Hot Installation Cross Shaft Universal Coupling

Hot Installation Cross Shaft Universal Coupling


As a kind of coupling, universal coupling uses the characteristics of its mechanism to make the driving shaft and driven shaft not on the same axis. When there is an angle between the axes, it can realize the continuous rotation of the two shafts, and reliably transfer torque and motion. Compared with the common coupling, the most outstanding feature of universal coupling is that its structure has larger angular compensation ability, compact structure, and high transmission efficiency.

Universal coupling with its superior performance, the market sales are very considerable, there are many kinds of universal coupling on the market. So how to choose the right coupling? Among them, the spider type universal coupling is a kind of universal coupling with a large amount of consumption, and the bearing of this kind of universal coupling is the most easily damaged part. Generally speaking, the car will choose the ball cage universal coupling. For agricultural machinery, industrial machinery, and other sports machinery, the special universal coupling will be used, and most of the hoisting equipment will use cross shaft universal coupling.

How to Hot Install the Cross Shaft Universal Coupling?

1、 Preparation Before Hot Installation

Use gasoline or kerosene to fill and scrub the matching parts of the journal and the cross universal coupling. If there is a rough or damaged situation, it needs to be eliminated with an oilstone or fine diamond gauze, of course, other methods can also be used. Then use a micrometer to measure the internal diameter of the journal, and use a micrometer to measure the internal diameter of cross universal coupling. At least 3 points shall be measured when measuring the coupling, and repeated measurement shall be carried out. If the treatment result does not meet the requirements of the drawing, the inner hole shall be repaired with a scraper or half-round file.

2、 Hot Installation

After the preparation work, start the hot installation, which is required to be fast, so as to avoid that the temperature drops before the hot installation are completed, resulting in the reduction of the aperture of the cross shaft universal coupling and the difficulty of hot installation. Generally, the temperature of the universal coupling of the hot installed spider type will be heated to 250 ℃. Heating temperature should not be too fast, so as not to affect the temperature uniformity of the coupling, and the heating time should be determined according to its expansion. In order to obtain a reasonable inner diameter of the coupling, a measuring stick of the same size can be made according to the expansion value of the measured heating until the measuring stick can be put into the inner diameter hole. Then carry out the heat jacket work.

The surface of the universal joint should be carburized, quenched, or tempered. The hardness of the surface is different with different methods. Gas carburizing puts the workpiece into a closed carburizing furnace and obtains a high carbon surface layer through the gas (methane, ethane, etc.) or liquid carburizing agent (kerosene or benzene, ethanol, acetone, etc.). Solid carburizing is to put the workpiece and solid carburizing agent (composed of charcoal and accelerant) in a sealed box, heat it in the heating furnace to the carburizing temperature and keep it for a certain time so that the atoms of the universal coupling of activated carbon penetrate into the workpiece surface, which is also the earliest carburizing method.

The universal coupling with the cross shaft is a universal part of the mechanical foundation, which is suitable for two shafts with skew axis and frequent change of relative position. The biggest advantage of the cross shaft universal coupling is that it has the ability to transmit torque, angle compensation, and compact structure.

Structure Principle of Cross Shaft Universal Coupling:

The cross pieces on the driving and driven shafts are connected with the cross shafts in the middle by hinges respectively. When there is the angular displacement between the two shafts, the shaft forks rotate around their fixed axes, thus making the cross shafts move in space.

Motion Analysis of Cross Shaft Universal Coupling:

When the angle between the two shafts is not zero, the actual angle between the driving shaft angle and the driven shaft angle at any instant: the plane comes from the driving shaft 1, is the motion plane on the driving shaft fork 1, the plane is perpendicular to the driven shaft 3, and is the motion of point C on the driven shaft fork.

The Choice of Cardan Shaft and the Cause of Unbalance

The Choice of Cardan Shaft and the Cause of Unbalance


Cardan shaft is used to connect two shafts together so that the two shafts cannot be separated when the machine is working. Only when the cardan shaft is taken down can the two shafts be separated.

There are many kinds of cardan shafts. When selecting the application, the cardan shaft needs to transfer the actual rotation speed of the shaft, how much load it can bear, the installation accuracy required to connect the two shafts, whether the shaft is stable and won't shake when rotating, the purchase price, etc. When purchasing, users need to understand the performance of cardan shaft and their respective characteristics and adopt a cardan shaft suitable for their own equipment. If you choose to use it after purchase, you should give feedback to the manufacturer in time if you have any problems, and do not wait for the final equipment strike to repair. In fact, the best thing is to describe clearly the requirements of the equipment as the manufacturer when purchasing, so that the manufacturer can make a reasonable recommendation.

Cardan shaft is used to realize the continuous rotation of two shafts of different mechanisms, and it can reliably transmit torque and motion of mechanical cardan shaft parts. The feature of the mechanism is that the two axes are not on the same axis, and there is an included angle with the axis. The biggest characteristic of cardan shaft is that it has large angular compensation ability, compact structure, and high transmission efficiency. During the operation of cardan shaft, the transmission imbalance or vibration is often encountered. In order to improve the transmission efficiency of cardan shaft and make it work smoothly, it is necessary to understand why such a phenomenon occurs, so as to find solutions.


Causes Affecting the Unbalance of Cardan Shaft:

1. There is a deviation in the design of parts, or the material is unqualified, or the wear is uneven.

2. The centering surface of the universal joint and the shaft is eccentric, resulting in imbalance.

3. The gap between parts of the universal joint is unreasonable, or the distribution of accessories is uneven and asymmetric.


The Reasons for the Vibration of Cardan Shaft are as Follows:

1. The balance sheet is not compensated by the action balance.

2. The universal joint is not on the same plane.

3. The cardan shaft has broken the original dynamic balance.

4. Worn splines or excessive clearance.

Cardan shaft is a kind of transmission parts. It makes use of the characteristics of its mechanism to make the two shafts, not on the same axis and turn continuously at a certain angle. The biggest characteristic of cardan shaft is that it has large angular compensation ability, compact structure, and high transmission efficiency. There are many types of cardan shafts, among which the cross shaft type is the most common and the ball cage type is the second. In practical application, Cardan coupling can be divided into heavy, medium, light, and small according to its transmission torque. In order to better use the cardan shaft, it is necessary to know what conditions will cause damage.

1. Human factors: improper selection, low machining accuracy of Cardan shaft, poor maintenance, poor alignment, etc.

2. Environmental factors: corrosion caused by the deterioration of lubricating oil, corrosion caused by acid and alkali gas, etc.

3. Damage caused by wear: the cardan shaft runs continuously in the machine, and the components in relative motion are worn.

4. Cardan shaft and fracture: the fatigue limit of Cardan shaft is exceeded, resulting in component fracture.

5. Connecting bolt: improper design, selection, and installation of connecting bolt.

Coupling is a kind of mechanical part used to connect the driving shaft and driven shaft in different mechanisms and make them rotate together to transmit torque. In high-speed and heavy-duty power transmission occasions, some couplings can also play the role of buffering, damping, and improving the dynamic performance of shafting. The coupling is composed of two parts, which are respectively connected with the driving shaft and the driven shaft. Generally, the power machine and the working machine will not be directly connected but will be connected with the working machine by means of the coupling.

As a special kind of coupling, cardan shaft, because of its structural characteristics, makes the driving shaft and the driven shaft not in the same axis, and can realize the continuous rotation of the connected two shafts when there is an angle between the axes, and reliably transfer torque and motion. The biggest difference of cardan shaft lies in its large angular compensation capacity, compact structure, and high transmission efficiency. That's why cardan shafts are so popular.

How to Install Cardan Shaft?

 

Cardan Shaft

How to Install Cardan Shaft?

1, When installing the cardan shaft, should check the product type on the specification model, and clear the flanges of cardan shaft .

2, For the cardan shaft with length compensation, should check the two ends of the forkhead phase, not at the same time, should be corrected by changing the position of the spline teeth.

3, When install, must not hammer the joint bearing.

4. Flange connecting bolts can only be worn from the flange end of the joint, the NUT is screwed by the flange side of the cardan shaft, and if the space of the joint is restricted, the double head bolts can be selected (except for special requirements).

5, Flange connection should use 10.9 class high-strength bolts and 10 high strength nut, twist the nut before the thread part of the bolt and daub a little grease.

6, Bolts, nuts need to have reliable measures to prevent loose.

7, When install should pay more attention to prevent the internal spline slips off.

8, In the possible cause of the operation of the cardan shaft caused by the damage of the site to add a universal shaft protective cover.

Cardan Shaft

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