与平键联接比较，花键联接在强度、工艺和使用方面有下列特点：在轴上与毂孔上直接而均匀地制出较多的齿与槽，故联接受力较为均匀；因槽较浅，齿根处应力集中较小，轴与毂的强度削弱较少。

Compared with the flat bond connection, the spline connection has the following characteristics in strength, process and use.More teeth and grooves are made directly and evenly on the shaft and hub hole, so the joint force is more uniform.

Because of the shallow groove, the stress at the root of the tooth is ***all, and the strength of the shaft and hub is weakened less.

渐开线花键的定心方式为齿形定心。受载时齿上有径向力，能起自动定心作用，有利于各齿受力均匀，强度高，寿命长。用于载荷较大，定心精度要求较高以及尺寸较大的联接，如航空发动机、燃气轮机、汽车等。压力角45°的花键多用于轻载、小直径和薄型零件的联接。

The involute spline is centering in the shape of the tooth. The tooth has radial force on the tooth, and it can play the role of automatic centering, which is beneficial to the uniform force of each tooth, high strength and long life. It is used for large load, high precision and large size connection, such as aero engine, gas turbine, automobile and so on. The spline with a pressure angle of 45 degrees is used for the connection of light, ***all diameter and thin parts.

凡是在轴毂联接中不用键、花键或销时的联接，统称为无键联接。无键联接中我们介绍两个常用的型面联接和过盈配合联接。

The connection of no key, spline or pin in the hub connection is called the keyless connection. In keyless joins, we two commonly used type face joins and interference fit connecti.

装夹后产品靠近活动钳口附近容易上翘、抬起，多次装夹一致性差。传统机用虎钳的螺旋副间隙较大，在使用中会产生较大振幅的振动；而活动座和虎钳体之间的滑动接触面较大，采用的间隙也较大。

After the clamping, the product is easy to and lifted near the movable jaw, and the cistency of the clamping is poor many times. The spiral pair clearance of traditional machine vice is bigger, which will cause large amplitude vibration in use. The sliding contact between movable seat and jaw vice body is larger, and the gap used is bigger.