Compliance with ASME Y14 11

[Adesilva]

I would like to know people's thoughts on compliance with ASME Y14. I work for a 75 years old company that will be increasing its global manufacturing presence with our sister companies and outside vendors. We have 40,000+ drawings and are a design/configure to build manufacture with 500-600 new parts per year and about 3,000-4,000 "standard" parts we have historical usage.
Part of this process was a review of our current drawing standards. We purchased 13 standards (Y14.1, 14.2 etc) and after a six month review, I discovered that we are not in compliance per the standards. The discrepancies vary but the drawings generally comply with accepted drawing conventions. One of the biggest points is our use of symbols. For example, we use a triangle with a number for revisions instead of the supported circle with a letter. There are a number of other examples but that should suffice as an illustration.
I would like to know if people see this as a rigid set of documents that must be adhered to in all aspects or a general guideline that you can pick and chose. Most 3D CAD platforms don't follow all of the conventions shown in the standard anyway (i.e. section through a rib). Does anyone follow this set of standards to the letter, and if not, to what degree do you deviate? The issue of appropriate application of GD&T symbols (Y14.5) is a whole other issue and separate from this current debate. Half of the department wants to make the change and the other half change only what is essential as being 100% compliant would take thousands of man hours redrawing our most used drawings all the while we are in the midst of a PDM implementation. I would like to hear all views from as many companies as possible

 

[ctopher]

Most companies I have been with in the past were strict about following the standards, I agree with it.
For the past several years I have seen a decrease in their use, especially with outsourcing and less employees to have time to comply.
My current company does not use them much. I hope it changes soon.

Chris
SolidWorks 10 SP4.0
ctopher's home
SolidWorks Legion

 

[KENAT]

You've pre-empted my comment somewhat in so much as it's arguably more important to comply with 14.5 than some of the others. In fact some of the others don't give as much detail as might be desired, such as rules for assy drawings.

For things like your rev indicator, I wouldn't lose sleep over it. So long as your company procedures clearly indicate what the triangle means, and so long as you let any affected parties - such as vendors or customers - know what it means you're fine. That particular instance is one that came up just the other day and we pretty much all agreed that limiting it to circle seemed unfortunate - especially as a circle is the only shape shown for assy balloons in 14.24 as I recall.

I usually try and stick to them closely unless it's going to cause a real problem. A few times I've deviated from them later to regret it. Some CAD packages can't fully comply with every aspect of the standard. That said on the rib, I believe the standard does allow the type of true view that CAD generates if you look in the text. CAD packages may also do things that the standard don't support - such as dimension to hidden lines and projecting views from sections etc.

Most of the standards generally use 'should' these days instead of 'shall' so arguably you can not follow them that closely and still be compliant.

The closer you follow the better. The important thing is to document and circulate any significant deviations.

In your case you may choose to make new drawings follow more closely but not religiously update old drawings. Do your older drawings explicitly reference any drawing standard?

Of course, if your contract says you have to comply with ASME Y14.100, then that's another matter.

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[Adesilva]

I'm trying to avoid sending different formats to the shop so I need to pick a path an follow it. So if I change my symbols, I will have to revise the older prints to comply so as to not confuse the shop. I personally see our deviations as minor and have documented them. A review of the older drawings (DWG/TIF) show that the old title blocks make no mention to a standard and we do not engage in work with clients that would mandate compliance to Y14.100.

Great comments so far.

 

[MikeHalloran]

If the shop staff is so dumb that they can't deal with two drawing styles at once, you've got problems that drawing standards don't address.

Go ahead and change the style for new drawings, and just leave the old ones untouched. Change the style one at a time as they have to be redrawn. A big campaign to redo all your existing drawings is just going to introduce new errors, and distract everyone.





Mike Halloran
Pembroke Pines, FL, USA

 

[MadMango]

I agree with Mike. Don't try to update all your drawings at once. Make all new drawings per the ASME standards, and update all drawings going through a revision change. Some training may be in order if people out on the manufacturing floor have never encountered GD&T Symbols should also be considered.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of these Forums?

 

[dgallup]

We had to make the change more than a decade ago from obsolescent company drawing standards to internationally recognized standards. We choose to go with ISO standards because a) our new owners were French, b) most of our customers were European, c) you can pick and choose which ISO standards to implement like a Chinese menu. We wrote our own document explicitly stating which standards were implemented and any exceptions (like invoking the envelope rule). By doing that we were able to avoid changing all the old drawings. We have continued with this set of standards even though we are American owned now.

 

[pmarc]

I would be very careful with adjusting existing drawings to Y14 standards. This can generate a lot of work and - even if done correctly - may cause more troubles than benefits.

As other folks said, it seems to be more reasonable to start using Y14 stds. on new drawings, step by step, that all employees (designers, inspectors, manufacturers) have a chance to get used to it. If your company did not use Y14 standards before it could be a shock for lot of people. Probably a GD&T training will be additionally needed to explain rules, symbols as well as advantages of GD&T language over traditional dimensioning.

For me the most important point to remember is that switching to Y14 standards requires completely different approach to a product design, inspection and manufacturing. You will quickly notice that the issue with triangles or circles as revision symbols is really nothing comparing to many other roadblocks.

 

[MintJulep]

Take some time to search though posts here in this forum.

You will find many threads along the lines of "I have this drawing in front of me and it has some symbol that I've never seen and can't find in any drawing standard and I don't know what it means."

Compliance with standards avoids having one of your drawings becoming the reason for a post of that type.

 

[ctopher]

I agree with pmarc. It can be more work doing the switch and updating current dwgs. IMO, it's worth it in the long run...

Chris
SolidWorks 10 SP4.0
ctopher's home
SolidWorks Legion

 

[MikeHalloran]

Worth it in the long run? Maybe.

Lets's say you have 40,000 drawings.

A good designer in days of yore could produce ~2 a day. Let's say a good CAD driver can redraw 4 a day.
That's still 10,000 person-days.

In the US now, a good CAD driver costs, what, $50/hr?
Call it $200 per person-day.

That's 2 million dollars, which comes right off your bottom line; no immediate return for the expenditure, no increase in sales, just a hope for unquantified future savings.

How many outfits have that kind of dough lying around these days?
If you know of one, please tell me; I'll be at the door tomorrow.



Mike Halloran
Pembroke Pines, FL, USA

 

[MintJulep]

Add to Mike's analysis the additional costs associated with the new errors that are guaranteed to be introduced in the process of otherwise needlessly revising drawings.

 

[Adesilva]

I'll add one more wrinkle to the discussion. We’re part of an internationally based parent division that has a drafting standard based on ISO and they use a triangle for their revisions. Our VP of Engineering has already told them we will not be using their standard but most of our future outsourcing will be with sister company that do follow it.

 

[fcsuper]

Adesilva,

I believe I ready addressed this point in my response on the SolidWorks Forum:

https://forum.solidworks.com/message/166020

Matt Lorono
Lorono's SolidWorks Resources & SolidWorks Legion

http://groups.yahoo.com/group/solidworks & http://twitter.com/fcsuper

 

[SteveMartin]

I try to follow the ASME standards as written, but (written) company standards can and do take precedence - just make sure that the company standard is referenced on the prints and available to anyone who needs to interpret your drawings. I try to avoid company standards that conflict with the ASME standard, but we have a couple that linger.

If I had my way, we'd match the ASME standards exactly, but that hasn't happenned yet.

 

[pmarc]

Adesilva,

I do not know if your Engineering dept. is the only one in your company which is declining to use ISO drawing standards, but I am sure that when different sites of the same company use different standards it is a first step to having serious troubles.

But I would like to go back for a moment to one of your original questions: should the set of ASME Y14 standards be adhered in all aspects or be only a general guideline that can be picked and choosen? There is a very good example of a company which basically follows ASME standards, however has got its own addendum that takes precedence whenever something is doubtful or even modifies standards when necessary. The company is called GM. They know that for instance Y14.5 standard ("Geometric Dimensioning and Tolerancing") is not perfect, specifies general rules only, shows relatively simple examples, has got some vague areas even, so it is good as a basis but not as an absolute. The products they deal with require much more detailed specifications and that's why an extra document must be defined to serve as a guideline every time when the standard is not enough.

And I think in many cases the situation will be similar. If a company produces something which is only a little bit more complicated than the figures in the standards it should have additional document(s) which will say how to deal with these wider aspects of design, drafting etc.

 

[PeterStock]

Our client company is involved in aerospace. They also use ASME Y14.5M-1994. But they have an companuy spec that is also referenced on the drawing. This takes care of things like default tolerances (none are given on the drawing) and some other areas where a different approach is needed or desired.

Peter Stockhausen
Senior Design Analyst (Checker)
Infotech Aerospace Services

http://www.infotechpr.net

 

[MintJulep]

For example: thread1103-276296

 

[fsincox]

Mint,
You must see the same irony here I do!
Frank