commercial building water supply systems where a single reducing male adapter replaces a full-size adapter plus a separate reducer coupling at the pipe-to-thread transition point
• Industrial Process Piping — Transitions 1-1/4" socket PVC pipe runs to 1" female-threaded pump inlets, valve bodies, flow meters, and equipment ports in water treatment, chemical processing, and manufacturing facilities where a compact single-fitting near-full-size reducing thread transition minimizes fitting count at the pipe-to-equipment interface
• Chemical Handling — Provides a corrosion-resistant combined near-full-size reducing and socket-to-thread transition in systems conveying acids, caustics, fertilizer solutions, and other fluids incompatible with metal fittings, at pump inlets, valve stations, and chemical feed equipment interfaces where 1-1/4" socket PVC must connect to 1" female-threaded components in a single compact body
• Water Treatment & Aquaculture — Used at pump connection points, filter housing female-threaded inlets, and treatment equipment interfaces where a 1-1/4" socket pipe run must terminate at a 1" female-threaded component and NSF/ANSI 61 compliance is required throughout the system
• HVAC & Mechanical Systems — Connects 1-1/4" PVC socket pipe runs to 1" female-threaded pump ports, valve bodies, and equipment connections on cooling tower supply headers, chilled water distribution mains, and chemically treated water systems within the Schedule 40 pressure rating class