Enter the helix angle (deg) and the coefficient of friction into the calculator to determine the Lead Screw Efficiency. 

Lead Screw Efficiency Formula

The following formula is used to calculate the Lead Screw Efficiency. 

Elead = tan(ha) / (tan(ha + arctan (f))) *100

  • Where Elead is the Lead Screw Efficiency (%)
  • ha is the helix angle (deg) 
  • f is the coefficient of friction 

How to Calculate Lead Screw Efficiency?

The following two example problems outline how to calculate the Lead Screw Efficiency.

Example Problem #1:

  1. First, determine the helix angle (deg). In this example, the helix angle (deg) is given as 50.
  2. Next, determine the coefficient of friction. For this problem, the coefficient of friction is given as .65.
  3. Finally, calculate the Lead Screw Efficiency using the equation above: 

Elead = tan(ha) / (tan(ha + arctan (f)))

Inserting the values from above and solving the equation: 

Elead = tan(50deg) / (tan(50/57.2958 + arctan (.65))) = 14.5 (%)

Example Problem #2: 

Using the same process as above, first define the variables required by the formula. In this case, these values are:

helix angle (deg) = 30

coefficient of friction = .76

Entering these values yields:

Elead = tan(30deg) / (tan(30deg + arctan (.76))) = 24.22 (%)