Sprockets is often classified into standard sprockets, HK sprockets and other sprockets.
1. Standard sprocket
Common sprockets are ANSI sprockets which could be engaged with typical series roller chains. See P125 for dimensions.
You'll find two types 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. Nonetheless, sprockets for a number of strand chains are distinctive from regular sprockets in sprocket tooth profile.
three. Other sprockets
Other sprockets are intended according on the following calculation formulas to suit respective specialty chains.
The sprockets utilised for the following chains 
will be the same since the conventional sprockets in tooth gap type, but distinctive in tooth thickness (sprocket tooth profile).
4. Calculation of sprocket dimensions
The dimensions of standard sprockets along with other common sprockets are calculated as follows. At the outset, the diameters of sprockets are calculated from the following calculation formulas.
Following, sprocket tooth profile (the form in the tooth determined by its thickness) is calculated from the following calculation formulas. (The values shown from the following pages had been calculated by these formulas and thought to be the standard values.)
Calculation formulas for diameters and tooth gap forms Calculation formulas for diameters
Calculation of pitch diameter, tip diameter and caliper diameter
The fundamental dimensions of the sprocket suitable to get a chain pitch of one mm are respectively termed pitch diameter issue, tip diameter aspect and caliper diameter element. The respective aspects for respective numbers of teeth are listed beneath. If these variables are multiplied by chain pitch, the essential dimensions of the corresponding sprocket may be obtained.
Illustration:
In the case of 80 (25.40 mm pitch) with 35 teeth Pitch diameter (Dp) ＝ P×Pitch diameter element
Calculation formulas for tooth gap kinds
Because the most rational tooth gap varieties in which the strain angle alterations in response towards the elongation of a smoothly rotated roller chain together with the lapse of service time, ANSI specify two varieties of tooth profiles: U-type and S-type. On the whole, S-type tooth profiles are adopted in accordance with ANSI, and our common sprockets also have S-tooth profiles.
