This document discusses measurement tolerances, including bilateral and unilateral tolerances. It defines clearance fits as having total clearance between two parts, while interference fits have total interference. Examples are provided for determining the maximum and minimum clearance or interference between parts based on their tolerances. Converting between unilateral and bilateral tolerances is also demonstrated. The document aims to help readers practice working with tolerances through examples of clearance and interference fits.

1. Measurement ChapterMeasurement Chapter
Bilateral and Unilateral ToleranceBilateral and Unilateral Tolerance
Clearance and Interference FitClearance and Interference Fit
© Southwest Wisconsin Technical College 2006

2. ToleranceTolerance
 Bilateral ToleranceBilateral Tolerance
 2.355”2.355” ±± 0.005”0.005”
2.355”
2.350”
2.360”
0.005”
0.005”

3. ToleranceTolerance
 UnilateralUnilateral
 1.480”1.480”
+0.000”
-0.007”
1.480”
1.473”
0.007”

4. ToleranceTolerance
 UnilateralUnilateral
 12.85 mm12.85 mm
+0.01 mm
-0.00 mm
12.85m
12.86mm
0.01 mm

5. Convert: Unilateral to BilateralConvert: Unilateral to Bilateral
1.295”
1.285”
0.010”
+0.000”
-0.010”
1.295”

6. 0.010”
Convert: Unilateral to BilateralConvert: Unilateral to Bilateral
1.290”
1.285”
Min.
1.295”
Max.
0.005”
0.005”
+0.000”
-0.010”
1.295”1.290” ± 0.005”

7. ConvertConvert 2 of 22 of 2
 Convert the unilateral tolerance to a bilateralConvert the unilateral tolerance to a bilateral
tolerance.tolerance.
 4.885”4.885”
+0.004”
-0.000”
4.889”
4.885”
0.004”
Min. Max.±

8. Measurement ChapterMeasurement Chapter
Clearance and Interference FitClearance and Interference Fit

9. Clearance FitClearance Fit
Total Clearance

10. Clearance FitClearance Fit
Total Clearance

11. Range of Clearance FitRange of Clearance Fit
 Maximum ClearanceMaximum Clearance

12. Range of Clearance FitRange of Clearance Fit
 Minimum ClearanceMinimum Clearance

13. Determine ClearanceDetermine Clearance 1 of 21 of 2
 Determine theDetermine the maximummaximum andand minimumminimum clearanceclearance..
A: 1.25” ± 0.03”
B: 1.18” ± 0.03”
Max A: _______
Min A: _______
Max B: _______
Min B: _______
1.28”
1.22”
1.21”
1.15”
Maximum Clearance = Largest Hole – Smallest Pin
Maximum Clearance = 1.28” – 1.15” = 0.13”

14. Determine ClearanceDetermine Clearance 1 of 21 of 2
 Determine theDetermine the maximummaximum andand minimumminimum clearanceclearance..
A: 1.25” ± 0.03”
B: 1.18” ± 0.03”
Max A: _______
Min A: _______
Max B: _______
Min B: _______
1.28”
1.22”
1.21”
1.15”
Minimum Clearance = Smallest Hole – Largest Pin
Minimum Clearance = 1.22” – 1.21” = 0.01”
= 0.13”

15. Determine ClearanceDetermine Clearance 2 of 22 of 2
A
B
2.0360” ± 0.0005”
2.0334” ± 0.0005”
Max A: _______ Min A: _______
Max B: _______ Min B: _______
2.0339” 2.0329”
2.0365” 2.0355”
Maximum Clearance = Largest B – Smallest A
Maximum Clearance = 2.0365” – 2.0329” = 0.0036”

16. Determine ClearanceDetermine Clearance 2 of 22 of 2
A
B
2.0360” ± 0.0005”
2.0334” ± 0.0005”
Max A: _______ Min A: _______
Max B: _______ Min B: _______
2.0339” 2.0329”
2.0365” 2.0355”
Minimum Clearance = Smallest B – Largest A
Minimum Clearance = 2.0355” – 2.0339” = 0.0016”
Max Clearance= 0.0036”

17. Interference FitInterference Fit
Total
Interference

18. Interference FitInterference Fit 1 of 11 of 1
 Determine theDetermine the maximummaximum andand minimumminimum
interferenceinterference..
A
B
Diameter of Pin:
9.94 mm ± 0.03 mm
Diameter of Hole:
9.85 mm ± 0.03 mm
Max A: _______ Min A: _______
Max B: _______ Min B: _______
9.97 mm 9.91 mm
9.88 mm 9.82 mm
Maximum Interference
= Largest A – Smallest B
Maximum Interference
= 9.97 mm – 9.82 mm = 0.15 mm

19. Interference FitInterference Fit 1 of 11 of 1
 Determine theDetermine the maximummaximum andand minimumminimum
interferenceinterference..
A
B
9.94 mm ± 0.03 mm
9.85 mm ± 0.03 mm
Max A: _______ Min A: _______
Max B: _______ Min B: _______
9.97 mm 9.91 mm
9.88 mm 9.82 mm
Minimum Interference
= Smallest A – Largest B
Minimum Interference
= 9.91 mm – 9.88 mm = 0.03 mm
= 0.15 mm

20. WorksheetWorksheet
 Part I :Part I : Work with bilateral and unilateralWork with bilateral and unilateral
tolerance.tolerance.
 Part II:Part II: Convert unilateral tolerance to bilateralConvert unilateral tolerance to bilateral
equivalent.equivalent.
 Part III:Part III: Solve clearance and interferenceSolve clearance and interference
problems.problems.

21. The EndThe End
 Written by Peter C. EsserWritten by Peter C. Esser
 Southwest Wisconsin Technical CollegeSouthwest Wisconsin Technical College
 ©©2006 & 20072006 & 2007
 pesser@swtc.edupesser@swtc.edu