Manhole can be divided into several categories to introduce

1. Divided by manhole covering load capacity
According to the division of manhole coverage capacity, it can be divided into two types: steam-20 and steam-10.
2, divided by the direction of the manhole
    According to the direction of the manhole, it can be divided into straight manhole, three-way manhole, four-pass manhole, sanitary stainless steel manhole and oblique manhole, and the oblique manhole is divided into 15°, 30°, 45°. There are five kinds of 60° and 75°. The angle of each oblique manhole can be applied within ±7.5°.
3. Divided by communication pipe capacity
    According to the manhole, the pipe section pipe or the single hole pipe hole with a diameter of 360mm and a height of 250mm (standard six-hole pipe hole inner diameter 90mm cement pipe block, referred to as standard block) can be accommodated in the large and medium diameter. Small stainless steel manholes. The size of the manhole set in the communication pipe should be set in the forward capacity of the communication pipe. The capacity of building communication pipelines should not be considered only in this period.