This article on GD&T was written by Rick Hughes, a friend of mine from the ASME standards community. Rick was kind enough to let me publish this article on his behalf. I think you will find it interesting.
In May of 2020, I conducted a survey to find out which versions of the Y14.5 standard is dominant in various industries. The survey also included a few questions on related topics that often come up in discussions about standards. The results are a bit of a surprise.
First, I would like to offer my sincere thanks to all who participated in the survey. Without your help, I could not have found this information.
The survey had 178 responses from over 20 different industries. The number of responses is not huge, but I feel it does give a fair indication of which standards are made use of in various industries.
I recognize the survey results are not entirely representative of all companies due to the limited sample size. However, I believe it provides information that is worth analyzing. I concluded five main points from the survey. These points are my opinions based on the survey responses and my observations working with companies across many industries.
If you need GD&T training, one-on-one mentoring, drawing reviews, or help in resolving a drawing dispute, contact me to discuss how I can assist you.
If you would like a .pdf version of this article, send me an email at alex@krulikowskiconsulting.com
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This article on GD&T was written by Rick Hughes, a friend of mine from the ASME standards community. Rick was kind enough to let me publish this article on his behalf. I think you will find it interesting.
A few weeks ago, I surveyed on the interpretation of size dimensions based on Y14.5. I posted the survey on several group boards on LinkedIn. This article compiles the results of the survey.
Before I discuss the results, I would like to thank all the people that participated in the survey. Their contribution allows all of us to look at the questions in this survey from many users viewpoint.
I use these surveys as the "voice of industry" in my work on standards committees. I also believe they are helpful for the readers to know how their use of tolerancing concepts compare to others around the world.
The purpose of this survey was to find out if various groups in industry interpret and verify the minimum limit (or local size) of size dimensions.as a two point requirement or as a theoretical swept sphere requirement. . (The survey does not address the effects of Rule #1)
The figure above shows the GD&T and Inspection skill levels of the survey participants. This information is important because it shows that most of the responses came from very knowledgeable participants.
The chart above shows that the main two areas of participation were from Engineering/design and quality/inspection. The questions were designed for the engineering community and the inspection community.
The intent of the question in the figure above is to determine if the participants felt the requirement for the minimum size limit should be verified with a two-point measurement or a theoretical spherical ball.The responses show that the majority (67%) of participants feel that a two-point measurement can be used to verify the minimum limit of a size dimension. However, there is not a uniform interpretation in industry.
A few descriptions from the "Other" responses on how the minimum size limit should be verified are below.
The question in the figure above is similar to the previous question about a diameter. It is interesting that when presented with a block even more people selected the response of the two point measurement.
A few descriptions from the "Other" responses on how the minimum size limit should be verified are below.
The question in the figure above asked the participants to select an answer based on the Y14.5 -2009 standard. The two point measurement still has the highest response rate. The chart shows there is variation in the interpretation of a size dimension.
The figure above shows that the amount of tolerance is the most significant factor in the choice of a measurement device for the minimum limit of a size dimension. I am a bit surprised that the standard referenced on the drawing did not score higher.
The figure above shows the two-point measurement (micrometer/caliper) is the most common method for verifying the minimum limit of a size dimension in industry. closely followed by CMM verification. I find it interesting that the swept ball algorithm is rarely used.
These survey results are based on participant responses from 27 countries. There were 147 participants total. 61% of the responses were from the U.S. and the remainder from the international community. The highest response rates internationally were from India, Canada, and Great Britain.
Although the participation is significant, it is not high enough to make an accurate assessment of the interpretation of size dimensions in industry, but, it does provide us with information to make useful insights on the topics even though it is not a definitive answer.
The survey results indicate that the minimum limit of a size dimension is not uniformly understood by engineers, designers, quality personnel, and inspectors in industry. The variation in understanding size dimensions is partially because this topic is not covered thoroughly in the Y14.5 and Y14.5.1 standards.
In a number of cases, any of the methods used to verify the lower limit of a size dimension described in this survey would be adequate for the function of a part. However, in certain cases, the method of verifying a size dimension can make a difference between a functional part and a failed product. (e.g. minimum wall thickness, allowable roundness deviation, etc.)
If you create drawings, precise communications can make the difference between a successful product and failure. Where the interpretation of the minimum limit of a size dimension can make a difference in the function of your part, I recommend that you specify how the size dimensions should be interpreted (or verified).
Do you intend the minimum limit of size dimensions to be interpreted as a two point requirement (as implied in Y14.5) or as a theoretical swept ball requirement (as shown in Y14.5.1)?
Until the Y14.5 and Y15.1 standards adequately cover how to interpret size dimensions, consider one of the following actions:
In hindsight, I can think of several additional questions that would have been useful to ask in this survey. It is always a trade-off between the depth and length of these studies. If you have an opinion on how many survey questions would not discourage participants, leave a comment or send me an email. Thanks.
I hope you found the survey results informative. If you like the article, please share it with your friends on on social media. Feel free to leave a comment about your experiences with size dimensions or on any aspect of this article.
Thanks again to all the survey participants.
Welcome to part three of the article on addendums. It covers a few tips on creating and implementing an addendum in your organization. How to implement an addendum is just as important as the creation process.
This section covers a few tips on creating an addendum. The tips are divided into three parts; useful information, tips for creation, and typical pitfalls to avoid.
The list below contains an example of useful information for creating an addendum. All of the items may not apply to your organization.
The list below contains an example of useful information for creating an addendum. All of the items may not apply to your organization.
The list below contains common addendum pitfall . All of the items may not apply to your organization.
This section covers a few tips on implementing an addendum. The tips include approvals/buy-in, distribution, and training. All of these tips may not apply to your organization.
Hopefully, some insights were gained with this brief look at addendums. As you may have noticed, I am an advocate of using addendums in large corporations. Developing an addendum renews the focus on the importance of drawings.
In a survey I conducted, I found that about 30% of the companies in the survey use addendums (or some sort of supplement to the Y14.5 standard), and about 15% mentioned that they felt an addendum would be useful in their company.
If you would like to see an example of an addendum, you can purchase a copy of the GM addendum by clicking the button below.
Does your company use an addendum? Do you have any suggestions for items that should be in a Y14.5 standard addendum? If so, add a comment below.
If you would like assistance in creating a corporate addendum, contact me at Alex@KrulikowskiConsulting.com
A few weeks ago, I surveyed on whether the ISO GPS or ASME Y14.5-2009 standard is more widely used on drawings in industry. I posted the survey on several group boards on LinkedIn. This article compiles the results of the ISO GPS and ASME Y14.5 standards survey.
Before I discuss the results, I would like to thank all the people that participated in the survey. Their contribution allows all of us to look at the questions in this survey from many users viewpoint.
NOTE:
Since the survey is comparing the use of the Y14.5 (a US standard) and the ISO GPS (an International standard) standards, the results are shown as a comparison of US responses and International responses.
The figure above shows that the International response rate was slightly higher than the US response rate. There were 133 total responses from 27 different countries. The US had 63 responses and their were 70 responses from the International community. The highest response rates of the International participants were from India, Poland, and Brazil.
The survey had participants from a variety of industries.
The survey responses came from employees working in companies from less than 100 to over 100,00 employees. The chart above shows that 53% of the participants work in companies with more than 10,000 employees.
The first three questions of the survey are focused on gathering information about the participants. Their country and the industry they work in and the size of the company. The next section of the article will explain details about which tolerancing standards are used on drawings in their companies..
Whether the ASME Y14.5 or ISO GPS standard is more widely used on drawings is the main question in the survey. My students and customers have often asked me this question. My colleagues in the ISO GPS and ASME standards community talk about it as well.
The survey shows that the ASME Y14.5 standard is widely used (86%) in the US and is used significantly Internationally(56%).
This survey is based on 133 responses from 27 countries. Although the participation is significant, it is not high enough to make an accurate assessment of the use of tolerancing standards in industry globally. However, it does provide us with information to make useful insights on the use of standards even though it is not a definitive answer.
Keep in mind; the question below is asking an opinion of the participants.
When asked, "If your company was evaluating which tolerancing standards to use in the future, what would be your recommendation?"
Most of the participants (67%) responded the ASME Y14.5 tolerancing standard as their preference and both ASME Y14.5 and ISO GPS as their second choice (20%).
The three most common responses from the US participants are below. The standard they recommended is shown in bold. (The number in parentheses is the number of participants with similar comments.)
The three most common responses from the International participants are below. The standard they recommended is shown in bold.(The number in parentheses is the number of participants with similar comments.)
A few additional interesting comments from individual US survey participants are below.
A few additional interesting comments from individual International survey participants are below.
Based on the survey responses, I feel that the survey suggests three things:
I hope you found the survey results informative. If you liked the article, please share it with your friends on Linkedin. Feel free to leave a comment about your experiences with these standards or on any aspect of this article.
For all of my colleagues in the ASME and ISO standards committees, I am just the messenger of the survey responses.
Thanks again to all the survey participants.