Dynamic Profile Questions - ASME Y14.5-2018

[AndrewTT]

1) Figure C-6 (Comparison of Symbols) shows that the ISO standard also has a Dynamic Profile Tolerance. Did ASME add this b/c ISO was going to/had already added this feature? Did the two groups come up with this idea together?

2) Are there measurement devices/software that can handle a dynamic profile requirement? To all inspectors out there, how would you inspect a Dynamic Profile tolerance (assume a block with in irregular shaped hole)?

3) Can the Dynamic Profile Modifier be used in more than one refining segment of a profile control? An example of this would be a 4 level compound profile FCF (see attached image). If I put the Dynamic Profile modifier in the 4th level (.010 no datums), can I then also put it in the third level (.020 A)? This would allow the size of the irregular hole to now be limited by the second level (.050 A/B) while the form remains limited by the 4th level (.010 no datums). This is a theoretical question at this point. I do not have a real world application in mind.

 

[axym]

AndrewTT,

1. Looking at Fig. C-6, the entry for dynamic profile in ISO isn't correct. ISO has something similar, but it's not called dynamic profile and the delta symbol is not used. ISO has the concept of an offset zone - the UZ symbol offsets the zone by a specified amount, giving a result similar to ASME's unequally disposed profile. The OZ symbol offsets the zone by an unspecified amount, giving a result similar to ASME's dynamic profile. I don't have the standard in front of me - pmarc can probably provide further details or corrections.

The two standards groups didn't come up with the idea together. I don't know all the reasons why ASME added this or if ISO's developments had anything to do with it, but I remember it being discussed as early as 2012.

2. I use a software package called SmartProfile, that handles both the ASME dynamic profile and the ISO OZ. It's part of the Evolve suite by Kotem.

3. I don't see any reason to put restrictions on the use of the dynamic profile modifier. It simply opens up an additional degree of freedom for the profile tolerance zone - ISO calls it offsetting, ASME calls it "progressing". I don't have a problem with your proposed multi-segment example.

Evan Janeshewski

Axymetrix Quality Engineering Inc.

http://www.axymetrix.ca

 

[pmarc]

1. I confirm what Evan said. The OZ symbol in ISO works in the same way as dynamic profile modifier in ASME. In ISO there is no triangle symbol for that application. More details about OZ can be found in ISO 1101:2017 and ISO 1660:2017.

To me it is evident that the two groups did not meet / work together. The brightest example is introduction of 'from-to' modifier by Y14.5-2018 whereas at almost the same time, in 2017, ISO decided to withdraw this modifier (they had it from 2012).

One additonal comment to figure C-6. This is another great example of how information can be manipulated. Leaving the error that Evan mentioned aside, I think that the table may and will create very false impression that the two systems - ASME and ISO - are pretty much similar. It is all because its idea is basically to show how/if ISO covers all the symbols that exist in ASME. If, however, the idea was reversed, i.e. if the table were to show how ASME covers exisiting ISO symbology, there would be a looot of empty cells in the ASME column.

3. I agree with Evan on that.

 

[AndrewTT]

Thank you both.

 

[greenimi]

....to show how ASME covers exisiting ISO symbology, there would be a looot of empty cells in the ASME column.

pmarc,
Why do you think if is shown "NONE" (as currently is the verbiage used) that is an empty cell?
Just me talking....

Anyway, thank you for your pertinent input.

 

[SeasonLee]

2) Are there measurement devices/software that can handle a dynamic profile requirement?

From the link below, we learned Hexagon had noticed the draft on Dynamic Profile at June 13 last year, so I'm sure PC-DMIS already update their software accordingly.

https://www.gagesite.com/documents/...al Changes to ASME and ISO GD&T Standards.pdf

A profile tolerance zone is static and controls both the form and size of ...

My question is all of us will concentrate on the new term Dynamic Profile, but what is static profile tolerance zone? Can I understand this way: They are all static profile tolerance zone if no dynamic profile modifier on the FCF callout?

Season