API Std 650 - Roof Manholes (in)

API Std 650 - Roof Manholes (in)

• [a] Pipe may be used for neck, providing the minimum nominal wall thickness is 1/4 in.  (ID and D_P shall be adjusted accordingly.)

Size of Manhole

(NPS)

Diameter of Neck [a], ID

In

Diameter of Cover Plate, D_C

In

Diameter of Bolt Circle

In

Number of Bolts, D_B

In

Diameter of Gasket Inside

In

Diameter of Gasket Outside

In

Diameter of Hole in Roof Plate or Reinforcing Plate, D_B

In

Outside of Diameter of Reinforcing Plate, D_R

In