Views:6 Author:Site Editor Publish Time: 2020-05-16 Origin:Site
The bearing is an important component in mechanical equipment. Its main function is to support the mechanical rotating body, reduce the friction coefficient during its movement, and ensure its turning accuracy. There are many kinds of bearings, such as spherical plain bearings, rod end joint bearing, etc. In the production and processing, once the fake and inferior bearings are used, the consequences will not only lead to machine maintenance and downtime, causing millions of losses, or even lead to casualties.
When there is a problem with the quality of the metal bearing, many people will say that the bearing is refurbished. Here, the refurbishment refers to used bearings that cannot be repaired anymore. There are two sources of so-called pirated bearings:
1) One is the used bearings that are recovered
This situation is divided into many types. The main situations are: stainless steel ball bearings refurbishment after disassembling large-scale eliminated equipment, and used bearings at low prices after regular maintenance.
This type of metal bearing is generally used, the inner and outer rings and end faces are scratched, and the internal rollers, raceways and retainers have been worn. Some illegal retailers will recycle them at a low price and refurbish them.
The main refurbishment measures include:
The ball bearings with small miniature deep groove are cleaned, super finely ground, oil changed, and seals or dust caps are repackaged for sale.
Large stainless steel ball bearings are treated differently according to the wear and tear conditions, mainly finely grinding the inner and outer ring, finely grinding roller and doing acid treatment for the retainer (Corroding externally oxidized copper for a more beautiful appearance) or replacing parts. This kind of spherical plain bearing can't meet the requirements of normal bearing tolerance and rotation accuracy, so it will have a greater impact on customers' use when conducting secondary sales. Due to the small quantity and multi style, it is mostly retailed.
2) Another is to recycle large quantities of unused bearings
This includes many imported steel ball bearings and domestic bearings, of which mainly well-known brands. Generally speaking, the enterprises that deal with such large-scale bearings are local pillar enterprises, mainly due to products backlogs caused by various reasons such as old inventory backlog, conversion or closure. Because there are a large number of single models, they are mostly based on wholesale sales, and the main sales channels are peer transfers or secondary sales.
In general, this type of spherical plain bearing products, except for bearings with grease-bearing, has a certain impact on the quality.
1) The size of the refurbished bearing has changed. The outside diameter is small and the inside diameter is large, which can be measured with a ruler.
2) Check whether the industrial bearing surface accuracy is smooth. Refurbished bearings are rough.
3) Rotate the steel ball bearings by hand. The bearings are rotated unevenly.
4) Look at the gap between the cage and the rolling element. The clearance of the refurbished bearing is larger than the normal clearance.
5) Look at the bead, the beads of refurbished bearings vary in size and has deformation.
6) Look at the slide, the slide of refurbished industrial bearings has irregular wear and deformation.