Spiral bevel gears are typically made from hardened steel. One’s teeth of these gears are usually ground for a far more precise finish allowing for little sound at high speeds. You can specify left hand or right hand based on the direction you have to run the gears
If you have a high speed application that requires a lot of torque then spiral bevel gears are a great choice. The gears run at 90° to one another and have “spiral” shaped the teeth which provides maximum tooth surface get in touch with while rotating. With contact spread over the whole tooth the spiral bevel gear can be run much faster compared to the straight tooth bevel spiral gear china equipment and handle harder starts and stops.
We make spiral bevel gears only for industrial applications.
Worm gears are found in large gear reductions. Gear ratio ranges of 5:1 to 300:1 are typical. The setup is designed so that the worm can turn the gear, however the equipment cannot turn the worm. The angle of the worm is usually shallow and consequently the apparatus is held set up due to the friction between the two. The gear is found in applications such as for 
example conveyor systems where the locking feature can become a brake or an emergency stop.
The model cross-section shows a typical placement and utilization of a worm gear. Worm gears have got an inherent basic safety mechanism built-in to its design since they cannot function in the reverse direction.