Question

A 20 mm hole shaft assembly results in minimum and maximum clearances of 0.03 mm and 0.2 mm, respectively. The hole has a unilateral tolerances with zero fundamental deviation. If the tolerance on the shaft is 0.08 mm, the minimum size of shaft is

• A. 19.67 mm
• B. 18.55 mm
• C. 19.89 mm
• D. 20.00 mm

Answer 1

The correct option is C 19.89 mm

Minimum clearance L.L. of hole - U.L of shaft

Maximum clearance U.L of hole - L.L of shaft

L.L. of hole - U.L. of shaft 0.03 mm

U.L of hole - L.L. of shaft = 0.2 mm

U.L. of shaft - L.L of shaft = 0.08 mm

Hole has unilateral tolerance with zero fundamental deviation

$\therefore$L.L. of hole = 20 mm

U.L. of shaft=20 – 0.03 = 19.97 mm

L.L of shaft = 19.97 – 0.08 = 19.89 mm