On August 28, 2025, one of our long-standing domestic clients placed another urgent order for three ASME B16.9 butt weld tees. The material specified was 316L. During communication, the client expressed their hope that we could deliver the products as quickly as possible to address the critical needs of their current project.
Fortunately, our factory had existing stock available. We immediately organized the production and shipping process. Despite the extremely tight deadline, we steadfastly upheld our principle of quality first. Before delivering the products that same day, we conducted rigorous inspections on every tee. The shipment was successfully dispatched that day, and the client expressed high recognition for our rapid response and high-quality inspection standards.
This order not only demonstrates our efficient delivery capabilities but also showcases our commitment to maintaining quality control even under urgent circumstances. No matter how pressing the client’s needs, we consistently ensure every product meets standards and client expectations.
We can not only produce standard tees, but also customize flanged tee. If you want to know more, please click
Butt Weld Tee Dimensions Inspection
Port Diameter: Measure the inner and outer diameters of the main pipe and branch pipes to ensure compliance with design specifications.
Wall Thickness: Inspect pipe wall thickness using calipers or ultrasonic thickness gauges to guarantee pressure resistance meets standard requirements.
Total Fitting Length: Measure the total length of the main pipe and branch pipes to ensure proper alignment during on-site installation.
Branch Angle: Measure the connection angle between the branch pipe and main pipe (typically 45°, 90°, or custom angles) to ensure correct fluid flow direction.
Specification of ASME B16.9 Tee
| Shape Type | Equal Tee and Reducing Tee |
| Size Range | 1/2″ – 80″ / DN15 – 2000 |
| Thickness Schedule | SCH 10 – SCH 160, XXS |
| Standard | GB/T12459, GB/T13401, HG/T21635/21631, SH3408/3409， ANSI / ASME B16.9, MSS SP 43, JIS B2311/2312/2313, DIN2605/2615/2616/2617, EN10253 |
| Carbon Steel | Q235, 20#, 35#, 45#, 20G,Q345B, 16Mn, ASTM A234 WPB/WPC, A420 WPL6 |
| API 5L Grades | ASTM A860 WPHY 42 / 46 / 56 / 60 / 65 |
| Alloy Steel | ASTM A234 WP11 / WP12 / WP 5 / WP9 / WP91 / WP92,15CrMoG, 12Cr1MoVG, 12Cr5Mo, 1Cr5Mo, Cr9Mo, 10CrMo910, 12CrMo4-5 |
| Stainless Steel | ASTM A403 WP304/304L/304H, 316/316L, 310S, 317,347, 904L, A815 S32205, S31803, 32750, 32760 |
ASME B16.9 Specification for Butt Welded Fittings
This Standard covers overall dimensions, tolerances, ratings, testing, and markings for factory-made wrought buttwelding fittings in sizes NPS 1/2 through NPS 48 (DN 15 through DN 1200).
Codes and Regulations.
A fitting used under the jurisdiction of the ASME Boiler and Pressure Vessel Code(BPVC), the ASME Code for Pressure Piping, or a governmental regulation is subject to any limitation of that code or regulation. This includes any maximum temperature limitation or rule governing the use of a material at low temperature.
Pressure Rating Designation
Class followed by a dimensionless number is the designation for pressure-temperature ratings. Standardized designations for flanges per ASME B16.5 referenced in this Standard are Classes 150, 300, 600, 900, 1500, and 2500.
Marking
Standard Marking Each fitting shall be permanently marked to show the following:
(a) manufacturer’s name or trademark
(b) material identification, either the ASTM or ASME grade designation
(c) schedule number1 or nominal wall thickness in mm
(d) size — the nominal pipe size (NPS) identification number related to the end connections shall be used
(e) compliance—see para. 4.4 for standard and special fitting marking
A manufacturer may supplement these mandatory markings with others, including a DN size designation, but confusion with the required marking shall be avoided.
ASME B16.9 Butt Weld Equal Tee
Equal Tee: All three ports have the same nominal diameter, meaning the main pipe and branch pipes have the same diameter. It is suitable for situations where the flow rates of the main pipe and branch pipes are the same, ensuring relatively balanced fluid velocity across all pipes. It is commonly used in piping systems requiring symmetrical branching, such as certain symmetrically arranged equipment connection pipes.
ASME B16.9 Butt Weld Reducing Tee
Reducing Tee: The nominal diameters of the three ports are different, typically with the main pipe having a larger diameter than the branch pipes. This type of tee is suitable for pipeline systems where both branching and merging occur, while also requiring changes in pipe diameter. It allows flexible adjustment of pipe diameter based on different flow requirements and is widely used in pipeline systems such as oil and natural gas transportation.
SS Butt weld Tee Material
Chemical Composition of ASTM A403 Buttweld Equal Tee
| CHEMICAL | LIMITS | C | Mn | P | S | Si | Ni | Cr | Mo |
| ASTM A403 WP304 | MIN | 8.0 | 18.0 | ||||||
| MAX | 0.08 | 2.00 | 0.045 | 0.030 | 1.00 | 11.0 | 20.0 | ||
| ASTM A403 WP316 | MIN | 10.0 | 16.0 | 2.00 | |||||
| MAX | 0.08 | 2.00 | 0.045 | 0.030 | 1.00 | 14.0 | 18.0 | 3.00 |
Mechanical Properties of ASTM A403 Buttweld Reducing Tee
| MATERIAL | ASTM A403 WP304 | ASTM A403 WP316 |
| T.S (MPA) | 515 min | 515 min |
| Y.S (MPA) | 205 min | 205 min |
| EL % | 28 min | 28 min |
Dimension of ASME B16.9 Tee
| NPS | O.D. | Center to End | Center to End |
| D | C | M | |
| 1/2 | 21.3 | 25 | 25 |
| 3/4 | 26.7 | 29 | 29 |
| 1 | 33.4 | 38 | 38 |
| 1.1/4 | 42.2 | 48 | 48 |
| 1.1/2 | 48.3 | 57 | 57 |
| 2 | 60.3 | 64 | 64 |
| 2.1/2 | 73 | 76 | 76 |
| 3 | 88.9 | 86 | 86 |
| 3.1/2 | 101.6 | 95 | 95 |
| 4 | 114.3 | 105 | 105 |
| 5 | 141.3 | 124 | 124 |
| 6 | 168.3 | 143 | 143 |
| 8 | 219.1 | 178 | 178 |
| 10 | 273 | 216 | 216 |
| 12 | 323.8 | 254 | 254 |
| 14 | 355.6 | 279 | 279 |
| 16 | 406.4 | 305 | 305 |
| 18 | 457 | 343 | 343 |
| 20 | 508 | 381 | 381 |
| 22 | 559 | 419 | 419 |
| 24 | 610 | 432 | 432 |
| 26 | 660 | 495 | 495 |
| 28 | 711 | 521 | 521 |
| 30 | 762 | 559 | 559 |
| 32 | 813 | 597 | 597 |
| 34 | 864 | 635 | 635 |
| 36 | 914 | 673 | 673 |
| 38 | 965 | 711 | 711 |
| 40 | 1016 | 749 | 749 |
| 42 | 1067 | 762 | 711 |
| 44 | 1118 | 813 | 762 |
| 46 | 1168 | 851 | 800 |
| 48 | 1219 | 889 | 838 |
Applications of Stainless Steel Butt Weld Tee
Petroleum and Natural Gas Industry
Chemical Industry
Food and Pharmaceutical Industry
Power and Energy Industry
Shipbuilding and Marine Engineering
ANSI/ASME B16.9 Buttweld Equal Tee Manufacturer
We are a professional butt weld tee manufacturer equipped with comprehensive production facilities and a rigorous quality management system. Our product range encompasses carbon steel, stainless steel, and alloy steel materials, compliant with international standards such as ASME, DIN, EN, and GB. Whether it’s equal-diameter, reducer, or slant tees, we offer multiple size specifications to meet diverse operational requirements across industries including petroleum, chemical, power generation, and seawater treatment.
Throughout production, we emphasize quality control at every stage—including dimensional inspection, material composition analysis, and weld seam examination—ensuring each product delivers consistent reliability in service. With efficient delivery capabilities and stable product quality, we have established long-term partnerships with numerous domestic and international clients, positioning us as a trusted supplier of pipeline fittings.
If you are seeking a professional and reliable supplier of butt weld tees, please feel free to contact us anytime. We are committed to providing you with premium products and comprehensive services.