Now many bearings are inferior, what does that mean? That is to say, unqualified bearings, no die guide sleeve to meet the application specifications, the main reason is that the inspection of the factory is not strict, so that bearings become inferior products, such bearings assume that we use them, then such bearings will generally be damaged within a few days, or simply can not be used, in operation will also lead to mechanical damage, so that Bearings rolled in this way do not conform to the specifications must not be used, you know? Never use such bearings. We should use bearings, the best is to use imported bearings products, because imported bearings enterprises test more rigorously, generally will not present quality problems, of course, there are oil bearing exceptions, to completely avoid us to buy bearings that do not meet the specifications, then we should learn to distinguish the good and bad of bearings. Let's introduce some common sense in this respect.
In the selection of bearings, we first investigate the appearance of bearings, which can be judged by the appearance of bearings whether it conforms to the specifications. Bearing appearance inspection should be carried out under astigmatism lamp, and the bearing appearance, cracks and other parts should be carefully investigated. Now let's explain the specific method. This method is not only applicable to imported bearings, but also can judge whether the imported bearings of other brands conform to the specifications.
1. Various kinds of cracks, such as original data cracks, forging cracks, heat treatment cracks and grinding cracks, will become the source of stress convergence and rapid expansion in the future bearing operation process, forming bearing cracks, which will have a great impact on bearing life and operation safety.
2. Corrosion, black skin and pitting, the latter two are the shortcomings of simple storage of water and dirt, the simplest development into corrosion. Corrosion is the source of pollution that leads to poor installation, early wear and fatigue. Serious corrosion will make bearings useless.
3. Peeling and folding, the two shortcomings are not well combined with the base metal, and there are decarbonization or carbon depletion around them to varying degrees. The data are simple collapse, concave or abrasion, which is not conducive to the life and accuracy of bearings.
4. All kinds of mechanical scars, such as abrasion, scratch, crush, bruise, etc., will result in poor installation of bearings, resulting in eccentric load and stress convergence, resulting in the decline of rotational accuracy and service life.
5. The quality of riveting or welding of cage should be investigated firstly whether the rivet head is offset, inclined, slack, lack of meat or "double eyelids", whether the welding direction is correct, whether the weld joint is too large or too small, whether the welding is not strong or whether the welding is excessive, which causes the phenomenon of stuck and roll.
6. Others, such as poor typing quality, such as blurred handwriting and damaged handwriting, should be considered inferior, and severe ones may not be tested.