Regarding the issue of the size ratio of the gauge legend circles in PID
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Gentlemen, as a beginner in PID control, I naturally face numerous difficulties. I’d like to ask everyone for help with one question first. Regarding the issue of the size ratio of the circles in the gauge legends within the PID, the specifications require that the diameter of these legend circles be 10 mm. Is such a size too small for the entire drawing? Is it necessary to set the drawing scale? If so, how to set it? Thank you all for your guidance!
This size is sufficient; it allows for clear viewing.
When drawing piping diagrams at a 1:1 scale, the equipment and pipes are all several dozen meters long, which results in the diagram legends being clearly out of proportion!
No scale is used in the PID diagram. Just indicate how large the image needs to be.
So this is my question: with a 10mm gauge legend, on a pipeline diagram that is over ten meters long, will it not be visible?
It is sufficient as long as it is clear when the image is produced; generally, 8-10 mm is appropriate
What kind of picture are you talking about? As mentioned upstairs, PID doesn’t include a proportional element, and the pipes shown there are merely illustrative. When you say that the pipes in the equipment are all over ten meters long, it seems like you’re not referring to PID but rather to piping diagrams
On an A1 sheet, when the measurements are printed at 10mm, they remain quite clear. Normally, when we create drawings in A1 format and output them in A3 size, they are still very readable.
Sir, when there’s no scale involved, you can draw the pipes as long as you like – as long as they’re visible enough. This doesn’t conflict with using 10mm to represent the diameter of the gauge
The PID diagram does not need to be drawn to scale; the instrument symbols in the software are already defined, so they can be used directly. For the layout of PID diagrams, it’s sufficient to make the devices appear relatively large or relatively small; for example, a pump should not be drawn larger than a storage tank.
In PID flow diagrams, pipelines and equipment do not need to be drawn to scale; clarity is sufficient. However, valve arrows and instruments must be drawn in accordance with standard requirements