Inspection opeinings on 16 inch vessel

[MintJulep]

I'm looking a a drawing of a nominal 16-inch diameter pressure vessel alleged to be ASME Section VIII.

There are no inspection openings.

I recall that 16-inch is a "border" size, but I don't have ready access to our copy of the code.

Could someone refresh my memory.

Is a 16-inch vessel required to have inspection openings, or is it "...larger than 16 inches shall have openings..."

 

[MintJulep]

Memory is apparently fading.

12 thru 18 inch vessels require two 1-1/2" inspection openings.

 

[jte]

Mint-

Inspection openings are not required if the vessel is not subject to corrosion nor in compressed air service (UG-46). Having said that, it generally makes sense to provide some inspection openings. As you pointed out, a 16" ID vessel would require at least two 1½" NPS openings if inspection openings are required.

Often removable piping spools can be used to provide the necessary openings. If you can remove the inlet and outlet piping spools (or remove the vessel from the piping since it is relatively small), then this may be an option.

Of course, if you can use a 16" flange and blind flange instead of a head, or two 16" flanges as body flanges, that would make internal inspections much easier...

jt