P&IDs, PFDs and what else? 3

[Procman]

I have previously asked about strip P&IDs vs. sheets and got the answer I wanted. However, most of the response I got was, as I can figure it out based on US standards and the petrochemical industry. Apparantly things are totally different in the paper industry! I was told that PFDs and P&IDs are a thing of the past, that I should get with the times and draw P&Cs. What are P&C's? Also, the scandinavians drew up their own standards (SSG standards) for simplified PFDs and PFDs. As I can figure out, their simplified PFDs are what I am used to as PFDs and their PFDs are "glorified" PFDs but are not P&IDs yet. They also took the ISA standards and changed them. I need to draw up new standards for the company for process engineering flow sheets. Should I stick with PFDs and P&IDs and if so, can someone please give me detailed definitions of both. Should interlocks be shown on P&IDs. Where do you draw the line? What is shown on the P&ID and what is shown on loop diagrams? Remember, we are an international company with mills in Africa, Europe and America. I can therefore not use OSHA as a reason why certain things should be on P&IDs as this only applies for the states and not for Africa and Europe.

 

[Montemayor]

Procman:

Let's agree on one thing: This is about safety[/] and correct, proper operation of processes. As such, I wouldn't give a hoot what Scandinavians, Africans, Frenchmen, or any other non-US agency or govenment entity thinks or believe. The above principles are universal and anyone who doesn't agree is definitely not of any intellectual importance. The above values are just as important to other countries as they are here in the USA. This is not a preference or an ego contest - it's about safe, efficient, and progressive engineering.

I spent more than 25 years traveling, designing, constructing, and operating plants in foreign countries under taxing and difficult conditions and I can state with experience that you will not fail to satisfy a foreign country's desires and wishes if you give priority to what you consider important:

1) safety of the individuals operating the process;
2) safety of all humans outside the process;
3) protection of all equipment;
4) detailed accurate data, calculations, and information over the process at all times;
5) detailed accurate data, calculations, and information on all changes done to the process
6) detailed accurate data on all chemicals and hazardous materials dealt within the process.

If you comply with the above basic guidelines, you will probably be complying with 99% of what all countries are striving for (& considerably more than what they presently obtain from existing processes in their domain).

Local "Standards" for types of diagrams and nomenclature (such as symbology, acronyms, etc.) are "Mickey Mouse", political or nationalistic ploys done by politicians or beaurocratic morons who don't know where to look for personal political gain. These things are minor and sometimes have to be complied with in order just to continue to do business in that country. France has a bad reputation for this kind of attitude - but it's of little or no importance in the engineering area. You will find that internationally, engineers always agree on common-sense and effective, practical controls. I've never found any difference in the attitudes of engineers from one country or another. We all think the same and we don't wear our nationalistic or political colors on our sleeves. We are practical and down-to-earth in resolving and controlling problems.

I am confident that your fellow engineers from other countries will agree with you on the basic control documents being the PFDs and the P&IDs.

Read my comments about the interlocks and the P&IDs in your other post in this forum.

I hope this helps.


Art Montemayor
Spring, TX

 

[dcasto]

Art can also apply the same to companies. I've seen companies create their own standard drawings for the sake of standards and not on assist operations with following the process. The concept of all streams entering the left and leaving the right sides is great, but if the drawing becomes so complex, what then?

With all the mergers and acquisitions, a new problem arises with compy mandated standards. A plant that has excellent drawings that everyone who works there has to redraw them to satisfy some bureaucrat in the new owners home office isn't making the plant safer.

Listen to what operations want and apply published standards to meet their needs.

 

[psafety]

Procman,
I currently work in the Paper Industry, as a process safety engineer. My work is for a "global" company. Art has spoke the gospel.

P&IDs are our "standard".

Don Coffman

 

[cawse001]

If you are looking for consistency across borders try the ISO standard.

IS010628 1997 (E). Flow diagrams for process plants - General rules.

The standard is written more as a guideline rather than a proscriptive document. It covers PFD's and P&ID's.

It also references other standards with respect to the symbology that should be used.

Cheers,

NB

 

[Procman]

Thanks guys. I fully agree with what all of you have said. However, you gave me enough info to support my point of view but not to convince the other engineers to change! I will have to refer to the SSG standards in our new standards as these are used by most of the consultants we use (being scandinavian). For one person to totally change an industry is impossible! However, I can try and improve on what is currently used. I will take a look at the ISO standards. The PFDs as referred to in the SSG standards, also use ISO as a reference. However, instrumentation only is shown on drawings. Instrumentation functional codes are simplified to only two letters, you wouldn't for instance have a TIC. It would only be a TC. Also, no transmitters are shown. The assumption, they say, should be made that if you have a Temperature Control, as an example, you will have a transmitter. It is a given, so why show it?

Anyway, I will continue my fight to upgrade and standardise drawings in our company. Thanks for the support.

 

[Canoman]

Just to throw it out there, I work for a process engineering firm in the refining industry that has clients worldwide, and we ALWAYS use PFD's and P&ID's.

I've seen PFD's and P&ID's for projects in the USA, Canada, Mexico, Brazil, Venezuela, England, Sweeden, Isreal, Ghana, Korea, India, Bahrain, and Saudi Arabia just to name a few.

I realize that the pulp & paper industry differs from refining, but if it works for refiners all over the world, it should work for other process industries as well.

 

[ddeopc]

i like this

 

[Biggy]

What about ELD's (Engineering Line Diagrams)?

 

[Graybeard]

I have been an active design engineer for over 30 years and much of that time has been as an A/E serving chemical and paper plants in the US. If there is anything that is standard, it's that there is no standard. Some of the companies I have been exposed to as an A/E had corporate standards, which I was told by the local plant manager did not apply to his plant. What one company calls a P&ID another calls a P&CD, still another uses the tem ICD (Instrument control diagram). About the most you can hope for is to reach an compromise with other stakeholders. Corporate standards (in the best cases) are arrived at by addressing the collective wants, needs, and experience of all stakeholders. I've seen P&ID's that even include the wiring panel circuit breaker number. Others that are little more than block flow diagrams with active/critical controls identified. P&ID's have fewer standards than maps. On MOST maps North is up.

 

[Procman]

What would typically be reflected on an EFD?

 

[Procman]

Graybeard,

You are the first person that understands the difficulty we have in the pulp and paper industry. Plant engineers think nothing applies to them. They have not yet experienced the advantage of P&IDs and therefore think it is just another paperwork excercise.

Regards
Procman

 

[FrancisL]

Take a look to at thread124-63685

 

[Graybeard]

EFD - Engineering Flow Diagram, some refer to as a Mechanical Flow Diagram, or a Piping Flow Diagram, or there are prob. other names that other firms use. All diagrams are more or less schematics provided to illustrate that portion of the system intended viewer or the producer deems important. Some will have the piper has his prospective, the IE his prospective, the EE, the ChE, the production engineer. It's interesting to see, for instance the Mech. Engineer will produce a drawing the show the temperature control on a paper machine and he may represent as a single TIC bubble connected to a steam valve. The IE gets hold of it, and that single bubble gets represented as as TE-TI-TT-TIC-TISH/L-T-...-TCV. i.e. he will show the 1 bubble as 4 to 16, with 1 to 7 signal lines off each bubble. And if it's an active pressure device, at least 2 and perhaps 8 additional valves used for calibration purposes. It's not uncommon to see drawings that have so many instrument and electrical lines on them that you it's very difficult to visualize the actual process. This use to be more of a problem than it is not. With the advent of CAD, rather than arguing over what should or should not be on a single diagram, now with a little good preplanning everyone can have their own version, based on their interest. I am personally seen instances where at least 5 different types of diagrams have been produced on relatively simple processes for different illustration purposes.