Coupling, Slip x Slip PVC Schedule 40 1-1/4" (429-012)

This 1-1/4" Schedule 40 PVC Coupling (Slip x Slip) provides a straight-through inline connection for two 1-1/4" PVC pipe ends in all-socket piping systems — the standard fitting for joining, extending, or repairing 1-1/4" all-cemented PVC pipe runs without introducing directional changes or size reductions into the assembly. Constructed in white Schedule 40 PVC, it offers the corrosion resistance and chemical compatibility required across a wide range of commercial plumbing, irrigation sub-main, and light industrial fluid handling applications where all-socket cemented construction is specified or preferred throughout the system at the common intermediate distribution diameter.

Both the inlet and outlet are 1-1/4" slip socket ends, each accepting the exterior of a standard 1-1/4" PVC pipe end for a permanent solvent-cement bond per ASTM D2564 procedures — creating a continuous, leak-free inline connection at each cemented joint. As the fundamental straight-through connector in all-socket PVC assemblies at this diameter, the slip coupling joins two pipe ends in a continuous inline run — at pipe extension joints where a sub-main run must be lengthened beyond available pipe section lengths, at cut-in repair sections where a damaged intermediate pipe segment must be replaced inline, at system boundary transitions where two pre-assembled pipe sections must be joined at the final connection point, and at distribution assembly connection points where two 1-1/4" pipe run sections must be joined without a direction change. The slip coupling requires pipe ends on both sides — it should not be confused with the FPT x FPT threaded coupling (430-012 confirmed in this catalog session), which joins two male-threaded components rather than cementing to pipe ends; with the female adapter (435-012 confirmed), which terminates a socket run at a female-threaded outlet for a male-threaded component; with the male adapter (436-012 confirmed), which terminates a socket run at a male-threaded outlet for threading into a female-threaded port; or with the full-size 429-015 (1-1/2" Slip Coupling) at the adjacent larger diameter. At 1-1/4", this coupling is among the most widely specified inline connectors at the intermediate distribution diameter — appearing throughout commercial irrigation sub-main extension and repair assemblies, commercial plumbing branch supply distribution headers, pump station socket piping, and light industrial process water socket assemblies where 1-1/4" is the standard intermediate mainline diameter requiring straight-through inline connections at multiple pipe run joining points throughout the system.

Rated to approximately 370 psi at 73°F, this coupling 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 couplings 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 exterior and the fitting socket interior per ASTM D2564 procedures at each port, using a primer appropriate for the pipe and fitting schedule. Insert pipe fully into each socket and maintain a quarter-turn during assembly for even cement distribution. Allow adequate cure time before pressurizing the system, and derate pressure ratings for elevated temperatures per published derating curves.

Specifications:

Industries & Applications:

• Irrigation & Water Distribution — Joins, extends, and repairs 1-1/4" socket sub-main and secondary distribution pipe runs at pipe extension joints, cut-in repair sections, and assembly boundary connection points in agricultural and municipal irrigation systems where all-socket cemented construction is maintained throughout and a straight-through inline connection at the intermediate sub-main diameter is required without direction change or size reduction at the joint
• Commercial Plumbing — Provides straight-through inline connections between 1-1/4" socket PVC pipe run sections at extension joints, repair connections, and distribution header assembly boundary points in commercial building water distribution systems where all-socket PVC construction is specified and a continuous inline connection maintains full intermediate mainline flow capacity through the coupling body
• Pump Station Assemblies — Joins 1-1/4" socket pump station discharge header pipe sections, suction line approach run segments, and bypass line pipe run sections at inline connection points in pump station installations where all-socket Schedule 40 PVC construction is maintained and straight-through pipe joining is required at multiple assembly and extension points throughout the pump station piping layout
• Industrial Process Piping — Connects and extends 1-1/4" socket process water distribution pipe runs, equipment feed approach lines, and service manifold supply pipe sections at inline joining points in water treatment, chemical processing, and manufacturing facilities where all-cemented Schedule 40 PVC construction requires straight-through inline connections at pipe run extension and repair points throughout the system
• Chemical Handling — Provides a corrosion-resistant straight-through inline connection between 1-1/4" socket pipe run sections in chemical distribution assemblies, pump station socket piping, and feed line headers conveying acids, caustics, fertilizer solutions, and other fluids incompatible with metal couplings — the permanent solvent-cement bond providing equivalent long-term chemical resistance to the fitting body itself at each connected pipe joint
• Water Treatment & Aquaculture — Used at inline straight-through pipe joining points on 1-1/4" all-socket distribution runs, chemical dosing manifold supply pipe sections, and treatment system intermediate distribution pipe assemblies where NSF/ANSI 61 compliance and chemical resistance are required at every cemented pipe-to-fitting connection throughout the all-socket assembly