Working Depth

Working depth, abbreviated as WD, is the depth of engagement, when two mating gear meshes with each other.  This is a measure of the depth of engagement between two meshing gears.  It is an important parameter in gear design and is used to ensure proper tooth strength and load carrying capacity and essentially the portion of the tooth depth that is actively involved in transmitting power.

Clearance is the space between the tips of the teeth of mating gears to account for manufacturing tolerances, misalignments, and variations in operating conditions.  The working depth, therefore, represents the effective depth of the tooth engagement, excluding the clearance.

The working depth is a factor in determining the capacity of gears to transmit loads without tooth failure.  Proper consideration of working depth, along with other geometric parameters like addendum, dedendum, and pitch diameter, is essential for designing gears that can operate reliably and efficiently in various applications.

 

Working Depth formula
\(\large{ WD \;=\; A_g + A_p  }\)     (Working Depth) \(\large{ A_g \;=\; WD - A_p  }\) \(\large{ A_p \;=\; WD - A_g  }\)
Symbol	English	Metric
\(\large{ WD }\) = working depth	\(\large{in}\)	\(\large{mm}\)
\(\large{ A_g }\) = addendum of gear	\(\large{in}\)	\(\large{mm}\)
\(\large{ A_p }\) = addendum of pinion	\(\large{in}\)	\(\large{mm}\)