Sprockets might be classified into regular sprockets, HK sprockets along with other sprockets.
1. Regular sprocket
Normal sprockets are ANSI sprockets which could be engaged with standard series roller chains. See P125 for dimensions.
There are two forms of tooth profiles: U-tooth and S-tooth.
two. HK sprocket
HK sprockets is usually engaged with HK series roller chains, and these for single strand chains are identical to normal sprockets. Nonetheless, sprockets for numerous strand chains are unique from standard sprockets in sprocket tooth profile.
three. Other sprockets
Other sprockets are made according towards the following calculation formulas to suit respective specialty chains.
The sprockets utilised for the following chains are the 
identical because the standard sprockets in tooth gap type, but distinctive in tooth thickness (sprocket tooth profile).
four. Calculation of sprocket dimensions
The dimensions of normal sprockets and also other standard sprockets are calculated as follows. Initially, the diameters of sprockets are calculated through the following calculation formulas.
Subsequent, sprocket tooth profile (the form of the tooth dependant upon its thickness) is calculated from the following calculation formulas. (The values shown within the following pages had been calculated by these formulas and regarded as the typical values.)
Calculation formulas for diameters and tooth gap types Calculation formulas for diameters
Calculation of pitch diameter, tip diameter and caliper diameter
The fundamental dimensions of the sprocket ideal for any chain pitch of 1 mm are respectively named pitch diameter issue, tip diameter issue and caliper diameter component. The respective elements for respective numbers of teeth are listed below. If these components are multiplied by chain pitch, the essential dimensions in the corresponding sprocket might be obtained.
Illustration:
In the situation of 80 (25.40 mm pitch) with 35 teeth Pitch diameter (Dp) ＝ P×Pitch diameter element
Calculation formulas for tooth gap types
Because the most rational tooth gap types in which the pressure angle adjustments in response on the elongation of a smoothly rotated roller chain using the lapse of services time, ANSI specify two kinds of tooth profiles: U-type and S-type. Normally, S-type tooth profiles are adopted in accordance with ANSI, and our regular sprockets also have S-tooth profiles.