Bullhead Tee, Slip x Slip x Slip PVC Schedule 40 6" x 6" x 8" (401-535)

The 6" x 6" x 8" PVC Schedule 40 Bullhead Tee (Slip x Slip x Slip), Part #401-535, is a purpose-built large-branch tee fitting that inverts the conventional tee geometry — the 8-inch branch outlet is larger than the 6-inch run ports, rather than smaller. Manufactured from Type I, Grade I PVC compound to ASTM D2466 specifications, this fitting delivers reliable pressure performance, broad chemical resistance, and long service life in the specialized flow collection, manifold, and header applications where bullhead tee geometry is the correct engineering solution.

The bullhead tee configuration is a critical and frequently misunderstood fitting type. In a standard reducing tee, flow moves primarily along the run and a portion branches off through a smaller outlet. In a bullhead tee, the relationship is reversed: two incoming flows from the run ports are collected and discharged through a larger branch outlet, or a single upstream flow is split and distributed through two smaller run outlets while the larger branch serves as the primary supply or discharge point. This geometry is encountered in applications where the branch carries the dominant flow — not the run — making a standard tee or reducing tee geometrically and hydraulically unsuitable.

The most common use case for a bullhead tee at this size is pump suction manifold and collection header design, where multiple smaller supply lines feed into a common larger-diameter discharge or suction port. The 6-inch run ports collect flow from two branch circuits while the 8-inch outlet delivers the combined volume to a pump suction, filter inlet, or primary distribution main — a configuration that would require a fabricated or custom assembly without a purpose-manufactured bullhead tee. Similarly, in reverse-flow systems, the 8-inch inlet can supply two 6-inch distribution branches simultaneously from a single larger-diameter feed.

The slip x slip x slip (plain end) configuration accepts solvent cement across all three ports, producing permanent, chemically bonded joints at the run and branch connections. As with all non-standard tee geometries, installation orientation relative to flow direction matters — the bullhead tee should be oriented so that the larger branch port aligns with the dominant flow direction in the system, with hydraulic design accounting for the velocity and pressure changes inherent in the size differential between run and branch.

Specifications:

Note: Pressure rating decreases with elevated temperatures and is further influenced by dynamic flow conditions at the branch junction. The bullhead tee geometry — where branch diameter exceeds run diameter — introduces flow dynamics that differ meaningfully from standard tee configurations, including higher turbulence at the branch junction, potential recirculation zones, and elevated head loss compared to standard reducing tees of equivalent size. These factors should be accounted for in hydraulic design, pump sizing, and system pressure calculations. Consult ASTM D2466 derating curves and applicable engineering specifications before installation in high-pressure, high-velocity, or continuously pressurized service.

Industries & Applications:

• Pump Suction Manifolds — Collecting flow from two 6-inch supply lines into a single 8-inch pump suction port — one of the most common and purpose-built applications for bullhead tee geometry, where the larger branch serves as the suction connection and the run ports aggregate flow from upstream supply circuits or storage.
• Irrigation & Agricultural Systems — Header and manifold assemblies on large-scale irrigation systems where two 6-inch zone or sector supply lines must combine into a single 8-inch mainline feed, pump suction, or filter inlet — particularly at pump station manifolds, booster pump suction headers, and filtration system inlets.
• Municipal Water Distribution — Collection manifolds and header assemblies in water utility infrastructure where two smaller branch feeds must be aggregated into a larger primary main or pump suction connection, and standard tee geometry does not accommodate the required flow direction and size relationship.
• Industrial Process Piping — Flow collection and aggregation in chemical processing, manufacturing, and plant utility systems where multiple mid-size process lines converge into a larger primary circuit, discharge header, or equipment connection requiring the bullhead configuration.
• Water & Wastewater Treatment Plants — Process manifolds, filter influent and effluent headers, and recirculation system assemblies where collecting flow from multiple mid-size lines into a larger-diameter process connection is a recurring design requirement.
• Aquaculture & Recirculating Systems — Recirculating aquaculture system (RAS) manifolds where flow from multiple tank drain or return lines must be collected into a larger common discharge or filtration inlet, making bullhead geometry a practical solution for compact manifold design.
• HVAC & Mechanical Systems — Chilled water and condenser water system headers in large commercial and industrial facilities where two 6-inch branch circuits must combine into an 8-inch primary distribution main or equipment connection at a manifold assembly.
• Fire Suppression & Water Storage Systems — Supply manifolds and tank outlet assemblies where multiple smaller supply lines aggregate into a larger primary feed for fire pump suction, gravity flow systems, or booster pump stations.