Stainless steel tee pipe fittings are pipe fittings used to change the flow direction of fluid in a pipeline or to realize pipeline branching. They play an important connecting role in the pipeline system. It has three interfaces, usually in a "T" or "Y" shape. The main pipe and branch pipe of the "T" shaped tee pipe fitting intersect at right angles, while the main pipe and branch pipe of the "Y" shaped tee pipe fitting are at an acute angle.

• Butt-welded tee: A stainless steel tee pipe fitting that is welded after docking with the connecting pipe fitting.
• Socket tee: A tee pipe fitting that is welded or fused after the connecting pipe fitting is inserted into each end of the tee.
• Compression tee: A tee pipe fitting with compression fittings at each end, which is tightened after the pipe fitting is inserted.
• Threaded tee: A tee pipe fitting that connects pipe fittings in a threaded manner.

According to the material classification, it can be divided into stainless steel tee, carbon steel tee, copper tee, PVC tee, ductile iron tee, etc.

• Carbon Steel: ASTM A105, 20#, Q235, 16Mn, ASTM A350 LF1, LF2 CL1/CL2, LF3 CL1/CL2, ASTM A694 F42, F46, F48, F50, F52, F56, F60, F65, F70, etc.
• Alloy Steel: ASTM A182 F1, F5a, F9, F11, F12, F22, F91, A182F12, A182F11, 16MnR, Cr5Mo, 12Cr1MoV, 15CrMo, 12Cr2Mo1, A335P22, St45.8/Ⅲ, 35CrMoV, 45CrMo, etc.
• Stainless Steel: ASTM A182 F304, 304L, F316, 316L, 1Cr18Ni9Ti, 0Cr18Ni9Ti, 321, 18-8, etc.

• Straight tee: A tee pipe fitting with a branch pipe perpendicular to the main pipe.
• Oblique tee: A tee pipe fitting with a certain angle between the branch pipe and the main pipe.

Casting stainless steel tee pipe fittings involves pouring molten stainless steel liquid into a pre-made tee-shaped mold and waiting for it to cool and solidify to obtain a tee pipe fitting. The casting process can produce tee pipe fittings with complex shapes. For some specially designed tee structures, the casting process has more advantages. However, defects such as pores and shrinkage may occur during the casting process, and strict quality control measures are required to ensure the quality of the stainless steel tee pipe fittings. For example, the use of precision casting technology can improve the dimensional accuracy and surface quality of the pipe fittings and reduce the occurrence of defects.

When the welding process is used to make stainless steel tee pipe fittings, the cut stainless steel plates or pipes are usually welded and assembled according to the shape of the tee. First of all, it is necessary to ensure that the welding material matches the parent material (the stainless steel material being welded) to ensure the welding quality. During the welding process, it is necessary to control the welding parameters, such as welding current, voltage, welding speed, etc. The welded three-way pipe fittings need to be subjected to non-destructive testing (such as X-ray flaw detection, ultrasonic testing, etc.) to detect whether there are defects in the weld, such as pores, slag inclusions, and incomplete penetration. The welding process has high production efficiency and is suitable for mass production, but the performance of the welded part may be different from that of the parent material, and appropriate subsequent treatment such as heat treatment is required to improve it.