Reducing Tee, Slip x Slip x Slip PVC Schedule 40 8" x 8" x 4" (401-582)

The 8" x 8" x 4" PVC Schedule 40 Reducing Tee (401-582) is a large-diameter, slip-socket fitting that delivers a 4" branch outlet directly off an 8" pipeline run in a single, solvent-welded component — eliminating the need to pair a full-size 8" tee with a separate downstream 8"x4" reducer to achieve the same branch configuration. With slip connections on all three ports, the 401-582 accepts solvent-welded Schedule 40 PVC pipe at both run ports and the branch outlet for a permanently bonded, full-pressure assembly across the entire fitting body at the run-to-branch transition point.

The two-size reduction from the 8" run to the 4" branch occupies a functionally important position in the 401 series — the 4" branch is large enough to serve as a primary feed to a zone valve station, sub-distribution header, pump inlet, or filtration system inlet, yet represents a meaningful size step down from the 8" main that makes this fitting suitable for a broader range of branch applications than the near-full-bore 8"x6" reducing tee. This mid-range branch sizing makes the 401-582 one of the most commonly specified configurations in large-diameter PVC reducing tee applications — versatile enough to appear in municipal water distribution, large-scale irrigation, industrial process piping, and commercial plumbing systems where 4" is the standard branch size for zone feeds, service connections, and equipment inlets off an 8" main.

The single-component approach integrates the branch reduction directly into the fitting body rather than introducing it as a separate downstream constriction, producing a cleaner hydraulic profile at the branch junction and a more compact installation footprint than a two-fitting assembly. Manufactured from white PVC compound meeting ASTM D2466 dimensional standards, the 401-582 delivers the corrosion resistance, chemical inertness, and long-term durability expected from Schedule 40 PVC in large-bore water distribution, irrigation infrastructure, and industrial process piping applications at this diameter and pressure class.

Specifications:

Heavy-bodied solvent cement is required for all socket joints at 4" and above. Allow full extended cure time before pressurizing or backfilling — 8" socket joints require significantly longer cure schedules than small-bore fittings; the 4" branch socket cure time should be observed independently as well. Thrust restraint or thrust blocking should be evaluated at branch tee locations in pressurized buried systems. Pressure-temperature derating applies at elevated service temperatures per ASTM standards.

Industries & Applications:

• Municipal Water Distribution — Transmission and primary distribution mains requiring a 4" branch feed to service zone sub-mains, fire hydrant laterals, booster station inlets, storage tank fill connections, or pressure zone boundary valves where a single reducing tee eliminates a downstream reducer and consolidates the branch junction into one fitting
• Agricultural & Large-Scale Irrigation — 8" mainline trunk distribution with a 4" branch drop to zone valve stations, pump bypass connections, filter manifold inlets, fertigation system feeds, or sub-main headers on large farms, golf courses, and managed landscape campuses where 4" is the standard branch size for primary zone distribution off an 8" trunk
• Industrial Process Piping — High-volume fluid transfer headers requiring a 4" branch takeoff to a secondary process loop, equipment inlet, parallel cooling circuit, chemical dosing header, or large-capacity secondary distribution line where the 4" branch carries a meaningful share of the process flow volume
• Water & Wastewater Treatment — Plant distribution mains supplying 4" branch feeds to filtration train inlets, aeration distribution headers, clarifier influent connections, chemical feed manifolds, or secondary treatment process lines where Schedule 40 construction meets the pressure and service requirements
• Stormwater & Flood Control Infrastructure — Large-diameter gravity or low-pressure stormwater collection and conveyance systems requiring a 4" branch junction off an 8" trunk main at lateral connections, basin inlets, or below-grade routing transitions
• Fire Protection Supply Systems — Underground or above-grade 8" fire suppression supply mains with a 4" branch feed to hydrant laterals, sprinkler system risers, standpipe supply connections, or dedicated suppression loop feeds requiring a serviceable branch size for fire flow demands
• Commercial & Institutional Plumbing — High-capacity chilled water, condenser water, or domestic water mains with a 4" branch drop to mechanical room equipment, heat exchanger connections, large fixture groups, or parallel distribution circuits in commercial building or campus utility systems
• Aquaculture & Water Management — High-flow recirculation, intake, or discharge headers requiring a 4" branch takeoff to parallel raceways, pond inlet manifolds, treatment system feeds, or secondary distribution circuits where 4" branch capacity matches the secondary flow requirements of the system layout