Manufacturing process, productivity and cost are often determined by component tolerances. If components are incorrectly toleranced, it leads to assembly problems. Too tight a tolerance leads to higher cost. Designers are expected to tolerance components optimally.
Dimensional variations in production parts accumulate or stack up statistically and propagate through an assembly kinematically, causing critical features of the finished product to vary. Such variations can cause costly problems, requiring extensive rework or scrapped parts. One of the effective tools for managing variations is Tolerance Analysis. Tolerance Analysis is a quantitative tool for predicting the accumulation of variation in an assembly by performing a stack-up analysis, reduces manufacturing costs by improving producibility and also enables design engineers to determine, how robust a design is at the drawing phase.
Keeping this in view, Indian Machine Tool Manufacturers' Association (IMTMA) is organizing a 3 days programme on Tolerance Stack-Up Analysis on 22 - 24 October 2018 at Pune, covering worst case tolerancing as well as statistical methods.

• Understanding of stacks and why do we need it
• Statistical tolerancing, Process capability indices and 6 Sigma
• Loop diagram and the dimensional objective or critical functional relationship to analyze
• Calculate nominal output and statistical variation using statistical methods
• Worst case tolerance calculation, WC
• Effect of dimensioning practices on tolerance variation
• Root Sum Square, RSS and Modified Root Sum Square, MRSS
• Empirical correction factors, Bender, Gilson, Gladman, and Greenwood
• Geometric Dimensioning & Tolerancing, application in Stacks analysis
• Part stacks using bonus tolerance and datum shift, Float and biased floats
• Effect of form and orientation tolerances in Stacks
• Assembly stacks using profile, run out and position

After undergoing the programme, the participants will be able to -
1. Understand stack-up analysis and why it is required in today’s design.
2. Analyse and optimize the designs for ease of manufacturing and assembly while keeping functionality intact.
3. Identify the critical tolerances which require tighter tolerance control or statistical process control, SPC.
4. Enlarge drawing tolerances and thereby reducing cost of design.
5. Develop robust design with low risk of failure.