MAE 1351 FINAL EXAM STUDY GUIDE QUESTIONS AND ANSWERS VERIFIED 100% CORRECT

MAE 1351 FINAL EXAM STUDY GUIDE QUESTIONS AND ANSWERS VERIFIED 100% CORRECT Baseline dimensioning - ANSWER -All dimensions originating from a base or datum, commonly used for cnc machines that work from a rectangular coordinate system. Can eliminate some accumulation of tolerances, is variable for what you are using it for. Chain dimensioning - ANSWER -features are dimensioned relative to one another (used when a part function requires that features be related to one another) Largest accumulation of tolerance between features. General Notes - ANSWER -Appear in the lower right hand corner of a drawing and apply to the whole drawing Local Notes - ANSWER -Connected to specific features on the views of the drawing. Also known as annotations. Specified with leader lines. Unilateral Tolerancing - ANSWER -All of the deviation is in one direction from the basic size. Tolerance is all above or all below the basic size of the dimension. Bilateral Tolerancing - ANSWER -Where the deviation is divided in some way above and below the basic size of the dimension. The tolerance can be equally or unequally distributed about the basic size. Limit Dimensions - ANSWER -Displayed with the high limit above the low limit. If the dimension is displayed on a single line, the low limit appears before the high limit. Direct dimensioning - ANSWER -Best way to control tendency of tolerances to accumulate. Involves placing a single dimension between 2 key points to minimize tolerance accumulation. Statistical Tolerancing - ANSWER -A way to assign tolerances based on sound statistical practices rather than conventional tolerancing practices. Clearence fit - ANSWER -Specifying the limits of size in such a way that a clearance or space always fits between mating parts. Interference fit - ANSWER -Specifying the limits of size in such a way that an interference of material always exists between mating parts. Transition fit - ANSWER -Specifying the limits of size in such a way that either a clearance or interference fit will exist when mating parts are assembled. Allowance - ANSWER -Difference between the maximum material limits of mating parts. It is the minimum clearance or maximum interference. Tolerance - ANSWER -Total permissible variation of a size, it is the difference between the upper and lower limit. Basic size - ANSWER -size from which the limit dimensions were derived. Clearance - ANSWER -Refers to a fit where there is space in between 2 mating parts. Interference - ANSWER -A fit where the 2 mating parts have intersecting nominal volumes, requiring the deformation of the parts. Hole basis or Basic hole system - ANSWER -the basic size is applied to the lower limit of the hole and is frequently used. Shaft basis or basic shaft system - ANSWER -the basic size is applied to the upper limit of the shaft and is used when several parts are required to fit on a shaft. RC - Running or Sliding Clearance Fit - ANSWER -- Intended to provide running performance with suitable lubrication throughout a range of sizes. - RC9 (loosest) - RC1 (tightest) LC - Locational Clearance Fit - ANSWER -Fits that are intended for parts that are normally stationary but can be freely assembled or disassembled. Range from snug fits for parts requiring accuracy of location to medium clearance fits. LT- Locational transition Fit - ANSWER -These fits are intended where accuracy of location is important but a small amount of clearance or interferences are permissible. LN Locational Interference Fit - ANSWER -These fits are intended where accuracy of location is of prime importance and where parts require rigidity and alignment with no special requirement for bore pressure. FN - Force or Shrink Fit - ANSWER -These types of interference fits are usually characterized by maintenance of constant bore pressures throughout the range of sizes. Loose Running Fit - ANSWER -These fits are wide commercial tolerances or allowances on external members. Free Running Fit - ANSWER -These fits are not for use where accuracy is essential, but are good for large temperature variations, high running speeds, and heavy journal pressures. Close Running Fit - ANSWER -These fits are for running on accurate machines and for ensuring accurate location at moderate speeds and journal pressures. Sliding Fit - ANSWER -These fits are not intended to run freely, but are intended to move and turn freely and locate accurately.