Non-standard custom nuts have small radial size and large bearing capacity. They are often used for shafting transmission under low-speed and heavy-load conditions. High-precision and dynamically balanced drum-shaped with brake discs. Non-standard custom shaft can be used for high-speed transmission. , such as the shafting drive of a gas turbine. It is composed of an external toothed bushing with a drum-shaped tooth thickness and a coupling pair composed of an internal gear ring suitable for it. Relative to the continuous growth of technology, there are more and more drum-shaped  with brake disc drum teeth with standard high-precision, heavy-duty hard tooth surface. Heavy-duty and high-precision drum gear couplings in foreign countries attach importance to the material of low-carbon alloy and high-quality steel, which is milled and ground after thermal treatment, with high machining precision. .

Drum gear coupling with brake disc is composed of inner gear ring with the same number of teeth and flange half coupling with outer teeth. The outer teeth are divided into two types: straight teeth and drum teeth. The drum tooth is to make the outer tooth into a spherical surface, the center of the spherical surface is on the axis of the gear, and the tooth side clearance is larger than that of the general gear. Improve the contact conditions of the teeth, improve the ability to transmit torque, and prolong the service life. The contact state along the tooth width with angular displacement.