Along with elbows, carbon steel pipe fittings also consist of tees, which connect 3 areas of pipe, developing junctions for fluid circulation. Equal tees are used when the linking branches are of the very same size, while reducing tees are employed when the branch pipe is of a smaller size. https://sciencewiki.science/wiki/Utilizing_Equal_and_Reducing_Tees_for_Optimal_Fluid_Distribution