Reducer fittings, bronze threaded (left) and copper sweat (right)
A reducer is the component in a pipeline that reduces the pipe size from a larger to a smaller bore (inner diameter).
The length of the reduction is usually equal to the average of the larger and smaller pipe diameters. There are two main types of reducer: concentric and eccentric reducers.
A reducer can be used either as nozzle or as diffuser depending on the mach number of the flow.
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