Bearing is a common and important part in mechanical equipment, and it is widely used.
In order to earn more money, there are many bad businesses who use old bearings to make good use of them, recycle some used or unused bearings, and then buy them as new bearings after treatment. There is a big difference between these renovated bearings and good bearings, and the service performance is not as good as good bearings. Today, I’d like to share with you the differences between renovated bearings and good bearings, as well as how to identify whether the bearings are renovated bearings when buying bearings.

Differences between refurbished bearing and good bearing:

1. After the renovation, the size of the bearing has changed. The small outer diameter and the large inner diameter can be measured with a ruler.
2. Watch the bearing surface accuracy, whether smooth. The bearing is rough.
3. Turn the bearing by hand to renovate it. The bearing does not rotate evenly.
4. Observe the clearance between cage and rolling element, and the bearing clearance is greater than the normal clearance.
5. Look at the bead grain, bearing bead grain size is different, there will be wear and deformation.
6. Look at the slideway. The bearing slideway has irregular wear and deformation.
7. After the renovation, the size of the bearing has changed. The small outer diameter and the large inner diameter can be measured with a ruler.
8. Watch the bearing surface accuracy, whether smooth. The bearing is rough.
9. Turn the bearing by hand to renovate it. The bearing does not rotate evenly.
10. Observe the clearance between cage and rolling element, and the bearing clearance is greater than the normal clearance.
11. Look at the bead grain, bearing bead grain size is different, there will be wear and deformation.
12. Look at the slideway. The bearing slideway has irregular wear and deformation.

Good ways to identify refurbished bearings:

1. Renovated bearings are generally limited by the technology and equipment of small bearing manufacturers, so the bearing accuracy is low, the bearing surface is rough, the chamfer size is uneven, and some still have black skin and pockmarks.
2. Some inferior bearing materials are ordinary steel, carbon steel, Maanshan Steel and iron pipe. Most of these materials are white in appearance, while the color of special bearing steel is green. But just look at the color can not be completely determined, but also do hardness. The hardness of ordinary steel is low.
3. Some small manufacturers quenching technology is simple, bearing heating uneven, there will be slight deformation.
4. Rotate the bearing to see whether the bearing rotates evenly and whether the sound is continuous without noise.
5. Looking at the cages, the bearing cages of regular manufacturers are regular without burr, and the rivet pier heads of riveted bearing cages are the same size, while the processing technology and equipment of irregular manufacturers are simple, so the cages are rough, and some riveted structure cages are not evenly divided with or offset, and the rivet pier heads are different size or offset.
6. Look at the packaging, the packaging of regular manufacturers is consistent, the font on the packaging is clear, some counterfeit bearing packaging is inconsistent, or simple and irregular.
7. Look at the font on the end face of the bearing, both the steel font and the laser font of the original bearing are very clear and uniform. The laser font has a certain depth, and the counterfeit bearing font has broken marks. The laser font will disappear after being lightly wiped with gauze, while the regular laser font will leave fuzzy font marks after being wiped with gauze.
8. See the certificate, regular manufacturers bearing certificate, and the size of the certificate is the same, most of the certificate paper for oil proof paper. The font is clear, some manufacturers have query information on the certificate, counterfeit certificate, some font is fuzzy, the paper is ordinary paper, the size of the certificate is different. It is suggested to keep a formal manufacturer’s certificate for reference.
9. Some imported bearings are different from domestic ones in terms of antirust oil. Imported bearings are not without antirust agent, but without traces. The surface of bearings is clear, while some counterfeit imported bearings coated with domestic antirust agent feel sticky in the hand, which will taste like antirust oil.
10. Understand and understand the bearing typing specifications of normal products from some regular manufacturers, such as bearing model, trademark and year code. And some false bearing fonts are engraved, even if some fonts are blurred by laser.
11. If there are conditions, it’s better to visit the bearing manufacturer or brand dealer in person.