120 likes | 228 Views
12. Practical Applications and Calculation Methods. Calculate position tolerances when more than two parts are stacked in a floating fastener or fixed fastener application. Distribute the total available position tolerance between features to which position tolerances are applied.
E N D
12 Practical Applications and Calculation Methods
Calculate position tolerances when more than two parts are stacked in a floating fastener or fixed fastener application. • Distribute the total available position tolerance between features to which position tolerances are applied. • Specify projected tolerance zones for fixed feature locations to prevent interference conditions. • Determine the amount of tolerance accumulation in a simple assembly.
Properly use zero position tolerances at MMC to increase manufacturing freedom. • Apply paper gaging techniques to determine if a produced part meets drawing requirements.
Floating Fastener Condition— Two Hole Sizes & Distributed Tolerances
Fixed Fastener Condition—Two Parts, Unevenly Distributed Tolerances
Zero Position Tolerance at MMC • Zero tolerancing at MMC increases manufacturing freedom • Clearance conditions must exist • Located feature must have a size tolerance • Lets the manufacturer choose how to allocate the tolerances
Paper Gaging Techniques • Measure hole locations relative to datum reference frame • Calculate coordinate variations • Calculate diameter position variations • Plot coordinate variation values