Measurement Chapter Bilateral and Unilateral Tolerance Clearance and Interference Fit
ď›™ Southwest Wisconsin Technical College 2006
Tolerance Bilateral Tolerance 2.355” ± 0.005” 0.005”
”063. 2
0.005”
”553. 2
”053. 2
Tolerance Unilateral 1.480”
-0.007”
0.007”
”084. 1
+0.000”
”374. 1
Tolerance Unilateral 12.85 mm
+0.01 mm -0.00 mm
0.01 mm
mm68. 21
ď Ž
m58. 21
ď Ž
Convert: Unilateral to Bilateral 1.295”
+0.000” -0.010”
”592. 1
”582. 1
0.010”
Convert: Unilateral to Bilateral +0.000” 1.295” 1.290” ± 0.005” -0.010” 0.010”
0.005”
Min.
”592. 1
”092. 1
”582. 1
0.005”
Max.
Convert
Convert the unilateral tolerance to a bilateral tolerance. 0.004”
4.885” -0.000” ±
Min.
”988. 4
+0.004” ”588. 4
2 of 2
Max.
Measurement Chapter Clearance and Interference Fit
Clearance Fit Total Clearance
Clearance Fit
Total Clearance
Range of Clearance Fit ď Ž
Maximum Clearance
Range of Clearance Fit ď Ž
Minimum Clearance
Determine Clearance 1 of 2
Determine the maximum and minimum clearance.
1.28” Max A: _______
A: 1.25” ± 0.03”
1.22” Min A: _______ 1.21” Max B: _______ 1.15” Min B: _______
B: 1.18” ± 0.03”
Maximum Clearance = Largest Hole – Smallest Pin Maximum Clearance = 1.28” – 1.15” = 0.13”
Determine Clearance 1 of 2
Determine the maximum and minimum clearance.
= 0.13” 1.28” Max A: _______
A: 1.25” ± 0.03”
1.22” Min A: _______ 1.21” Max B: _______ 1.15” Min B: _______
B: 1.18” ± 0.03”
Minimum Clearance = Smallest Hole – Largest Pin Minimum Clearance = 1.22” – 1.21” = 0.01”
Determine Clearance A
2.0334” ± 0.0005”
B 2.0360” ± 0.0005”
2.0339” Min A: _______ 2.0329” Max A: _______ 2.0365” Min B: _______ 2.0355” Max B: _______ Maximum Clearance = Largest B – Smallest A Maximum Clearance = 2.0365” – 2.0329” = 0.0036”
2 of 2
Determine Clearance A
2 of 2
2.0334” ± 0.0005”
Max Clearance= 0.0036” B 2.0360” ± 0.0005”
2.0339” Min A: _______ 2.0329” Max A: _______ 2.0365” Min B: _______ 2.0355” Max B: _______ Minimum Clearance = Smallest B – Largest A Minimum Clearance = 2.0355” – 2.0339”
= 0.0016”
Interference Fit
Total Interference
Interference Fit 1 of 1
Determine the maximum and minimum interference.
9.97 mm Min A: _______ 9.91 mm Max A: _______ 9.88 mm Min B: _______ 9.82 mm Max B: _______
A
Maximum Interference
Diameter of Pin: 9.94 mm ± 0.03 mm
= Largest A – Smallest B B
Maximum Interference = 9.97 mm – 9.82 mm = 0.15 mm
Diameter of Hole: 9.85 mm ± 0.03 mm
Interference Fit 1 of 1
Determine the maximum and minimum interference. = 0.15 mm
9.97 mm Min A: _______ 9.91 mm Max A: _______ 9.88 mm Min B: _______ 9.82 mm Max B: _______
A
9.94 mm ± 0.03 mm
Minimum Interference = Smallest A – Largest B B
Minimum Interference = 9.91 mm – 9.88 mm = 0.03 mm
9.85 mm ± 0.03 mm
Worksheet
Part I : Work with bilateral and unilateral tolerance.
Part II: Convert unilateral tolerance to bilateral equivalent.
Part III: Solve clearance and interference problems.
The End
Written by Peter C. Esser Southwest Wisconsin Technical College 2006 & 2007 pesser@swtc.edu