Butt Weld Tees (Equal & Reducing)
Giriraj Impex is a manufacturer, stockist, supplier and exporter of butt-weld pipe tees – equal tees, reducing tees and barred tees – to ASME B16.9 and MSS SP-43. We manufacture pipe tees in stainless steel, carbon steel, alloy steel, duplex and super duplex steel and nickel alloys, seamless and welded, from ½" to 48" NB, in schedules from Sch 5S to XXS, with mill test certificates.
A tee creates a 90° branch from a run pipe, splitting or combining flow. Tees are used in every process, utility and pipeline system.
Types of tees
- Equal (straight) tees – branch the same size as the run.
- Reducing tees – branch smaller than the run, in standard size combinations to ASME B16.9.
- Barred tees – with bars across the branch to stop pipeline pigs entering, for piggable lines.
- Crosses – two branches opposite each other, used where four lines meet.
For small branches from large run pipes, olets are often used instead of reducing tees – see olets.
Specifications
| Item | Details |
|---|---|
| Dimensional standards | ASME B16.9, MSS SP-43 (light wall), MSS SP-75 |
| Sizes | ½" to 24" NB seamless; up to 48" NB welded |
| Schedules | Sch 5S, 10S, 40S, 80S, 10 to 160, STD, XS, XXS |
| Construction | Seamless or welded |
| Ends | Bevelled to ASME B16.25 |
| Documents | Mill test certificate (MTC); third-party inspection on request |
Equal tee dimensions
| NPS | OD at bevel | Centre to end – run (C) | Centre to end – outlet (M) |
|---|---|---|---|
| ½ | 21.3 | 25 | 25 |
| ¾ | 26.7 | 29 | 29 |
| 1 | 33.4 | 38 | 38 |
| 1¼ | 42.2 | 48 | 48 |
| 1½ | 48.3 | 57 | 57 |
| 2 | 60.3 | 64 | 64 |
| 2½ | 73.0 | 76 | 76 |
| 3 | 88.9 | 86 | 86 |
| 4 | 114.3 | 105 | 105 |
| 5 | 141.3 | 124 | 124 |
| 6 | 168.3 | 143 | 143 |
| 8 | 219.1 | 178 | 178 |
| 10 | 273.1 | 216 | 216 |
| 12 | 323.9 | 254 | 254 |
| 14 | 355.6 | 279 | 279 |
| 16 | 406.4 | 305 | 305 |
| 18 | 457.0 | 343 | 343 |
| 20 | 508.0 | 381 | 381 |
| 24 | 610.0 | 432 | 432 |
For reducing tees, the run dimension (C) is the same as for the equal tee of the run size, and the outlet dimension (M) is given in ASME B16.9 for each branch size.
Dimensions are from ASME B16.9 and are given for guidance; always check the current edition and the project specification. More fitting dimensions are in the butt-weld fitting dimensions chart.
Tee materials
- Stainless steel pipe fittings – ASTM A403 WP304/304L, WP316/316L, WP321, WP347.
- Carbon steel pipe fittings – ASTM A234 WPB, WPC; A420 WPL6; MSS SP-75 WPHY.
- Alloy steel pipe fittings – ASTM A234 WP5, WP9, WP11, WP22, WP91.
- Duplex steel pipe fittings – ASTM A815 WPS31803, WPS32205.
- Super duplex pipe fittings – ASTM A815 WPS32750, WPS32760.
- Inconel pipe fittings – ASTM B366, and other nickel alloys.
All fitting materials are on the pipe fittings page.
How we manufacture tees
Seamless tees are made from pipe by hydraulic bulging, where a section of pipe is held in a die and internal pressure pushes metal out to form the branch, or by hot extrusion, where the branch is drawn out from a hole in the heated pipe. Large tees are fabricated from plate or pipe and welded. The crotch – where branch meets run – is the most highly stressed area, so wall thickness there is controlled closely. After forming, tees are heat treated as required, machined to bevel ends and checked for dimensions. Each tee is marked with material, size, schedule and heat number.
Tees or olets?
Tees are used when the branch is the same size as the run or one or two sizes smaller, and when flow conditions favour a smooth, full-strength branch. For small branches from large pipes, such as instrument, vent and drain connections, olets are cheaper and lighter. The piping specification's branch table sets which to use for each size combination.
Where a branch carries flow at high velocity into or out of the run, a tee also gives a smoother flow pattern than an olet, which reduces erosion and vibration.
Ordering tees
Please give the material, type (equal, reducing or barred), run and branch sizes, schedule, seamless or welded construction, quantity and any testing or inspection requirement.
Frequently Asked Questions
An equal tee has a branch the same size as the run; a reducing tee has a smaller branch.
Under ASME B16.9, a 4" equal tee has a centre-to-end dimension of 105 mm on both run and outlet.
A barred tee has bars across the branch opening to stop pipeline pigs from entering the branch.
By hydraulic bulging or hot extrusion of pipe, followed by heat treatment, machining and inspection.
Olets are used for small branches from large run pipes, as set by the branch table in the piping specification.
ASME B16.9 covers butt-weld tees, with MSS SP-43 for light-wall stainless tees.
Request a Quote for Butt Weld Tees (Equal & Reducing)
Tell us the product, grade, size, standard, quantity and delivery location, and our sales team will reply with a quotation.
Inconel® is a trademark of Special Metals Corporation.