`T_"applied" = ( F * d_m ) / 2*(( "l" + pi * mu * d_m ) / (pi* d_m + mu * "l" ))`

Enter a value for all fields

The Lowering Torque for a Leadscrew calculator computes the torque required to lower a load with a square thread power screw assembly.

INSTRUCTIONS: Choose units and enter the following:

• (d_m) This is the effective screw diameter
• (l) This is the lead
• (F) This is the force created when torque is applied
• (μ) This is the coefficient of friction between screw and nut

The Math / Science

The Leadscrew Lifting Torque equation is:

   `T_R= F*d_m/2((l+pi*μ*d_m)/ (pi*d_m + μ*l)) `

where:

• TR is the torque required to lower a load using a Square Thread Power Screw assembly.  Friction Coefficients 
• d_m is the mean thread diameter
• l is the lead
• F is the load
• μ is the coefficient of friction for thread