Deciding between Minor & Major Process Lines

[HybridAWD]

For those who use the AutoPLANT P&ID, what is your procedure on determining whether or not a line is a major process line or a minor process line?

Now, my answer would be, whatever is not to be piped (small bore) 3" and below shall be minor line and not require a line number. However, there are exceptions with some sample drains.

I'm just looking for input on how others decide between the two. Thanks

[Data Wrangler]

You could do it based on pipe size, or you could do it based on order of importance; i.e. my main process line is major, but all other supporting lines (instrument air, process water, etc.) are minor.

I don't think there are any hard and fast rules here...

Derek

[Aplant Monkey]

I don't believe there is an easy answer to this. I have experienced several philosophies.Some would agree with you in terms of what the scope of the project is. problem is when you get to detailed design everything needs to be piped. Another is that if it is a utility rather than a process line it would me a minor line, this works fine till you get to Utility PID's then everything is a major. What about a 24" steam line. I would have to say that a 24" line is pretty major regardless of what the commodity is inside. My expereince is that as long as you outline in advance what is it going to be then everyone is happy. My personal favorite is anything below 2" is minor anything above is Major, simple and to the point. Lots of poeple have an opinion on this one though and like I said there can be No easy answer to this as there is an arguement against just about every situation

[vishalra]

Just to add one more point of view, in autoplant choosing the major or minor would help you classifying them later if you wish to do so using the datamanager.