Sprockets can be classified into typical sprockets, HK sprockets and other sprockets.
1. Regular sprocket
Standard sprockets are ANSI sprockets which might be engaged with standard series roller chains. See P125 for dimensions.
You can find two varieties of tooth profiles: U-tooth and S-tooth.
2. HK sprocket
HK sprockets can be engaged with HK series roller chains, and these for single strand chains are identical to regular sprockets. However, sprockets for several strand chains are diverse from regular sprockets in sprocket tooth profile.
3. Other sprockets
Other sprockets are built in accordance towards the following calculation formulas to suit respective specialty chains.
The sprockets utilised for that following chains are the similar as the conventional sprockets in tooth gap kind, but distinct in tooth thickness (sprocket tooth profile).
4. Calculation of sprocket dimensions
The dimensions of regular sprockets and other common sprockets are calculated as follows. Initially, the diameters of sprockets are calculated through the following calculation formulas.
Subsequent, sprocket tooth profile (the form with the tooth determined by its thickness) is calculated through the following calculation formulas. (The values shown within the following pages have been calculated by these formulas and thought to be the conventional values.)
Calculation formulas for diameters and tooth gap forms Calculation formulas for diameters
Calculation of pitch diameter, tip diameter and caliper diameter
The basic dimensions of the sprocket ideal for a chain pitch 
of one mm are respectively termed pitch diameter component, tip diameter issue and caliper diameter aspect. The respective aspects for respective numbers of teeth are listed beneath. If these aspects are multiplied by chain pitch, the fundamental dimensions from the corresponding sprocket can be obtained.
Example:
From the case of 80 (25.40 mm pitch) with 35 teeth Pitch diameter (Dp) ＝ P×Pitch diameter aspect
Calculation formulas for tooth gap types
Because the most rational tooth gap types through which the pressure angle improvements in response on the elongation of a smoothly rotated roller chain using the lapse of support time, ANSI specify two kinds of tooth profiles: U-type and S-type. Generally, S-type tooth profiles are adopted in accordance with ANSI, and our common sprockets also have S-tooth profiles.
