Feeding long and short fiber switching pipeline of pulping machine

The utility model discloses a feeding long and short fiber switching pipeline of a pulping machine. The feeding long and short fiber switching pipeline comprises a short fiber grinding forebay and a long fiber grinding forebay, the short fiber mill forebay and the long fiber mill forebay are respectively connected to an inlet of the pulping machine through a gate valve and a material pump; an outlet of the pulping machine is respectively connected with the first butterfly valve and the second butterfly valve; the first butterfly valve is connected to the short fiber grinding rear tank; the second butterfly valve is respectively connected with a long fiber tank flowmeter and a backflow tank flowmeter; the long fiber tank flowmeter and the reflux tank flowmeter are connected to the long fiber mill rear tank and the long fiber mill front tank; a first pneumatic control valve is arranged between the long fiber pool flow meter and the long fiber after-grinding pool; and a second pneumatic control valve is arranged