using colors in P&ID 1

[Pipeline1972]

Hello everyone.
We, here in the design office (piping design, chemical plant), are having a discussion about the use of colors in Piping & Instrumentation Diagrams. Some wants to use a different color, and layer, for each piping line (process, air, cooling water, raw water, nitrogen, steam, etc.. etc..). Others don't like this idea, saying you'll end up with a drawing in lots of different colors, and lots of layers, that colors are good for advertisement and marketing purposes. Adding a thickness to your line, depending on its use, (process primary, secundary, utility, instrumentation) makes more sense. Why use colors? To make it easier to read? Designers and Engineers working with P&ID should be able to read it, right? And besides, in all the documentation I'm reading, there's never a mention about the use of colors. But then again, things were different, in the ages before Autocad...

I would love to hear your opinions!
Thanks,and sorry if i posted this thread in the wrong forum! ;-)

Draftsman - Designer Industrial Piping

 

[thalon]

We use colour on our P&ID's and on our piping drawings. The benifits I see is that the colour makes it easier to follow the line on a P&ID, and allow you to have the information you want jump out at you. his is not to say that you can't follow a line on a P&ID with out colour, just that the colour make it a little easier.

On our piping drawings, the new piping is printed in blue (yellow on screen). Everything else in black. This little bit of colour make the new piping jump out at you muck more effectively the simply thickening a line.

You right in that more books don't talk about colour, as it is now much easier to produce colour drawing for a reasonable price.

I would pick you printed colours carefully. Yellow doesn't show up very well on white paper, and a dark blue doesn't show up well on the black screen in autocad (unless you have you settings to work on a white screen, too bright for my liking). As I mentioned above we have yellow lines on the screen that print blue.

 

[ctopher]

We use different colors and layers on everything. Our customers and vendors do the same. It is much easier to read and follow the dwg. If someone makes a dwg all one color, it is immediately changed.

Chris
Systems Analyst, I.S.
SolidWorks/PDMWorks 05
AutoCAD 05
ctopher's home site (updated 06-21-05)
FAQ559-1100
FAQ559-716

 

[zdas04]

Man, I wish you guys were preparing the P&ID's that I have to work from. Line weights would help, colors would help a lot. I always find myself falling off a process line onto a PSV vent and being confused.

David

 

[MikeHalloran]

Color, _alone_, should not be used as a differentiator, because:

- some people are colorblind
- faxes are monochrome
- colors fade with age





Mike Halloran
Pembroke Pines, FL, USA

 

[zdas04]

Mike,
I've heard all these points, but (1) 5% of the population is color blind (

http://waynesword.palomar.edu/colorbl1.htm),

a much smaller proportion of the population than stupid people and we try not to let them prevent change; (2) Faxes are also 8.5X11 or 8.5X14 and P&ID's are generally 11X17 or bigger--you have to do something special to ever fax a P&ID; (3) maybe, but I've not seen terrible fading in dark file cabnets.

On a P&ID with 5 or more systems, color might make the presentation worse, I don't know. Usually on a site that complex nothing but careful study will ever help me. Most of the P&ID's I see would be 3-4 colors and I think that color would help me a lot.

David

 

[IFRs]

The purpose of drawings is to communicate.
Anything that makes tbe communication more effective makes the drawing better.
Colors can be good but they can also be distracting.
Used with restraint and consistency, they can be great.

 

[Pipeline1972]

Yes, colors can be useful when used with restraint. It's all about finding the right balance.
I think putting the main line in a color is a good idea. And, in a project, the new lines.
But, as far as i could find, there is no "code" yet telling us to use colors, or not, right?
Here in the design office, we use 18(!) different colors and layers for *each* line! We seldom use them all in one drawing, but it could happen! Imagine such a drawing!

As for the faxes, I almost never fax anything anymore. I make a PDF of my drawing and email it to the client/contractor. Fast and convenient.


Draftsman - Designer Industrial Piping

 

[IFRs]

The ouly trouble I find with colors is with 3D objects. Some colors do not shade well in a pdf, depending on orientation. Some colors do not print well in black & white.

 

[zdas04]

3-D objects in a P&ID? I want to see your P&ID's instead of mine.

David

 

[CadDraftee]

As a person who has drafted P&IDs for 10 years I can see the benefits of colour, but a lot of work would be involved. particularly hard at the beginning of a project that is in a BFS or FEED stage, sometimes line specs and codes haven't even been set-up yet and who is to say they things may not even change once a detailed design starts. We have however created a separated set of P&ID's to use when commissioning comes around on the project and we then create individual colours of each of the systems and they do get some great feedback. This of course can't really be done until the design is finished as it would be to hard to maintain 2 sets of P&IDs - though we have had to do this in the past.

 

[pipingdesigner]

My $0.02 worth.
My preference, and the preference of many companies I have worked with is: (simple version)

* Process Lines, Utility lines, inst lines, elec lines, equip & text/attributes all have a layer each.

* Each of these layers have a seperate colour attached to them.

* Every colour has a coresponding line weight.

What these simple rues allow is:

* You can follow lines easily on screen.

* You can tell at a glance on screen if things are on the correct layer.

* Utility lines can print thinner than process lines yet thicker than inst lines - making black and white copies easy to follow - even when copies (xerox's) of the master drawing are made.

I don't hold with coloured drawings, because while the marketing guys love them, and they can look good for showing off you technological prowess to you clients, they are horrible to copy and process engineers and pipers can read a well proportioned P&ID in black and white.

and don't even get me started on P&IDs created using polylines with thickness .... arrghhhhh .....

pipingdesigner

http://www.pipingdesigners.com

 

[aardvarkdw]

I have never done much piping work and I work almost entirely in Inventor but when I do work in Autocad, I draw with every line type on a different layer and in a different color. This makes it easier for me to see what I am working with on the computer screen, and what I have on each layer. Then I set up my .ctb file to print using the line weights and types that I want for each layer. I also usually print in monochrome. This way I can tell what I am working on, but when I print the drawing it looks professional and is easy for anyone to read.

 

[11echo]

HOLD EVERTHING HERE FELLAS!!! ...Let the "old timer" put in his $0.02. ...Now I go back to the board days, where the only color you had to play with was blue! ...AND we got the job done every well Thank You! ...Now fast forward 30 yr.s ...YES you can make all the lines a different color and have all the layers set up to "standardize" the dwg, BUT all your doing is making things more complicated! You need to work under the K.I.S.S. principle (Keep It Simple Stupid)!!! All the colored cr*p is for the engineers ...not the poor guys that has to built it in the field. You ever Xerox a yellow line? OR any "colored" dwg? ...If you have you know WHY you don't do that! All you have to do is have thick or thin lines, the thick pop out at you in ANY dwg format (just like we did on the board days). The more "artsy/f*rtsy" you get with computer draws the harder is it to deal with down the road for the “other guy”. That may not float your boat but it's an economic reality in the real world. Remember, AutoCAD can have up to 255 layers, BUT THAT DOESN'T MEAN YOUR SUPPOSE TO USE EVERY ONE OF THEM!! …K.I.S.S …remember!?? ...The old guy.

 

[ctopher]

11echo,
I agree with you, to a point.
If you are working within the CAD file, separate colors are a must. The person that is using the files to build, will use a black/white dwg. Unless the builder is familiar with the software, the builder can use the file with different colors & layers. I would not send out a dwg that is viewing only with different colors, it is hard to read.

Chris
Systems Analyst, I.S.
SolidWorks/PDMWorks 05
AutoCAD 06
ctopher's home site (updated 06-21-05)
FAQ559-1100
FAQ559-716

 

[Ashereng]

Here are some of my ramblings.

At the last construction site I was at, we had a fax machine and a photocopier - both vintages of "old". We had a few stand alone computers, for reading word docs and excel and such.

A coloured P&ID (produced, not in AUTOCAD) would be problematic since the colours all go to grey scale by the time I get it.

Anyone who can't figure out the main process line, or follow the piping, shouldn't be responsible for building it. So no, it doesn't need to be in a different colour or thickness.

During the design and engineering stage, I agree, colour for new pipes, alternatives, on holds, etc. may be useful. Once it get to green field constructions - well, all the pipes are new. If it is work in an existing facility, there are other ways to idientify existing vs. new constructions other than colour.

There are colour blind people - though rare. More common are people who are colour pairs indifferent (can't tell the differenc between red/green, for example). I seem to meet more of those than people who are completely colour blind (only know of one who is complete colour blind).

Anyway, end of my ramblings. Thanks for putting up with it.

I guess colour is a good idea, like anything else, if used properly, in the right context, with the right support.

"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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