Direct Answer
Pipe tees create branch connections in piping systems. An equal tee connects three pipes of the same size, while a reducing tee connects a smaller branch to a larger main pipe. Tees are used in oil and gas, chemical plants, water treatment, HVAC, power plants and industrial construction.
Tee Types
| Type | Description |
|---|---|
| Equal tee | All three outlets have the same nominal size |
| Reducing tee | Branch outlet is smaller than main pipe |
| Butt weld tee | Welded directly to pipe ends |
| Threaded tee | Threaded connection for smaller systems |
| Socket weld tee | Used in selected high-pressure small-bore piping |
Selection Factors
Important factors include material, pipe size, branch size, wall thickness, standard, pressure rating and connection type.
Common Materials
Carbon steel tees are common in general industrial piping. Stainless steel tees are used for corrosion-resistant or clean service. Alloy steel tees may be used for high-temperature or special service.
FAQ
What is a reducing tee?
A reducing tee has a branch connection smaller than the main pipe size.
What standard applies to butt weld tees?
ASME B16.9 is commonly used for factory-made butt welding tees.
Can tees be custom made?
Yes. Custom dimensions, wall thickness and material grades can be produced based on project drawings.
Related Product Page
For tee quotations, visit PipingFitting.com.
Equal Tee vs Reducing Tee
An equal (straight) tee has all three outlets the same size – 4″x4″x4″ – used when the branch carries the same flow class as the run. A reducing tee has a smaller branch – 6″x6″x4″ – letting one fitting do a branch and a size change. Reducing tees save a weld and a fitting wherever the branch is smaller than the run; they are ordered as “run x run x branch”.
Tee Dimensions & Schedules
Per ASME B16.9, the run length (C) of a tee is about twice the NPS (a 4″ tee: C=4.5″), and the outlet length (M) scales with branch size. Walls follow the pipe schedule – SCH10 to SCH160 – and the crotch area is inherently reinforced by the fitting’s geometry, which is why a true tee outperforms an unreinforced welded branch at the same wall. For branch sizes below half the run, compare the tee price against a run tee alternative or branch outlet fitting.
Ordering & FAQ
State: run size x branch size, schedule, material (A234 WPB / A403 WP304L / WP316L), standard (B16.9 / GB/T 12459), and documentation level. FAQ: which outlet orientation do tees come in? Straight tees branch perpendicular to the run; “laterals” (Y-tees) branch at 45° – a separate B16.9 category for merging flows gently. Request tee pricing.