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Line List Info on Piping ISOs? 6

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DGrayPPD

Mechanical
Feb 2, 2017
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I am trying to update my company's ISO template to include more information from the line list. In my experience, it increases the efficiency of the spool drafters to have most info on the ISO already. I am getting some push back from my boss who doesn't think that it is necessary to put all the info, however he does not have any experience with fabrication ISOs. I try to show him some reference ISOs from big name firms and company's and he is still hesitant. I know most of the info is tied back to the spec, but would it really be that bad to have the info on the ISO too? I have seen thousands of ISOs from every major company and they all do it a little differently and just in my personal opinion I liked having it on there because it made my job quicker and more efficient. See below for a list of my current template info.

 
 http://files.engineering.com/getfile.aspx?folder=1c7d2140-295c-4c12-ba2d-684ece990b6a&file=Capture.PNG
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We have some basic (minimum) info on the isometric as well, which serves several purposes. One of which is that our manufacturer (almost always) has to fullfill PED requirements and hence apply CE-marking to the spools .He therefore needs some minimum info on the drawing to check if and which module is applicable. Also, the insulation guys who insulate the piping spools need to have info for their work. Having as much info in 1 place makes it easier for a lot of people, who otherwise have to combine multiple documents to get their required information.

The downside is that the iso now serves so much purposes/disciplines that it can become a bit overwhelmed by data. From your example I would e.g. leave the design code out, as the line spec already has this defined, and doesnt really add much for the people fabricating and installing the spool. The other values from your png attachment are however all present on our iso's as well.

All in all I would say you need to decide what should be on there, based on the the purposes of the drawing, and disciplines involded. Also, try to input you're data as much as possible on 1 place; having multiple locations where you (e.g.) define your design temp. can easily lead to mistakes (2 different values for 1 parameter). We prevent this by having 1 line list database, and linking our P3D/CAD database to that file.
 
Never show the same information more than once.
If for some reason you must show more than once, be sure that your project specifications define which location's information shall prevail in case of discrepancy and also require that anybody noting such a discrepancy submit a clarification request to project management in writing.

Reaction to change doesn't stop it :)
 
No. Isometrics should show the line number and refer to the same line number on the line list. Iso should show nothing other than dimensions, directions and other fabrication details.

And a north arrow.

Reaction to change doesn't stop it :)
 
I have secret powers! :)

'DGray' and 'PPD'. Hmmm...

SPED member lookup.

dgray_ppd2_vnxu8l.png


I'm the SPED admin (among other things).

Paul
 
DGray,
here is another slant on the subject.
When you consider ALL the different people who use the Piping Isometric and the many reasons for that use, you will lean towards more information than less. With that in mind I agree with your list with the exception of Design Temp and Pressure as has been noted.
- I would add the Hydro Test Pressure
- Once the Piping Material Spec is created and Approved then the Design P&T is not normally used by anyone or needed.
- People who want less information on the Piping Isometric have never been at the jobsite doing a Punch-List at the top of a Fractionation Tower and some key point is only on the Line List.

I support your idea on this subject. However, being retired for 17 years I don't know what my former company (Fluor) is doing today but I know what we did back then.


Sometimes its possible to do all the right things and still get bad results
 
Thank you for all the insight. The only reason I still have the design temp and pressure is because I have seen it pretty regularly on ISOs. Not sure if it is necessarily needed, but IMO it can't hurt either.
 
As XL83NL writes, your line list (called LDT -line designation table, I think- in some places) information should be pulled into the iso from the database. For checking, I prefer more info on the iso, as opposed to less.

In the "old days", information duplication could be a real problem unless rigorous work processes were enforced.
 
Gator is correct. We use an LDT file (which has xlsx file extension) which allows the line list data (from an MSAccess database) to be downloaded into ACAD Plant3D.

I've seen different opinions on this subject. BI is right as well, except that nowadays automazation allows us, when applied and managed correctly, to define data at one place and then reference it at multiple other places; therefore reducing the paperwork.
 
Right. Referencing is just sending the same stuff to various print or read locations and is not the same as having the information stored in two or more independent locations, which should always be avoided.

Reaction to change doesn't stop it :)
 
For the PE who has to stamp the iso - having a note that says "See Line List" for the design conditions and hydrotest pressure is a bit like signing a blank check.
 
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