Radiographic plugs and bosses

[jhambham]

I am working on a modification package for heavy wall pipe at one of our plants. Normally, when Radiograhpic Tests are performed, we shoot the RT with a source outside the pipe. Due to the location of this piping, we want to minimize the time that area is "closed" for the RT. To facilitate a speedier inspection, we will be installing RT inspection ports and will be installing radiographic plugs (straight thread)in accordance with PFI Standard ES-16. The standard tells me the distance from the welds and plugs sizes.

Here's my question: I cannot find any guidance in B31.1 or ASME Sect. III on position of the access holes. Can the access holes be located anywhere on the circumference of the pipe? Since the hole must be drilled and tapped, my first instinct is to place on the bottom of the piping to assure foreign material exclusion (drillings, shavings, etc from falling into the pipe). Is there any quidance documents?

Thanks for any help.
Jim Hamlin
jghamlin@southern.com

 

[pablo02]

I have only seen these taps either in the end (of a header), on the side, or on the top -- I would think that on the bottom is the least desireable place to put these -- allows a place for any foreign material to collect...

 

[deanc]

I am not aware of any Code requirements for location. ASME
SecV has some good info. for location of the source.

You may try pressurizing the line with low pressure air when you make the penetration. Proper eye protection of course.