The thread flank diameter is the effective diameter of a threaded spindle in the area of the thread flanks, where the force is transmitted between the spindle and the nut. It lies between the outer diameter and the core diameter of the spindle and is often referred to as the mean thread diameter.
The spindle flange diameter is critical for:
- Power transmission between the spindle and the nut
- Calculation of Friction, Efficiency, and Torque
- Strength and service life calculations
- Determination of the angle of inclination and the angle of friction
Since the load is transmitted primarily through the thread flanks, this diameter is particularly important for the mechanical design.
Alignment within the thread profile
- Outer diameter: maximum diameter across the thread peaks
- Flank diameter: Diameter at the level of the thread flanks
- Core diameter: the smallest diameter at the bottom of the thread
Technical Application
In calculations, the spindle flange diameter is used to:
- determine the required drive torque
- calculate the efficiency of the screw drive
- determine contact pressures on the flanks