First, the performance and characteristics of the spindle bearing:
As a special bearing for textiles, the spindle bearing has a special structure. It adopts a single-row radial short cylindrical roller structure without inner ring and is a high-speed precision bearing that bears pure radial load. The assembled integral bearing is still open. Considering the assembly, packaging, transportation and user reassembly requirements, the current spindle bearings mainly use a special anti-rust oil. It not only has good anti-rust performance, but also ensures that the bearing is not prone to scatter when entering the final user assembly.
Due to the single-row radial short-circle roller, the series of bearings are rigid and bear large radial load; high manufacturing precision, flexible rotation, stable, low noise, suitable for high-speed operation; simple structure, low power consumption; convenient maintenance . At present, the implementation standard of the spindle bearing series products is still: FZ/T92025-1994 "DZ series spindle bearing" textile industry standard.
The cage with the new reinforced nylon material has the following performance characteristics: First, the new cage adopts engineering plastics - PA66 glass fiber reinforced nylon material; second, it adopts injection molding processing method, the cage has good craftsmanship, size and shape. The stability is also good; the third is the cage with nylon material has a certain self-lubricating effect; the fourth is to optimize the design of the pocket structure, so that the swing amplitude of the roller during high-speed operation is reduced, thus To a lesser extent, noise.
Second, the correct use of spindle bearings:
1. In the case that the bearing housing bearing hole size, shape, and precision are not good, the bearing will be affected by it and will not exert the best performance. For example, if the dimensional accuracy and shape accuracy of the inner hole of the bearing housing are not good, the outer ring of the bearing will be deformed, resulting in deterioration of the roundness of the inner hole of the bearing; if the accuracy of the shoulder is not good, the outer ring of the bearing and the inclination of the roller will be generated, which will increase the concentration. The load will reduce the bearing fatigue life, and more serious will cause the cage to break and sinter; if the bearing of the inner ring of the bearing is not accurate, such as size, roundness, cylindricity, waviness, roughness, position The accuracy of the other aspects will also obviously lead to an increase in the vibration value of the whole set of spindles.
2. The complete set of bearings has undergone strict precision matching before assembly, so the scattered bearing parts are not interchangeable before use.
3. On the cleaning of spindle bearings and spindles. Due to the compact structure of the spindles, there are many other parts in the spindle cavity, and their cleanliness also affects the cleanliness of the bearing working cavity. Therefore, before the assembly is pre-cleaned with the ingot parts, after the assembly is assembled, the process of cleaning the assembly ingots including the bearings is a more reasonable process.
4. Bearings should not be bumped and impacted during assembly. Bumps and impacts can easily cause collisions between bearing parts, resulting in bearing failure.
5. When the bearing seat is crimped, care should be taken to control the angle and strength of the crimping to avoid the deformation of the bearing parts caused by unreasonable curling.
6. For bearings that have exceeded the anti-rust period or long storage time, rust may occur or the roller may stick due to dryness of the anti-rust oil.
Third, the correct maintenance and maintenance methods for bearings:
1. First of all, when the spindle bearing in the spindle is in operation, it is necessary to fully guarantee the lubrication, and the lubricant should be regularly added according to the actual use condition, and the oil cannot be cut off for a long time. Therefore, for the user company, a better and more suitable spindle lubricant should be used. The new special spindle oil can significantly improve the lubrication performance, extend the oil change interval, extend the service life of the spindle and the bearing, and also has better anti-rust and anti-corrosion properties.
2. Secondly, the bearing with reinforced nylon material cage should be used at a temperature lower than 120 °C.
3. In addition, the spindle should be cleaned and cleaned to prevent damage and scratch the surface of the roller. To remove the residue of the bearing part as much as possible, it is better to rinse and suck the inside of the ingot to clean the residual oil. Care should be taken to avoid the use of the dumping type to cause the accumulation of cleaning waste to remain in the bearing parts, resulting in problems such as noise and wear failure of the bearings.
2018年11月30日星期五
2018年11月28日星期三
Failure Analysis of Cracking of Outer Ring of Tapered Roller Bearing Made of Carburized Steel
1. Outer ring cracking macroscopic features
In addition to a through crack that is parallel to the axis, the outer surface of the outer ring of the carbonized steel tapered roller bearing has two scattering cracks originating from the large crack. In addition to the two ends and the middle non-working area, there are two large wear zones on the ferrule, which have different bright white gloss bands. A number of "scale"-shaped small straight cracks are distributed from the edge of the wear zone about 20 mm from the end face, and the direction is parallel with the large crack. The longest is about 40 mm, and most of them are 5-10 mm, as shown in Fig. 1 and Fig. 2. These characteristics indicate that the large crack that penetrates is developed by one of these fine cracks.
2. Fracture scanning electron microscopy
The macroscopic characteristics of the fracture of the original large crack of the outer ring are shown in Fig. 3. The brittle fracture feature is exhibited. The fatigue source characteristics can be seen at the fracture corresponding to the "scale" crack zone on the outer surface of the outer ring fracture, as shown in Fig. 4. According to this, it can be judged that the crack of the ferrule is fatigue and brittle fracture.
Scanning electron microscopy revealed that the fatigue source region is located in the white bright band on the outer surface of the ferrule. As shown in Fig. 5 and Fig. 6, it can be seen from the fracture structure of different magnification that the white bright region is located on the surface of the carburized and quenched layer. That is, near the outer surface of the ferrule. The cracking of the carburized quenching layer below the fatigue zone is characterized by cleavage cracking, as shown in Fig. 7, indicating that a one-time rapid fracture occurs shortly after fatigue cracking. The fracture structure of the ferrule core is mainly due to the dimple, which is caused by the soft slat martensite structure of the heart, as shown in Fig. 8.
A large number of small cracks on the outer surface of the outer ring are finely cracked. The details under scanning electron microscopy are shown in Fig. 9. It can be seen that these small cracks are parallel to the main crack that penetrates, and are completely perpendicular to the wear direction on the outer ring surface. The microhardness comparison test of the wear zone of the metallographic sample made in parallel with the small cracking found that the hardness value of the section at a depth of about 0.1 mm below the wear zone was higher than that of the carburized quenched layer (see Figure 10). This indicates that the wear zone on the outer surface of the ferrule has a hardening phenomenon. The hardness of the wear hardened layer is 923 HV and 941 HV, and the hardness of the carburized and quenched layer is 730 HV and 719 HV.
3. Metallographic examination
The outer surface wear area has a layer of corrosion-resistant white light with a thickness of about 0.05 mm. Under the white light area is a normal carburized and quenched layer, that is, fine needle-shaped martensite structure (see Figure 11). The core of the ring is lath-like. Quenched martensite structure (see Figure 12).
4. Chemical composition analysis
The energy spectrum analysis is shown in Figure 13. The composition analysis is shown in the attached table. Both the energy spectrum and the chemical analysis indicate that the chemical composition of the ferrule material meets the requirements of the G20CrNi2Mo standard.
5 Conclusion
(1) The chemical composition of the cracking ferrule material, the carburizing heat treatment process and the metallographic structure are normal.
(2) The cracking of the ferrule is a brittle fracture caused by fatigue, and the fatigue source is located in the friction damage hardening zone on the outer surface of the ferrule.
(3) The surface of the bearing has grinding burn or secondary hardening during the grinding process. The bearing has an eccentric sliding wear phenomenon in the running outer ring, which causes the outer ring of the bearing to harden and crack in the friction damage zone. At the same time, the ferrule is subjected to a large pressure, and a large alternating tensile stress is generated in the direction around the ferrule, which promotes the fine cracking of the surface of the wear zone and causes the fatigue source to sprout, and finally causes the ferrule to penetrate and crack.
In addition to a through crack that is parallel to the axis, the outer surface of the outer ring of the carbonized steel tapered roller bearing has two scattering cracks originating from the large crack. In addition to the two ends and the middle non-working area, there are two large wear zones on the ferrule, which have different bright white gloss bands. A number of "scale"-shaped small straight cracks are distributed from the edge of the wear zone about 20 mm from the end face, and the direction is parallel with the large crack. The longest is about 40 mm, and most of them are 5-10 mm, as shown in Fig. 1 and Fig. 2. These characteristics indicate that the large crack that penetrates is developed by one of these fine cracks.
2. Fracture scanning electron microscopy
The macroscopic characteristics of the fracture of the original large crack of the outer ring are shown in Fig. 3. The brittle fracture feature is exhibited. The fatigue source characteristics can be seen at the fracture corresponding to the "scale" crack zone on the outer surface of the outer ring fracture, as shown in Fig. 4. According to this, it can be judged that the crack of the ferrule is fatigue and brittle fracture.
Scanning electron microscopy revealed that the fatigue source region is located in the white bright band on the outer surface of the ferrule. As shown in Fig. 5 and Fig. 6, it can be seen from the fracture structure of different magnification that the white bright region is located on the surface of the carburized and quenched layer. That is, near the outer surface of the ferrule. The cracking of the carburized quenching layer below the fatigue zone is characterized by cleavage cracking, as shown in Fig. 7, indicating that a one-time rapid fracture occurs shortly after fatigue cracking. The fracture structure of the ferrule core is mainly due to the dimple, which is caused by the soft slat martensite structure of the heart, as shown in Fig. 8.
A large number of small cracks on the outer surface of the outer ring are finely cracked. The details under scanning electron microscopy are shown in Fig. 9. It can be seen that these small cracks are parallel to the main crack that penetrates, and are completely perpendicular to the wear direction on the outer ring surface. The microhardness comparison test of the wear zone of the metallographic sample made in parallel with the small cracking found that the hardness value of the section at a depth of about 0.1 mm below the wear zone was higher than that of the carburized quenched layer (see Figure 10). This indicates that the wear zone on the outer surface of the ferrule has a hardening phenomenon. The hardness of the wear hardened layer is 923 HV and 941 HV, and the hardness of the carburized and quenched layer is 730 HV and 719 HV.
3. Metallographic examination
The outer surface wear area has a layer of corrosion-resistant white light with a thickness of about 0.05 mm. Under the white light area is a normal carburized and quenched layer, that is, fine needle-shaped martensite structure (see Figure 11). The core of the ring is lath-like. Quenched martensite structure (see Figure 12).
4. Chemical composition analysis
The energy spectrum analysis is shown in Figure 13. The composition analysis is shown in the attached table. Both the energy spectrum and the chemical analysis indicate that the chemical composition of the ferrule material meets the requirements of the G20CrNi2Mo standard.
5 Conclusion
(1) The chemical composition of the cracking ferrule material, the carburizing heat treatment process and the metallographic structure are normal.
(2) The cracking of the ferrule is a brittle fracture caused by fatigue, and the fatigue source is located in the friction damage hardening zone on the outer surface of the ferrule.
(3) The surface of the bearing has grinding burn or secondary hardening during the grinding process. The bearing has an eccentric sliding wear phenomenon in the running outer ring, which causes the outer ring of the bearing to harden and crack in the friction damage zone. At the same time, the ferrule is subjected to a large pressure, and a large alternating tensile stress is generated in the direction around the ferrule, which promotes the fine cracking of the surface of the wear zone and causes the fatigue source to sprout, and finally causes the ferrule to penetrate and crack.
2018年11月26日星期一
Application Research of Metal Materials and Heat Treatment Technology
Abstract: Since the reform and opening up, with the continuous development of modern science and technology, the secondary industry has made rapid progress. The manufacture of machinery is the basis for the development of the secondary industry, and metal materials are essential in the process of mechanical production. The heat treatment technology of metal materials is becoming more and more widely used. The heat treatment technology of metal materials can greatly enhance the processing properties and performance of metal materials and ensure the quality of metal materials. However, there are still some problems in the heat treatment technology of metal materials. The application status of metal material heat treatment technology in China is analyzed, and the suggestions for the problems appearing in it are proposed.
Key words: metal materials; heat treatment; application technology
Foreword
Metal materials are a general term for materials with metallic properties. They generally refer to pure metals or alloys in industrial applications. The main components are metal elements or materials mainly composed of metal elements, including ferrous metals, special metals, non-ferrous metals, and the like. Heat treatment is a metal material thermal processing process. In the solid state, the metal material changes the surface and internal chemical composition and structure of the material by heating, heat preservation and cooling, so that the metal material obtains the required performance. This research focuses on the status quo of professional equipment, operation implementation, energy conservation and environmental protection in the application of metal materials and heat treatment technology, and proposes solutions to problems.
1. Application status of metal materials and heat treatment technology
1.1 Status of professional equipment for metal materials and heat treatment technology applications
With the prosperity of the modern economy and the continuous development of science and technology, China's industrial development has advanced by leaps and bounds, and the machinery manufacturing industry has made tremendous progress. In the process of mechanical manufacturing, metal material heat treatment technology is in an unprecedented stage of rapid development. The professional equipment for heat treatment of metal materials is mainly equipment for annealing, tempering, quenching, heating and other heat treatment processes of metal materials. Most of the equipment works on the principle that when a current flows into the heating coil, a strong magnetic flux whose polarity changes instantaneously is generated in the coil, and the metal material is placed in the coil, and the magnetic flux penetrates the metal material, and the inside thereof is opposite to the heating current. Generate corresponding eddy currents. Since the metal material itself has electrical resistance, a lot of Joule heat is generated, and the temperature of the metal material rises rapidly. At present, most of the metal material heat treatment enterprises use equipment that is relatively backward, and there is a problem of professional equipment being worn out.
Key words: metal materials; heat treatment; application technology
Foreword
Metal materials are a general term for materials with metallic properties. They generally refer to pure metals or alloys in industrial applications. The main components are metal elements or materials mainly composed of metal elements, including ferrous metals, special metals, non-ferrous metals, and the like. Heat treatment is a metal material thermal processing process. In the solid state, the metal material changes the surface and internal chemical composition and structure of the material by heating, heat preservation and cooling, so that the metal material obtains the required performance. This research focuses on the status quo of professional equipment, operation implementation, energy conservation and environmental protection in the application of metal materials and heat treatment technology, and proposes solutions to problems.
1. Application status of metal materials and heat treatment technology
1.1 Status of professional equipment for metal materials and heat treatment technology applications
With the prosperity of the modern economy and the continuous development of science and technology, China's industrial development has advanced by leaps and bounds, and the machinery manufacturing industry has made tremendous progress. In the process of mechanical manufacturing, metal material heat treatment technology is in an unprecedented stage of rapid development. The professional equipment for heat treatment of metal materials is mainly equipment for annealing, tempering, quenching, heating and other heat treatment processes of metal materials. Most of the equipment works on the principle that when a current flows into the heating coil, a strong magnetic flux whose polarity changes instantaneously is generated in the coil, and the metal material is placed in the coil, and the magnetic flux penetrates the metal material, and the inside thereof is opposite to the heating current. Generate corresponding eddy currents. Since the metal material itself has electrical resistance, a lot of Joule heat is generated, and the temperature of the metal material rises rapidly. At present, most of the metal material heat treatment enterprises use equipment that is relatively backward, and there is a problem of professional equipment being worn out.
2018年11月2日星期五
TIMKEN Tapered Roller Bearings 07000/17000/L44600 Series
TIMKEN Tapered Roller Bearings 07000/17000/L44600 Series
07098 - 07196
|
07000
|
24.981 mm0.9835 in
|
50.005 mm1.9687 in
|
14.260 mm0.5614 in
|
9.525 mm0.3750 in
|
13.495 mm0.5313 in
|
07098 - 07210X
|
07000
|
24.981 mm0.9835 in
|
50.8 mm2 in
|
14.260 mm0.5614 in
|
12.700 mm0.5000 in
|
15.011 mm0.5910 in
|
07098 - 07205X
|
07000
|
24.981 mm0.9835 in
|
51.986 mm2.0467 in
|
14.260 mm0.5614 in
|
13.000 mm0.5118 in
|
16.251 mm0.6398 in
|
07098 - 07204
|
07000
|
24.981 mm0.9835 in
|
51.994 mm2.0470 in
|
14.260 mm0.5614 in
|
12.700 mm0.5000 in
|
15.011 mm0.5910 in
|
07098 - 07205
|
07000
|
24.981 mm0.9835 in
|
51.999 mm2.0472 in
|
14.260 mm0.5614 in
|
12.700 mm0.5000 in
|
15.011 mm0.5910 in
|
17098 - 17244A
|
17000
|
24.981 mm0.9835 in
|
61.981 mm2.4402 in
|
16.566 mm0.6522 in
|
14.288 mm0.5625 in
|
16.002 mm0.6300 in
|
17098 - 17244
|
17000
|
24.981 mm0.9835 in
|
61.999 mm2.4409 in
|
16.566 mm0.6522 in
|
14.288 mm0.5625 in
|
16.002 mm0.6300 in
|
07097 - 07196
|
07000
|
25.001 mm0.9843 in
|
50.005 mm1.9687 in
|
14.260 mm0.5614 in
|
9.525 mm0.3750 in
|
13.495 mm0.5313 in
|
07097 - 07210X
|
07000
|
25.001 mm0.9843 in
|
50.8 mm2 in
|
14.260 mm0.5614 in
|
12.700 mm0.5000 in
|
15.011 mm0.5910 in
|
07097 - 07205X
|
07000
|
25.001 mm0.9843 in
|
51.986 mm2.0467 in
|
14.260 mm0.5614 in
|
13.000 mm0.5118 in
|
16.251 mm0.6398 in
|
07097 - 07204
|
07000
|
25.001 mm0.9843 in
|
51.994 mm2.0470 in
|
14.260 mm0.5614 in
|
12.700 mm0.5000 in
|
15.011 mm0.5910 in
|
07097 - 07205
|
07000
|
25.001 mm0.9843 in
|
51.999 mm2.0472 in
|
14.260 mm0.5614 in
|
12.700 mm0.5000 in
|
15.011 mm0.5910 in
|
247 - 244X
|
245
|
25.001 mm0.9843 in
|
61.913 mm2.4375 in
|
18.999 mm0.7480 in
|
17.463 mm0.6875 in
|
21.019 mm0.8275 in
|
17098X - 17244A
|
17000
|
25.001 mm0.9843 in
|
61.981 mm2.4402 in
|
16.566 mm0.6522 in
|
14.288 mm0.5625 in
|
16.002 mm0.6300 in
|
17098X - 17244
|
17000
|
25.001 mm0.9843 in
|
61.999 mm2.4409 in
|
16.566 mm0.6522 in
|
14.288 mm0.5625 in
|
16.002 mm0.6300 in
|
07096 - 07196
|
07000
|
25.159 mm0.9905 in
|
50.005 mm1.9687 in
|
14.260 mm0.5614 in
|
9.525 mm0.3750 in
|
13.495 mm0.5313 in
|
07096 - 07210X
|
07000
|
25.159 mm0.9905 in
|
50.8 mm2 in
|
14.260 mm0.5614 in
|
12.700 mm0.5000 in
|
15.011 mm0.5910 in
|
07096 - 07205X
|
07000
|
25.159 mm0.9905 in
|
51.986 mm2.0467 in
|
14.260 mm0.5614 in
|
13.000 mm0.5118 in
|
16.251 mm0.6398 in
|
07096 - 07204
|
07000
|
25.159 mm0.9905 in
|
51.994 mm2.0470 in
|
14.260 mm0.5614 in
|
12.700 mm0.5000 in
|
15.011 mm0.5910 in
|
07096 - 07205
|
07000
|
25.159 mm0.9905 in
|
51.999 mm2.0472 in
|
14.260 mm0.5614 in
|
12.700 mm0.5000 in
|
15.011 mm0.5910 in
|
07099 - 07204
|
07000
|
25.273 mm0.9950 in
|
51.994 mm2.0470 in
|
14.260 mm0.5614 in
|
12.700 mm0.5000 in
|
15.011 mm0.5910 in
|
07100 - 07196
|
07000
|
25.400 mm1.0000 in
|
50.005 mm1.9687 in
|
14.260 mm0.5614 in
|
9.525 mm0.3750 in
|
13.495 mm0.5313 in
|
07100-S - 07196
|
07000
|
25.400 mm1.0000 in
|
50.005 mm1.9687 in
|
14.260 mm0.5614 in
|
9.525 mm0.3750 in
|
13.495 mm0.5313 in
|
KL44643 - KL44610
|
L44600
|
25.400 mm1.0000 in
|
50.292 mm1.9800 in
|
14.732 mm0.5800 in
|
10.668 mm0.4200 in
|
14.224 mm0.5600 in
|
L44642 - L44610
|
L44600
|
25.400 mm1.0000 in
|
50.292 mm1.9800 in
|
14.732 mm0.5800 in
|
10.668 mm0.4200 in
|
14.224 mm0.5600 in
|
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