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Shaft support - what is it?
Shaft support - what is it?

The layout of the guide shaft and support bearings is a very cheap and profitable way of linear movement. In the production of CNC machines, it is very often used. Also used for the manufacture of modern 3D printers, milling systems and even plasma cutting machines.

Particularly appreciated in mechanical engineering due to its positioning accuracy. The material used for precision shafts is very dense, high carbon steel with alloying qualities. Elements are heat-hardened and ground to ensure high tool life and very low friction levels.

Support breaks

Features of support bearings

  1. Working temperature should be between 15 and 100 degrees Celsius.
  2. Working hardening of the surface should be HRC60-64.
  3. From 0.5 to 4 levels, the degree of hardening should reach.
  4. Total shaft diameter - necessarily from 5 to 70 mm.
  5. 6500 mm is the maximum allowable length.

If you choose a shaft, pay special attention to the overall flexibility of the design on large diameters, and in comparison withrail counterparts, the accuracy should be relatively lower.

Use a shaft on a support to eliminate unnecessary deflection. Longitudinal directions on the shaft provide an unlimited travel length and a very high bearing capacity. The cardan shaft support bearing and blocks must be selected depending on what task they face.

The main thing you should focus on is the design and load capacity. Often the dimensions and parameters of bearings differ from each other, mostly insignificantly, it all depends on the manufacturer and the standards that were followed in the manufacture of this part. The main role of the conductor to the drive axle of the car is assigned directly to the transfer case, and the cardan drive does the work.

Bearings - and there are the main parts of the support shaft. It is important to remember that the adjustment and adjustment of the safety clutch must be carried out in the transmission of torque. And the torque for tightening the nut must be between 50 and 70 hm. Please note that the shaft support cannot be abused or abused.

support beam

The support shaft is considered almost the main part among all the components of the car's transmission. It is also called an outboard bearing. The responsibilities of this mechanism include supporting the cardan shaft.

This system is divided into two types:

  • non-removable (when you exit work, you need to change the entire system);
  • replaceable (can be removed and replaced with a new one).

What is a rolling bearing shaft

Rolling bearing is a ready-made assembled structure, consisting of two inner and one outer rolling ring. Between them there are 2 rocking figures and four separating straps, whose job is to keep the parts at an acceptable distance.

The bearing is considered the most well-assembled part of the mechanism and is used in many systems. An exception is made for structures in which the sliding of parts is provided. They are standardized and go on sale from special state production facilities. It should be noted that Russia is the European leader in the production of bearings. Until the 1980s, more than one billion of these parts were produced a year - in different sizes and diameters.

support spring


  • high frictional stability;
  • low enough price for mass production;
  • small support length;
  • reduced lubricant consumption;
  • very low starting torque;
  • they can be completely replaced - this is a huge plus when assembling the movement;
  • low sensitivity to warps and kinks.

The cons are as follows:

  • high level of shock sensitivity;
  • low speed, which is associated with the swing dynamics of the structure;
  • if produced in single or small quantities, the cost is very high;
  • high radial building dimensions;
  • limited operating temperature (through a peculiar form);
  • if we take the bearing of a general example, it will not work inaggressive environment.
  • Support repair

How everything works

The outboard bearing is also called a frame structure, which provides easy sliding, extending the life of the friction reduction.

Such an intermediate shaft support has an inner and outer rings, their duties include supporting the bearing and preventing it from moving. If the part is of high quality, it consists of a dense and solid metal. There are also some elements of high-strength rubber, which is very resistant to friction. It is attached with a bracket to the car frame.

Required support

Fault indicators

If while driving a car you notice an extra sound in the form of a hum or whistle (there may also be a knock), this is a clear sign of a broken support shaft. Remember that in this case the radius of the car also changes. There is a kind of trembling that is transmitted to the interior of the car when driving.

Bearing device

The system is represented by a frame with a hole in the form of a cylinder in the center, there is a sleeve made of a special metal with anti-faction elements.

For smooth rotation, the gap between the shaft and the support is lubricated with oil for easy movement. It helps to reduce the friction force during the movement of structural elements. If we talk about the inner or outer rings, then their quality must be at the highest level, they must be made of the most durable metal. The rubber that is inpart of the cardan shaft, must be wear-resistant to reduce the force of vibration.

Support properties:

  • high resistance to various types of loads;
  • vibration absorption;
  • low sound during operation;
  • quite compact size;
  • good exposure to aggressive environments and working conditions;
  • easy replacement or repair.
support apparatus

Symptoms of a failed bearing

To more accurately determine the breakdown, it is worth trying to hear sounds while the car is coasting, it is good to take acceleration and release the gas pedal. After such manipulation, you should hear a certain hum or whistle. In some cases, there is even a howl.

How can I replace the support

The driveshaft bearing (throttle) is easy to replace and can be carried out by the driver himself without the help of auto mechanics, but the process must be done properly.

All you need:

  1. Open-end wrenches 12 and 13 mm.
  2. Instructor (made of good metal).
  3. Standard hammer.
  4. Pliers will be needed to remove the support rings.
  5. Bearing puller.
  6. To replace a new support.

Take the car to the car pit. The engine should be turned off and left in first gear. Place some type of wheel chock under the wheels of the machine to ensure safety during operation. Lubricate all parts between the bearing well with grease (WD-40) before operation.

If you are changing the driveshaft support, it is better to change immediatelycross, as their service life is also very low. All fasteners in the form of bolts should be unscrewed. Pull out the inner flange (it is attached to the tail of the machine) and then only remove the support shaft fasteners.

Usually, the shaft is fixed with fasteners in the form of leaves or petals, they should be removed. Secure the shaft you removed in a vise and unscrew the bearing bolt. To remove the fork, use a special puller, and remove the bearing with light knocks on it.

Use a rag to completely wash the place for attaching a new bearing. Lock the stopper towards the rear of the vehicle. Fasten the protective washer and nut, these elements should definitely be centered. When the intermediate shaft bearing with bearing is securely fastened, install the shackle shaft in its place.

support bolt


It is important to remember that the intermediate bearing of the cardan shaft must be changed no later than the end of its service life. But it is best to change it much earlier, since the strong influence of an aggressive environment and careless driving very quickly disables the chassis of the car. And better - carry out a technical inspection of the car once every few months, this will help you notice and prevent breakdowns in time even before serious problems appear.

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