1. Whether the outer packaging is clear: under ordinary circumstances, the brands of the main factory have their own special presets, and the people in charge of the post implement the presets for the outer packaging. Moreover, the factories with qualified production conditions are arranged for manufacturing production,
because the packaging is very clear and unambiguous from line Techniques For to color block. Whether the steel seal words are clear: brand words, labels, etc. will be printed on the NTN bearing body. The font is very small, but most of the products produced by the factory use steel printing technology,
and press the word before passing the heat treatment, because the font is small, but it is deeply Techniques For concave and very clear. The font of counterfeit products is not only faint, because the printing technology is not delicate, and the font floats on the surface, which can even be erased by hand.
2. Whether there is any noise: hold the inner sleeve of NTN bearing with your left hand, turn the outer sleeve with your right head to Techniques For make it rotate, and listen to whether there is any noise. Because the production conditions of most counterfeit products lag behind and are absolutely operated by hand,
it is difficult to avoid mixing impurities such as sand in the production process and hiding them in the bearing body, so they will emit noise at the moment of rotation. This is a big difference from the factory brands that Techniques For strictly implement production standards and operate with machines.
Whether there is muddy oil on the surface: this should be taken care when purchasing NTN bearings. Because up to now, the antirust technology in China is still 3 It’s not especially at home, so it’s easy to leave thick traces of oil when Techniques For carrying out antirust treatment on the bearing body.
When holding it in the grip, it’s sticky and thick. However, the remnants of antirust oil can hardly be seen on the overseas original bearings. In particular, the expert with careful care said that NTN bearings smell like a smell. It must be under antirust oil, but it’s just invisible. Whether the chamfering is even: the chamfering of the bearing, that is,
the cross seam between the horizontal and vertical surfaces, imitates and pretends the bearing. Due to the limitation of production technology, the disposal of these corners is not satisfactory.
In order to maintain the original performance of NTN bearing in good condition for as long as possible, it is necessary to maintain and repair in order to prevent accidents, ensure the Techniques For reliability of operation and improve productivity and economy.
Maintain the operation standard of corresponding mechanical operation conditions and carry out it regularly. The contents include monitoring the operation status, replenishing or changing the lubricant, and regular disassembly inspection. As maintenance items in operation, there are bearing rotation sound, vibration, temperature, lubricant state, etc.
first record the appearance of the bearing, confirm the residual Techniques For amount of lubricant, and wash the bearing after sampling the lubricant for inspection. As a cleaning agent, gasoline and kerosene are commonly used. The cleaning of removed NTN bearings is divided into coarse cleaning and fine cleaning.
They are placed in the container respectively. First, put the metal mesh bottom so that the NTN Techniques For bearings do not directly contact the dirt of the container. During rough cleaning, if the bearing rotates with dirt, it will damage the rolling surface of the bearing, which should be paid attention to. In the coarse cleaning oil,
use a brush to remove the grease and adhesion. After it is roughly clean, turn to fine cleaning. Fine cleaning is to carefully clean the bearing while rotating in the cleaning oil. In addition, the cleaning oil should always be kept clean.
Maintenance and judgment of NTN bearing: in order to judge Techniques For whether the disassembled bearing can be used, the bearing shall be cleaned and checked. Check the state of raceway surface, rolling surface and mating surface, the wear of cage,
the increase of NTN bearing clearance and the damage of irrelevant dimensional accuracy. It is abnormal. For non separable small ball bearings, support the inner ring horizontally with one hand and rotate the outer ring to confirm whether it is smooth.
Tapered roller bearings and other separable bearings can inspect the raceway surfaces of rolling elements and outer rings respectively.
Since large bearings cannot be rotated by hand, pay attention to the appearance of rolling elements, raceway surfaces, cages, edge retaining surfaces, etc. the higher the importance of bearings, the more careful the inspection is.