Look at UG-46 of the ASME Section VIII, Division 1 Code. If the User specifies "non-corrosive service" the vessel will probably not need an inspection opening. UG-46 covers all the requirements for inspections openings.
To drain out the condensate we can provide a drain valve at bottom centre.. but how could that affect provision for inspection opening ? as i understand inspection opening is to inspect the tank before installation and after fabrication.
and if user has not specified about corrosiveness of service medium and can manufacturer interpret service medium (instrument air, dew point temp. minus 40 Deg.C) as non-corrosive ?
details of the tank,
Volumes range from 20 Ltr to 1000 Ltr
Pressure : Max. 10 barg (instrument air)
Inside Diameter range from 220 mm to 1000 mm
Though user didn't explicitly specify the service as "non-corrosive", since the service medium being instrument air can we interpret that as "non-corrosive" ?
sekarjoy, you really need to read UG-46 carefuly. You will find that compressed air must be dried to a dewpoint of at least -46C to be exempted from UG-46 requirements.
You are probably talking about a couple of 3/4 NPT connections, which can maybe have other uses, to comply. Why not just do it?
You are going to at least need to get access to affected corrosive areas using atleast a borescope for inspection. Surely you can insert a borescope through the air inlet and outlet nozzles?
Sekar
Some clients are not directly specifying about corrosive service. In turn they are insisting to have some corrosion allowance during thickness calculation. Such equipment's have to be provided with inspection openings as per UG-46.