What Are the Characteristics of Universal Joints Shaft?

The universal joint shafts of modern rolling mills are all balanced by hydraulic balance. The advantage is that the adjustment of the universal joint shafts is very convenient when changing rolls. The principle is basically the same as the balance principle of the upper roll described later. In recent years, in order to overcome the shortcomings of poor lubrication and serious wear of universal joints, cross-shaft universal joints have been widely used, and there is a trend to gradually replace open slide universal joints. Except for universal joint shafts, the principles and adjustments of other types of joint shaft balance methods are similar to the above.

The balance of cardan shafts are all hydraulically balanced. The rolling pressure of the blooming mill is very large, so generally closed stands are used. The difference between the closed stands and the general frame is that the lower part of the front and rear columns of the archway has a hole and a dovetail groove for installing the frame roller, and the dovetail groove is also used for installing the frame roller. That is the place for two rack rollers on each column of the rack.

The rack roll is set on the blooming mill. The reason is that in the first few rolling passes, the rolled piece is very short. In order to adapt to the weight balance, there are slots on each side of the inner side of the window on the upright column of the frame for accommodating the balance top rods, and the two slots are corresponding two through holes on the lower beam of the frame.

As mentioned earlier, universal joint shafts are generally relatively long and heavy. In order to prevent all the weight of the universal joint shaft from pressing on the forks at both ends, a balancing device for the joint shaft is generally installed. The balance force is generally 10%-30% larger than the weight of the coupling shaft. There are three types of balance devices commonly used in hematite beneficiation process: spring balance, heavy hammer balance and hydraulic balance. Spring balance is generally only used to balance the lower coupling shaft. Because the roll connected by the lower coupling shaft does not need to adjust its position during the rolling process. The upper coupling shaft has a large roll lift during the rolling process. Old rolling mills use heavy hammers for balance, and newer rolling mills use hydraulic balance.