Dimensions of Dished Ends for Pressure Vessels like Boiler, Reactor, Storage Tank

According to IS 4049 (Part-2): 1996 and Table 2 Dimensions for Dished and Flanged Ends (Torispherical)

• Inside Crown Radius is 80% of ID

• Inside knuckles Radius is 10% of ID and in no case less than 6% nor less than 3 x thickness of Dish.

•  Inside height of Dish can be calculated according to IS: 2825 – 1969 and IS 4049 (Part-2) : 1996 as follows:

• Now the Inside height can be calculated according to IS: 4179 – 1997 which is as follows: 

1. When Knuckle Radius is 10% of ID 

 

      2. When Knuckle Radius is 6% of ID

          Where h_i = Inside height of Dish

                      R_i = Crown Radius of Dish

                      r_i = Knuckle radius of Dish

                      D_i = Inside diameter of Dish 
                      S_f = Straight Flange length of Dish

•  Minimum length of straight flange shall be 3 x thickness of Dish or 20 mm but not exceed 38 mm except when necessary to provide required length of taper.