What is typically reduced in a reducing elbow?

In a reducing elbow, the primary function is to connect two pipes of different diameters, thus the pipe diameter is indeed reduced. These fittings are designed to enable a smooth transition from a larger diameter pipe to a smaller one, allowing the system to effectively handle changes in flow direction while accommodating the difference in size.

The reduction in pipe diameter is essential in applications where it's necessary to maintain pressure or increase velocity as the fluid moves from a larger pipe to a smaller one. This design reduces turbulence and helps maintain a steady flow of the fluid being transported. The process also impacts other factors, such as flow capacity and pressure, but the main attribute of a reducing elbow is its role in changing the diameter of pipes rather than altering flow capacity or temperature directly.