Sprockets is usually classified into normal sprockets, HK sprockets and various sprockets.
one. Regular sprocket
Standard sprockets are ANSI sprockets which could be engaged with regular series roller chains. See P125 for dimensions.
There are two styles of tooth profiles: U-tooth and S-tooth. 
2. HK sprocket
HK sprockets could be engaged with HK series roller chains, and those for single strand chains are identical to standard sprockets. On the other hand, sprockets for a number of strand chains are different from common sprockets in sprocket tooth profile.
three. Other sprockets
Other sprockets are designed in accordance to the following calculation formulas to suit respective specialty chains.
The sprockets applied for that following chains are the same as the conventional sprockets in tooth gap form, but various in tooth thickness (sprocket tooth profile).
four. Calculation of sprocket dimensions
The dimensions of standard sprockets and also other basic sprockets are calculated as follows. In the beginning, the diameters of sprockets are calculated through the following calculation formulas.
Upcoming, sprocket tooth profile (the shape on the tooth dependant upon its thickness) is calculated through the following calculation formulas. (The values proven during the following pages had been calculated by these formulas and thought to be the standard values.)
Calculation formulas for diameters and tooth gap types Calculation formulas for diameters
Calculation of pitch diameter, tip diameter and caliper diameter
The essential dimensions of the sprocket appropriate for a chain pitch of 1 mm are respectively known as pitch diameter aspect, tip diameter aspect and caliper diameter factor. The respective things for respective numbers of teeth are listed below. If these components are multiplied by chain pitch, the essential dimensions of your corresponding sprocket may be obtained.
Example:
Inside the case of 80 (25.forty mm pitch) with 35 teeth Pitch diameter (Dp) ＝ P×Pitch diameter component
Calculation formulas for tooth gap varieties
Because the most rational tooth gap forms in which the stress angle changes in response towards the elongation of the smoothly rotated roller chain with all the lapse of service time, ANSI specify two kinds of tooth profiles: U-type and S-type. In general, S-type tooth profiles are adopted in accordance with ANSI, and our conventional sprockets also have S-tooth profiles.