Helical gears are often the default choice in applications that are suitable for spur gears but have non-parallel shafts. They are also used in applications that require high speeds or high loading. Regardless of the load or speed, they generally provide smoother, quieter operation than spur gears.
Helical gears have teeth that are set on an angle to the gear axis. The features and benefits are similar to spur gears, but can be a better option when higher velocities are needed. Compared to spur gears, helical gears have greater tooth strength and a higher load carrying capacity.