New to this forum and this seemed like the best choice to ask my question related to P&ID's. What is the normal convention for showing/labeling nozzle tags for equipment like tanks and pressure vessels ? In other words are the N1, N2, N3, etc. tags typically placed on the P&ID ? I have seen P&ID's on various projects done with & without nozzle tags indicated. Just trying to get a general opinion from other pipers.

Certain tagging is considered mandatory for a P&ID; primarily these are line numbers, instrument numbers, equipment numbers and specialty items. The inclusion of other tagging, such as manual valves codes and nozzle numbering, varies according to the company standards. Personally I consider nozzle numbers on P&IDs as mandatory because they are a necessary reference back to the vendor drawings for so many people: process and mechanical engineering, the designer, the checker, and construction and start-up teams. If they are not included then everyone concerned with the nozzle numbering will have to mark them on their own set of P&IDs for themselves, which will lead to extra work and possibly confusion and additional questions.

As per me,
Nozzle tags on the PID helps a lot to avoid confusions & Nozzle tags are must on the PID. But however I have seen many projects where nozzle tags are not shown on PIDs which created so much of confusion everytime.

Could anybody tell us why this problem exisits?? Why process do not show the Nozzle Tags?? Is it because lack of Information to them?? or aything else??

Pls revert to know it better....

Thanks to each of you for your input. I totally agree with both of you, nozzle tags on the P&ID eliminate alot of confusion and possible errors later in a project. Trying to convince some of the engineering personnel on a current job that this is needed and wanted to get some input.

Ask them if they think it's better for the field construction, and later operations and maintenance, to have all the information in front of them and to be able to cross-reference easily between P&IDs, piping drawings and vendor drawings, or have to sit with the piping drawings, vendor drawings and a set of P&IDs and identify the nozzle tags for themselves. Keep in mind that if the nozzle tags are not identified on the P&IDs as a permenent record, this same exercise will have to be conducted multiple times by different parties. It's a guarantee that someone will make a mistake at some point along the way, whereas it's a simple exercise to do it once and do it right in the engineering office for the benefit and convenience of all of the downstream people who will later rely on the accuracy of these drawings. Consider also that it is the job of an engineering company to anticipate the needs of the end users and to provide adequate information, not to turn out a product that requires further work later to fill-in the blanks.

This will also depend on the environment (kind of programme) being utilized. For e.g. if you are in SmartPlant Environment where SPPID and SP3D are correlated then all the attributes including the nozzle name need to match and then the items will turn green (indicating satisfactory match).

However, if the PIDs are drafted using 2D CAD software like ACAD then things have to be done manually. Nozzle naming certainly does help and may reduce your time little. But ultimately you do need to check and confirm this with Mechanical Data Sheet.

Process people, even if we hate them so much for changing data at the worst point of time, do follow certain drafting conventions in their schematic. Generally, the location of nozzle on PID equipment schematic is in good agreement with the location on MDS.