Generally speaking, the worm gear is a kind of transport mechanism. It can be used to transmit power in a lot of industrial fields. This transport mechanism is made up of two parts. It includes worm wheel and worm. The form of the worm is similar to the screw.

As a kind of the drive arrangement, the worm gear has its own unique features. The transport mechanism has the high transmission ratio. Meanwhile, it has the big axial force. In addition, its structure is more compact than the structure of bevel gear. In virtue of the above-mentioned features the drive mechanism is widely used in a lot of places.

In the following passage, we will talk about the advantages and the disadvantages of this drive mechanism in detail.

First, let us discuss the advantages of the worm gear. Compared with the bevel gear, the worm gear has the better meshing effectiveness and also it has the higher transmission ratio. What's more, the worm gear is a kind of screw drive. The main transport form is the meshing drive. Therefore, the transmission is more stable and the vibration is smaller. This drive type is very applicable for the machines which work in stable working states. Last but not least, compared with other transport mechanics, the biggest advantage of the worm gear is its self-locking function. When the lead angle of the worm is smaller than the friction angle of the meshing gear, this transport mechanism will generate the reverse self-locking. At this time, the worm can drive the worm wheel,but it is impossible for the worm wheel to drive the worm. This self-locking function makes a great contribution to the safety of machines.

Second, let us analyze the disadvantages of the worm gear. As far as we know, everything has two sides just like a coin. There is no exception for this transport mechanism. The transmission efficiency of this transport mechanism is very poor. In addition, the abrasion is very serious in the transmission process. Why does this transport mechanism have these shortcomings? It is related to its drive form. The drive form of the worm gear  is the meshing gear transmission. The fast sliding speed results in the abrasion of tooth flanks. In order to reduce the abrasion of tooth flanks, the expensive materials are used by this transport mechanism. Therefore, the cost of the worm gear operator is increased. The price is more expensive.