A technician is using a standard 0-1 inch micrometer to measure the thickness of a valve shim. Before measuring, the technician checks the calibration and notes that when the anvil and spindle are closed, the thimble reads 0.002 in. past the zero mark (a positive zero error of +0.002 in.).
When measuring the shim, the edge of the thimble is past the '1' mark on the sleeve, two additional unnumbered graduation lines are fully visible, and the '18' mark on the thimble aligns exactly with the sleeve's horizontal index line.
What is the true thickness of the valve shim?
- 0.166 in.Cevap
- B0.168 in.
- C0.170 in.
- D0.141 in.
Cevap
0.166 in.
The raw micrometer reading is determined by adding the sleeve major number ('1' = 0.100 in.), the visible minor lines (2 lines = 0.050 in.), and the thimble reading (0.018 in.), which totals 0.168 in. Because the micrometer has a positive zero error of +0.002 in. (it reads 0.002 in. when completely closed), this excess must be subtracted from the raw reading. Therefore, 0.168 in. - 0.002 in. gives the true thickness of 0.166 in.
Adım Adım Çözüm
Anahtar Kavram
Micrometer Scale Reading and Calibration Compensation