Reinforcing of Opening in Roof Manway Cover Plate

[gdubyuh]

For an API-650 tank, designed to 0.3 psig internal pressure, a 24" roof manway exists with a 1/4" thick cover plate (as seen in Fig. 5-16 of API-650). Inserted into this cover plate, is an 8" (XS) vent nozzle. I cannot find in API-650 a section regarding 'reinforcing of opening in cover plates of roof manways'. Section 5.8.3.2 addresses 'reinforcing of openings in cover plates of shell manways'. Is 5.8.3.2 acceptable to apply to the reinforcing of the roof manway cover plate opening? Are the limits of reinforcment on the cover plate equal to a radius (above and below the centerline of the opening) of the diameter of the opening as 5.7.2.3 dictates for shell openings? How can it be determined how much of the 1/4" thick cover plate is excess thickness that can be applied as reinforcing? Thanks.

 

[rab1944]

It sounds like you have an Appendix F tank with the 0.3 psi design pressure. Apx. F will inturn direct you to API 620 for the design of the manways. Happy hunting.