What to pay attention to when installing and removing rod end bearings

Time：2020.03.02  Source：Roller Bearings Suppliers

Rod end bearings are articulated bearings with or equipped with rod ends, which belong to a category of articulated bearings.

Spherical bearings are plain spherical bearings, which are composed of inner and outer rings with spherical contact surfaces. Spherical bearings are mainly composed of an inner ring and an outer ring, which can bear larger loads. According to its different types and structures, it can carry radial load and axial load. It can also take the combined amount of both types of cargo. Due to the composite material inlaid on the outer spherical surface of the inner ring, the bearing can produce self-lubrication during operation. Generally used for low-speed oscillating movements, and can also perform tilting movements within a specific range of angles. When the support shaft and the shaft housing hole have a large concentricity, they can still work usually. Self-lubricating joints are used in water conservancy and professional machinery industries. Because of the large spherical sliding contact area of the spherical plain bearing and the large inclination angle, at the same time, most spherical plain bearings adopt unique processing methods, such as surface phosphating, galvanizing, chrome plating or outer sliding surface lining, inlaying, spraying, etc. Therefore, it has a hefty load capacity and impact resistance, and has the characteristics of corrosion resistance, wear resistance, self-alignment, proper lubrication, or self-lubrication without lubrication pollution, and can usually work even if the installation is misplaced. Therefore, articulated bearings are widely used for low-speed oscillating motion, tilting motion, and rotary motion.

Typical rod end bearings are swivel rod ends, clevis rod ends, and threaded rod ends.

Spherical plain bearings and rod ends have multiple designs and different combinations of sliding contact surfaces. Standard models are swivel rod ends, clevis rod ends, and threaded rod ends. Each design and combination has unique properties that make it particularly suitable for specific applications.

Rod end bearings (swivel rod ends, clevis rod ends, threaded rod ends) vibration is very sensitive to the damage of rod end joint bearings, such as peeling, indentation, rust, crack, wear, etc. will be reflected in the rod end joint bearing vibration measurement, Therefore, by using a particular rod-end articulated bearing vibration measuring device (frequency analyzer, etc.), the magnitude of vibration can be measured, and the specific situation of the abnormality cannot be inferred through frequency analysis. The measured values vary depending on the use conditions of the rod-end articulated bearing or the installation position of the sensor. Therefore, it is necessary to analyze and compare the measured values of each machine in advance to determine the judgment standard.

The temperature of the rod end bearing (swivel rod ends, clevis rod ends, threaded rod ends) can be inferred from the outside temperature of the rod end spherical plain bearing. More appropriate. Generally, the temperature of the rod end joint bearing gradually rises with the operation of the rod end joint bearing and reaches a steady-state after 1-2 hours. The average temperature of the rod end joint bearing varies with the machine's heat capacity, heat dissipation, speed, and load. If the lubrication and installation parts are suitable, the temperature of the rod end joint bearing will rise sharply, and abnormally high temperatures will occur. At this time, the operation must be stopped, and the necessary precautions must be taken. The use of a thermal sensor can monitor the working temperature of the rod end joint bearing at any time. It can automatically alarm or stop when the temperature exceeds the specified value to prevent a shaft accident.

Pay attention to the following points when installing and removing swivel rod ends, clevis rod ends, threaded rod ends:

1. Where the press is missing or unavailable, the end rod joint bearing can be installed with an assembly sleeve and a small hammer. The hammering force should be evenly transmitted to the entire circumference of the end face of the end rod articulated bearing ring, so the end face of the mounting sleeve should be made spherical.

2. The force required to install the rod end bearing is related to the size of the joint bearing and the amount of interference. For medium-sized or large joint bearings with a substantial obstruction, hot-fitting is commonly used. Put the end rod articulated bearing or detachable articulated bearing ring into the fuel tank or particular heater before heating, and evenly heat it to 80-100 ℃, not more than 100 ℃.

3. Hot-loaded rod end bearings require skilled operating skills. When the rod end bearing is taken out from the heating oil tank or heater, the oil stains and attachments on the surface of the joint bearing surface should be wiped off immediately with a clean cloth (note that cotton yarn cannot be used), and then placed in front of the mating surface in one operation Push the joint bearing against the shoulder of the shaft. During the cooling process, always push tightly, or tap the joint bearing tightly with a small hammer through the assembly sleeve. When installing the end rod joint bearing, the joint bearing should be rotated slightly to avoid the installation from falling or getting stuck.

4. When the outer ring of the rod end bearing and the housing hole are tightly fitted, the housing can be heated and installed into the joint bearing. Especially for light metal joint bearings, during the tight-fitting process, the mating surface may be damaged due to the pressing of the outer ring. In this case, the end rod joint bearing should be heated first.