Thrust Washer Selection Calculation
NOTE:
- Perform the thrust washer selection calculation for each on the drive shaft and joint shaft sides.
- Calculate the backlash gap by subtracting constant number A from backlash measurement value.
- Constant number A = 0.090 mm {0.0035 in}
- Backlash measurement value - 0.090 mm {0.0035 in} = backlash gap
Calculation example
- Backlash measurement value = 0.165 mm {0.00650 in}
- 0.165 mm {0.00650 in} - 0.090 mm {0.0035 in} = 0.075 mm {0.0030 in}
- Calculate the thrust washer thickness gap by multiplying the backlash gap by constant number B.
- Constant number B = 1.25 mm/mm {1.333 in/in}
- Backlash gap x 1.25 mm/mm {1.333 in/in} = thrust washer thickness gap
Calculation example
- Backlash gap = 0.075 mm {0.0030 in}
- 0.075 mm {0.0030 in} x 1.25 mm/mm {1.333 in/in} = 0.094 mm {0.0037 in}
- Calculate the thrust washer thickness calculated value by adding the thrust washer thickness gap to the thickness of the thrust washer used in the measurement.
- Thickness of thrust washer used in measurement + thrust washer thickness gap = thrust washer thickness calculated value
Calculation example
- Thickness of thrust washer used in measurement = 0.810 mm {0.8103 mm}
- Thrust washer thickness gap = 0.094 mm {0.0037 in}
- 0.810 mm {0.0319 in} + 0.094 mm {0.0037 in} = 0.904 mm {0.0356 in}
- Calculate the thrust washer thickness on the opposite side in the same way.
- Based on each thrust washer thickness calculated value, select each thrust washer of the appropriate thickness.CAUTION:
- Select the same thickness of the thrust washers on the drive shaft and joint shaft sides. However, if the measurement value cannot be adjusted within the specification, select the different thickness of the thrust washer.
Thrust washer thickness calculated value Appropriate thrust washer thickness (mm {in}) Equal to or more (mm {in}) Less than (mm {in}) 0.925 {0.0364} 1.025 {0.04035} 0.95 {0.037} 0.875 {0.0344} 0.925 {0.0364} 0.90 {0.035} 0.825 {0.0325} 0.875 {0.0344} 0.85 {0.033} 0.775 {0.0305} 0.825 {0.0325} 0.80 {0.031} 0.675 {0.0266} 0.775 {0.0305} 0.75 {0.030} Selection example
- Because shim thickness calculated value 0.904 mm {0.0356 in} applies to 0.875 mm {0.0344 in} or more and less than 0.925 mm {0.0364 in}, a shim of 0.90 mm {0.035 in} thickness is selected.
NOTE:- Constant number A, 0.090 mm {0.0035 in} is the backlash median value of the specification.
- The backlash gap is the difference between the backlash median value of the specification and the backlash measurement value.
- Constant number B is the thrust washer thickness which varies each time the backlash changes by 1.0 mm {0.039 in}. Because the thrust washer thickness changes 0.1 mm {0.004 in} when the backlash changes 0.08 mm {0.003 in}, the quotient is 1.25 mm/mm {1.333 in/in}.
- The thrust washer thickness gap is the difference between the thickness of the thrust washer used in the measurement and the thickness of an appropriate thrust washer. In the formula to calculate the thrust washer thickness gap, the thrust washer thickness gap is calculated by multiplying the backlash gap with constant number B.