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Daily maintenance of SKF bearing heater

Update:28-11-2020
Abst:

1) Principle of bearing heater: The principle of Youxin […]

1) Principle of bearing heater: The principle of Youxin series bearing induction heater is to use metal to generate eddy current in the alternating magnetic field to make the bearing itself heat. The principle is that when thicker metal is in the alternating magnetic field generated by the bearing heater, it will be Electromagnetic induction phenomenon generates electric current. For thicker metals, after the bearing heating machine generates current, the current will form a spiral flow path inside the bearing. The heat generated by the current flow is absorbed by the metal itself, which will cause the bearing to quickly heat up and expand to reach interference. Assembly requirements. Generally, bearings are prone to magnetism when using a heater. It is best to choose a bearing hot sleeve machine that integrates heating and demagnetization. The demagnetization of the bearing heater uses the principle of electromagnetics and uses 380V/50HZ AC power to generate positive and negative in the coil Alternating magnetic field to achieve demagnetization effect. Different from other assembly bearing interference assembly methods, many bearings are damaged during the installation process. Improper SKF bearing heating method is one of the important reasons. If heating with welding tools is used, the bearing will be deformed; heating with furnace fire will cause uneven heating on both sides of the bearing; heating with oil bath will pollute the bearing and increase noise due to unclean oil; heating with oven is too time-consuming . As for the knocking installation, the bearing is more susceptible to damage.

 

2) Application of induction heater: series bearing heaters are used for mass induction heating and assembly of circular and cylindrical parts such as bearings, bushings, gears, couplings, diameter rings, etc., so that they can be heated and expanded to meet interference The need for assembly. It is an induction heater that is truly suitable for long-term assembly in production assembly lines and can be adapted to most harsh working environments.

 

3) The advantages of the bearing heating machine are: saving money and electricity by 90%, saving oil by 100%, saving plant area by 70%; saving time: working efficiency is increased by more than 4 times, operators are reduced by 80%; reliable: uniform heating, absolute Cleanliness is conducive to improving the quality of assembly; safety: built-in overheating protection system, no fire hazard; environmental protection: no oil fume pollutes the air, which is conducive to environmental improvement and staff health. Demagnetization: This product can automatically demagnetize during the heating process. The residual magnetism of the bearing after heating is: 2A/CM, which meets the ZQ33-85 standard.

 

Will heating the bearing affect the bearing itself?

Answer: The bearing heating temperature cannot exceed 120 degrees. As long as it is within 120 degrees, the pair of SKF bearings is absolutely safe, because according to the characteristics of bearing steel, after 120 degrees, it will cause bearing clearance and preload changes, slow fit, early damage and other problems.

Of course, the specially heat-treated bearings can heat up to 200 degrees.

 

 

 

2. What effect does bearing heater have on the human body during operation?

Answer: The frequency used by our products is 50 Hz. Like household appliances such as rice cookers, the power frequency is absolutely safe for the human body. It can be said that its impact on the human body is far less than that of a mobile phone.

 

3. What is the maximum inner diameter that can be heated?

Answer: AUELY products use the maximum outer diameter as the rated unit, because different workpieces have the same inner diameter but completely different outer diameters. For example, the inner diameter of a gear is 100mm and the outer diameter reaches 1000mm, so the inner diameter is not comprehensive.

 

4. What is the expansion coefficient of the inner ring?

Answer: There is an attached table for reference

Generally speaking, a bearing with an inner diameter of 100 is heated to 100 degrees and the inner ring expands by 10 wires. (Of course it depends on the actual work piece. The difference in cage material and thickness will affect the expansion coefficient)

 

5. The highest temperature that can be heated?

Answer: AUELY heater has two heating modes: temperature mode and time mode

The maximum temperature that can be set in temperature mode is 250 degrees (except for special specifications), and there is no limit in time mode.

 

6. What if the height of the workpiece we need to heat is not enough?

Answer: If the workpiece is too high and too wide, there are 2 solutions

1.Add a post extension rod, that is, the U-shaped two ends are padded to heat the workpiece.

2. Customization: design-confirmation-trial run-improvement-delivery of finished products

 

7. Is the heated workpiece heated evenly?

Answer: Uniformity is relative, even heating depends on two aspects

1. Bearing: The inner ring is heated uniformly, and there is a large temperature difference with the outer ring, because the heater design is mainly for the inner ring heating, which is also required by the heating sleeve.

2. Workpiece: Asymmetrical shape. Irregular, too high or too long workpieces will affect

 

8. What if I want to heat to 300 degrees

Answer: SKF bearing heater has two modes: time mode and temperature mode

Since the maximum temperature that the temperature measuring probe can withstand is 250 degrees and the highest value of the temperature selection is also 250 degrees, it is necessary to use the time mode to heat more than 250 degrees, and use an external temperature tester to measure (commonly contact and infrared guns)

 

9. About residual magnetism

Answer: In order to prevent bearing residual magnetism from affecting the operation of SKF bearings, AUELY heater sets two demagnetization programs: automatic demagnetization/manual demagnetization

Automatic demagnetization is automatically completed after the heating operation is completed, and manual demagnetization is a special design for workpieces with special requirements for residual magnetism. (The temperature probe should be removed from the workpiece during manual demagnetization)

 

10. About the principle of degaussing

Answer: Because any ferrous material has a hysteresis loop, during the heating process, the current flowing in the workpiece is large, and the hysteresis loop is also large. If the power is suddenly cut off, it may leave a large remanence. By effectively controlling the thyristor, the hysteresis loop is continuously reduced, and then the power supply is cut off, the workpiece will not have remanence.

 

11. Can SKF products be used as degaussers?

Can. However, there are restrictions on the object to be demagnetized, which must be put on the heating rod, and there is a short heating process during the demagnetization process.

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