Zerol tooth strains
Zerol bevel gears are an intermediate sort in between straight and spiral bevel gears. Their tooth are curved, but not angled. Zerol bevel gears are designed with the intent of duplicating the traits of a straight bevel gear but they are made employing a spiral bevel chopping method.
china bevel gears
The benefit of the spiral tooth above the straight tooth is that they have interaction far more steadily. The contact among the enamel commences at a single end of the gear and then spreads throughout the complete tooth. This outcomes in a much less abrupt transfer of power when a new pair of tooth arrive into play. With straight bevel gears, the abrupt tooth engagement leads to sounds, particularly at high speeds, and influence tension on the tooth which tends to make them not able to consider weighty hundreds at large speeds with out breaking. For these motives straight bevel gears are typically restricted to use at linear speeds significantly less than a thousand ft/min or, for tiny gears, below 1000 r.p.m.[three]
Spiral tooth lines
Main article: Spiral bevel gear
Spiral bevel gears have their enamel formed along spiral traces. They are somewhat analogous to cylindrical type helical gears in that the tooth are angled however, with spiral gears the teeth are also curved.
Straight tooth lines
In straight bevel gears the teeth are straight and parallel to the china bevel gear turbines of the cone. This is the easiest sort of bevel equipment. It resembles a spur gear, only conical relatively than cylindrical. The gears in the floodgate picture are straight bevel gears. In straight bevel gear sets, when every single tooth engages it 
impacts the corresponding tooth and simply curving the gear teeth can fix the problem.