A smoothly running assembly process with low a failure rate also depends on whether all parts fit. The specifications regarding accuracy must also be met. On the other hand, low cost is important to have competitiveness. To achieve all this, a good tolerance analysis is essential.
If no tolerance analysis is performed, tolerances are usually chosen on the basis of ‘experience’. This is not necessarily wrong. But one designer has more and/or better experience than the other. In all cases, however, the substantiation of the chosen tolerances is mediocre at best. With a tolerance analysis you do have that good foundation and the chance of success is much greater. Moreover, you are then able to optimize between tolerance and cost.
But what exactly is tolerance analysis? People often talk about making a tolerance budget. And this is not a budget in euros or another currency, but a budget in millimeters (or another unit of length). The starting point is usually a specification that must be met. The second step is to collect those part tolerances that affect the specification. Based on this, you can perform your analysis and optimize all tolerances in such a way that the cost-to-failure ratio is optimal.
I (Jaap Vink) have 25 years of experience with tolerance analysis. At ASML I helped developing the structured, methodical approach. And of course many analyses were performed. I also developed an Excel template for tolerance analysis for ASML. This allows any mechanical designer to set up, calculate and present his analysis in the same way. Through the tolerance analysis course, provided by Mikrocentrum, mechanical designers at ASML learn to work with this Excel template.
After starting Vink System Design & Analysis, I also carried out tolerance analyses at other companies. In addition, from 2015 I teach tolerance analysis for Mikrocentrum. Both the open course and the in-company course. The course is suitable for many companies in all sectors. This is evident from the variety of companies I have taught:
- ACE Engineering bureau;
- Altran Automotive;
- BDR Thermea, central heating boilers;
- BoonEdam, revolving doors;
- Demcon Engineering bureau;
- TU Delft DEMO;
- KROHNE Flow meters;
- KUHN Agricultural Machinery;
- Neways Electronics;
- Petersime Zulte, egg incubators;
- Robojob CNC Automation;
- Spark design, design and functionality;
- VIRO Ingenieursbureau, all locations;
- Zodiac Aerospace.
Of course theory is important in the tolerance analysis. In addition, experience also counts. But perhaps the most important thing is the method of approach. Every design is different and has its own challenges.
However, you must be able to perform a tolerance analysis for each new (or existing) design. And that only works with a structured, methodical approach. Even if the design is complex or unclear, with a methodical approach you will always succeed in conducting a tolerance analysis. Fortunately, you don’t have to find out for yourself with the Mikrocentrum course.