麻花豆星空天美糖心mv-星麻花传媒mv-星空天美梦幻mv免费-天美麻花星空果冻mv-62星空天美梦幻糖心mv-天美电影免费在线观看Now the bolt sales market is mixed, many If the qualification certificate fails to meet the requirements, the manufacturer will crush the reliable companies that meet the qualification certificate to the sales market at a very low price, so that even if these reliable manufacturers sell bolts at the factory price, they will be mistaken by others as cheating customers and making all bolt sales market in the same way Good bolts can not be sold, fake and inferior bolts are full of rampant psychological distortion. According to this, everyone who has been working for 20 years will share some experience on bolt evaluation. Double drum stud will help us identify the quality of bolts, curb the fake and inferior bolts, and maintain the bolt sales market in China!

麻花豆星空天美糖心mv-星麻花传媒mv-星空天美梦幻mv免费-天美麻花星空果冻mv-62星空天美梦幻糖心mv-天美电影免费在线观看Generally speaking, to distinguish the quality of a bolt, we can quickly identify the quality of a bolt only by looking at the screw, screw rod and its wound. First look at the sunshade cap, high-quality bolts of the sunshade cap is generally very uniform, to your visual effect feel very comfortable, light is not enough, also want to take the screw to the table friction, not electroplating process if there is a significant scratch, electroplating process good, if the coating falls down, the head of the head changes Panyu belongs to the fake bolt, this kind of bolt is usually very non rust resistant, the service life is 10 Short. When you look at the sun visor, you can see that the nail rod is also very important. It should not only look straight, but also see whether there are scratches on the top. The scratch indicates that the parts of the equipment are not installed properly under the production and manufacturing conditions. This kind of bolt is not good-looking, and it is harmful to the actual effect. The key point of looking at the nail rod is to see whether it is in the same boat. The nail rod must be seated In the management center of the screws, it is not easy to crack and break the riveting in the case of riveting. Although the wounds look the same, there are many inside University asked, you look at the wound, first to see whether it is leveling, semi hollow rivet wound is more serious, uneven will significantly harm the actual effect of riveting, it is easy to rivet deformation, and just look at the wound is not enough, for the bolt in the center of the half space, also along the wound to see whether the thickness is uniform, if one side is too thick and the other side is too thin, it is difficult to rivet Point to be very careful, look at the bolt as people know, usually some key points can really see a bolt good or bad!