What type of fitting is required when reducing the pipe size on a horizontal steam pipe?

The use of an eccentric reducer is crucial when reducing the pipe size in a horizontal steam pipe because it allows for the maintenance of the centerline of the pipe. This is particularly important in horizontal installations where proper drainage and elimination of air pockets need to be managed effectively. An eccentric reducer is designed with a sloped end that keeps the same top or bottom level, helping to prevent the accumulation of condensate and ensuring that steam can flow freely without obstruction.

Additionally, this design helps facilitate a more uniform transition in pipe size, avoiding abrupt changes that could create turbulence or flow restrictions. In applications involving steam, maintaining the flow characteristics is essential for system efficiency and performance, which is effectively achieved through the use of an eccentric reducer rather than other fitting types that might not accommodate horizontal orientation or fluid dynamics correctly.