Coupling, Slip x Slip PVC Schedule 80 1-1/4" (829-012)

This 1-1/4" Schedule 80 PVC Coupling provides a permanent, pressure-rated inline joint between two sections of 1-1/4" PVC pipe in solvent-cemented Schedule 80 pressure piping systems. Both slip socket ends accept standard 1-1/4" PVC pipe for solvent cement joining, producing a continuous, straight-run connection that maintains full system pressure rating through the joint.

At 1-1/4", this coupling serves a pipe size that occupies a well-defined transitional position in commercial and industrial piping layouts. Where 1" pipe falls short of the flow capacity required for a secondary header, equipment supply run, or branch main — and where 1-1/2" introduces more capacity than the application demands — 1-1/4" fills the gap. The result is a pipe size regularly encountered at pump suction lines, equipment feed connections, secondary distribution headers, and branch supply mains in mechanical rooms, process facilities, and water treatment systems. The 829-012 is the foundational joining fitting at every pipe-length extension, field repair, and section-to-section connection in those runs.

The coupling serves three core functions in any PVC piping system: extending a pipe run by joining two pipe lengths end to end, connecting pipe to other slip socket fittings at either socket end, and providing a repair joint when a damaged or compromised section of pipe must be cut out and replaced. In established Schedule 80 systems, using a Schedule 80 coupling at repair and extension points preserves pressure rating consistency through the joint — substituting a Schedule 40 coupling in a Schedule 80 line introduces a pressure rating discontinuity at the repair location that the 829-012 eliminates.

Manufactured in dark gray Schedule 80 PVC, this coupling delivers the increased wall thickness and mechanical strength required in industrial, chemical, and commercial pressure piping where Schedule 40 ratings are insufficient. PVC's broad chemical resistance covers acids, bases, salts, chlorine, and most common process fluids, providing long service life in corrosive environments where metal couplings would degrade, corrode, or introduce contamination into the fluid stream. NSF/ANSI 61 listing confirms suitability for potable water contact.

Rated to 630 psi at 73°F, this coupling handles standard to elevated pressure service across a wide range of fluid handling applications. For installation, clean and dry both pipe ends and socket interiors before application. Apply purple PVC primer to all mating surfaces, then apply a uniform coat of Schedule 80 PVC solvent cement to both the pipe end and socket interior before joining. Insert the pipe with a slight quarter-turn twist and hold firmly for 30 seconds to prevent pushback. Stagger the two joints where possible and allow full cure time per the cement manufacturer's temperature and humidity guidelines before pressurizing. Apply published pressure derating factors for service temperatures above 73°F.

Specifications:

Industries & Applications:

• Industrial Process Piping — Joins 1-1/4" Schedule 80 PVC pipe sections end to end on secondary process headers, equipment supply lines, pump suction and discharge runs, and chemical distribution branches in water treatment, chemical processing, and manufacturing facilities; provides schedule-consistent repair joints when pipe sections require replacement in existing Schedule 80 systems
• Commercial Plumbing — Extends and repairs 1-1/4" Schedule 80 PVC runs at branch supply mains, equipment feed connections, and secondary distribution headers in mechanical rooms, utility chases, and building water distribution systems where the intermediate pipe size and Schedule 80 pressure rating are both specified
• Pump Suction & Equipment Supply Piping — Provides inline pipe continuity on 1-1/4" Schedule 80 PVC pump suction lines, equipment feed connections, and process instrument supply headers where the 1-1/4" pipe size is selected to balance flow velocity and fitting pressure loss at equipment inlet connections
• Water & Wastewater Treatment — Maintains inline pipe continuity on 1-1/4" Schedule 80 PVC process headers at filter vessel connections, chemical dosing supply lines, pump suction runs, and sampling manifold feeds in municipal and industrial water treatment facilities
• Chemical Handling — Provides a corrosion-resistant, schedule-consistent joining point on 1-1/4" chemical feed lines, reagent distribution branches, and tank recirculation loops in systems conveying acids, caustics, fertilizer solutions, and other aggressive fluids where metal couplings would degrade or contaminate the process stream
• Irrigation & Agricultural Systems — Joins and repairs 1-1/4" Schedule 80 PVC pressure mains and secondary headers in high-pressure commercial irrigation systems, greenhouse supply networks, and agricultural water distribution where the 1-1/4" pipe size bridges the flow requirement between smaller 1" laterals and larger 1-1/2" mains
• HVAC & Mechanical Systems — Used in PVC cooling tower makeup lines, chilled water drain headers, glycol distribution branches, and treated water secondary piping where a schedule-consistent 1-1/4" slip coupling maintains full pressure rating through the joint in Schedule 80 mechanical system piping