Reducing Tee, Slip x Slip x FPT PVC Schedule 40 3" x 3" x 1" (402-335)

The 402-335 is a 3-inch Schedule 40 PVC reducing tee with slip (socket) connections on both run ends and a 1-inch female pipe thread (FPT) connection on the branch outlet. Within the 402-series family of 3-inch reducing tees, the 1-inch FPT branch occupies a practical middle ground: larger than the 1/2-inch and 3/4-inch branches suited for pure instrumentation and injection work, but not a full-bore distribution branch like the 2-inch. At 1-inch NPT, the branch is sized to carry modest but real flow volume — serving small service connections, low-volume bypass lines, chemical treatment feeds with actual throughput requirements, manual drain valves where drainage speed matters, and small-zone supply takeoffs that need more capacity than a 3/4-inch port can reliably deliver.

The 3" x 3" run passes full mainline flow through the fitting body with no reduction, while the 1-inch FPT branch provides a direct threaded port accepting standard male NPT pipe, valves, and fittings without an intermediate reducer or adapter. The 1-inch NPT thread form is one of the most universally available connection sizes across PVC, CPVC, brass, and stainless fittings — ball valves, check valves, male adapters, hose bibs, solenoid valve bodies, and flow control devices are all readily available in 1-inch NPT — making the branch assembly straightforward with no size-matching complications.

The mixed connection architecture — permanent solvent weld on the 3-inch run, threaded on the 1-inch branch — follows the same logic as the broader 402-series design: the mainline is a fixed, permanently routed installation while the branch connection serves equipment or a valve that may need to be serviced, isolated, or reconfigured over the system's life. The threaded branch can be broken and remade independently without disturbing the solvent welded run.

Both 3-inch run ends require heavy-bodied PVC solvent cement applied thoroughly and quickly to both the pipe end and socket bore. Pipe should be seated immediately with a quarter-turn rotation to distribute cement evenly, then held firmly for 30 seconds. Allow a full 24-hour cure before pressurizing the system. The 1-inch FPT branch accepts male NPT fittings assembled with PTFE thread tape or appropriate thread sealant — do not overtighten threaded connections into PVC female threads.

This fitting is manufactured from virgin PVC compound conforming to ASTM D1784 Cell Classification 12454 and dimensioned to ASTM D2466 standards for Schedule 40 PVC socket fittings.

Specifications:

Pressure rating is for water service at 73°F. Derate for elevated temperatures per manufacturer guidelines. Use heavy-bodied PVC solvent cement for 3-inch socket joints. Use PTFE thread tape or appropriate thread sealant on the 1" FPT branch — do not overtighten threaded connections into PVC female threads.

Industries & Applications:

The 402-335 reducing tee is specified wherever a 3-inch Schedule 40 PVC mainline requires a 1-inch threaded branch capable of handling modest but real flow volume for service connections, bypass feeds, or low-volume process takeoffs:

• Irrigation & Agricultural Distribution — Small-zone supply connections and bypass feeds on 3-inch irrigation headers where a 1-inch threaded branch delivers adequate flow to small zone valves, fertigation injectors with meaningful throughput requirements, and manual flush valves that need more capacity than a 3/4-inch port provides
• Chemical Processing & Water Treatment — Low-volume chemical treatment branch feeds on 3-inch process and distribution headers where a 1-inch threaded takeoff supplies chemical treatment skids, bypass treatment loops, or secondary dosing equipment with flow volumes that exceed the capacity of smaller instrumentation-grade branch ports
• Municipal & Commercial Plumbing — Service taps, hose bibb connections, and secondary supply branches on 3-inch utility water mains and mechanical room headers where a 1-inch threaded port serves fixtures, equipment connections, and small distribution branches requiring more than minor flow capacity
• Pump & Filtration Systems — Bypass line connections and low-volume recirculation branches on 3-inch pump discharge headers where a 1-inch FPT branch supplies bypass flow control valves, filter backwash lines, or secondary loop feeds without full-bore branch piping
• Industrial Process Piping — Secondary process feed takeoffs and service branch connections on 3-inch reagent distribution and utility water headers where 1-inch threaded branch connections supply downstream equipment, sampling stations, and low-volume process lines
• Swimming Pool & Aquatic Facility Plumbing — Bypass feeds, chemical treatment equipment connections, and small-bore service branches on 3-inch pool recirculation mains where a 1-inch FPT branch accommodates side-stream treatment equipment and low-volume auxiliary connections
• HVAC & Cooling Systems — Chemical treatment side-stream connections and low-volume bypass feeds on 3-inch condenser water and cooling tower supply headers where a 1-inch threaded branch serves treatment equipment and secondary loop connections in mechanical room installations
• Drain & Flush Connections — Low-point drain branches on 3-inch pressurized mainlines where a 1-inch ball valve or drain fitting provides faster, higher-capacity system draindown than a 1/2-inch or 3/4-inch drain port when maintenance timelines are a priority