How to understand P&ID diagrams
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At my company, I am mainly responsible for equipment design; occasionally I have the opportunity to work with process systems. I can generally understand the PFD diagrams that my colleagues in process design provide, but P&ID diagrams confuse me greatly. The instrument symbols such as PIA, PIT, PSV, PCV, FIA, PS, and PSA are completely unintelligible to me, and all the various interlocks and auxiliary pipelines are also mixed together. . . I would like to ask the experts: how can one understand P&ID diagrams more thoroughly? What materials need to be consulted?
Without years of experience, it’s not that easy to understand, especially self-control interlocks
First, understand the image on the home page (the legend); these symbols are explained in the image on the home page.
First, you must understand the legend; secondly, you need to be familiar with the process flow. It’s not necessary to be expert in it, but at least a basic level of familiarity is required, otherwise it will only get more confusing the more you look at it!
I suddenly discovered a serious problem. . . So P&IDs do have legends? I didn’t get one. . . Just a pair of gauge symbols on one diagram. I’m stunned; they’re all sent by foreigners – it’s completely unreliable
The process flow seems to be fine; our process for hydrogen chloride desorption is also relatively simple. The problem seems to lie in the legend; the company’s P&ID diagrams don’t even have a legend. . .
Well, now I have a clear understanding. First, I need to grasp the process flow, then understand the abbreviations for instruments and valves, and finally figure out the automatic control interlocks
With a certain foundation and an understanding of the process, it’s not difficult when using the PID legend.
There are pictures for explanation; read the instructions first. If not, I would look it up online one by one or ask my colleagues; after understanding each one, things seemed much clearer. For example, PS generally refers to a pressure switch, where P means pressure.
There are many gauge symbols, and it is necessary to first understand their meanings.
Find a legend; each letter represents a different meaning in various positions. First, memorize the more common ones, and then those that are less common. It shouldn’t be difficult for you to understand these on your gauge, right? Remember it slowly