Fasteners are a class of mechanical parts used for fastening connections and used in a wide range of applications. Fasteners, the use of a wide range of industries, including energy, electronics, electrical, mechanical, chemical, metallurgical, mold, hydraulic and other industries, in a variety of machinery, equipment, vehicles, ships, railroads, bridges, buildings, structures, tools, instruments, chemicals, instruments and supplies, etc., can see a wide variety of fasteners, is a more widely used mechanical foundation parts. It is characterized by a wide variety of specifications, different performance uses, and standardization, serialization, generalization of the degree is also extremely high. Therefore, some people also have a national standard for a class of fasteners called standard fasteners, or simply referred to as standard parts.
Application of fasteners
In a variety of machinery, equipment, vehicles, ships, railroads, bridges, buildings, structures, tools, instruments, meters and supplies, etc., can see a variety of fasteners. It is characterized by a wide variety of specifications, different performance uses, and standardization, serialization, generalization of the species degree is also extremely high. Therefore, some people also have a national standard for a class of fasteners called standard fasteners, or simply referred to as standard parts.
Fasteners are widely used in the mechanical foundation parts. With China's accession to the WTO in 2001 and step into the ranks of international trade powers. China's fastener products are exported to a large number of countries around the world, and fastener products from all over the world continue to pour into the Chinese market. Fasteners as one of the products with large import and export volume in China, to achieve international convergence, to promote Chinese fastener enterprises to the world, to promote fastener enterprises to fully participate in international cooperation and competition, are with important practical and strategic significance. As each specific fastener product specifications, dimensions, tolerances, weight, performance, surface conditions, marking methods, as well as acceptance inspection, signs and packaging and other items of specific requirements.
Commonly used testing instruments
The most important aspect of the development and design of fasteners is quality control, and there are several major gates from incoming materials to finished product shipment, which have different inspection methods. First of all, the incoming material is related to the appearance, size, elements, performance, harmful substances testing, etc.; the process is more appearance, size, knocking experiments, forging flow lines; heat treatment is more appearance, hardness, torque, tension, gold and so on; surface treatment is more some hydrogen embrittlement test, plating, salt spray, etc., including the shipment of a harmful substances testing. In the size, appearance testing, common is the secondary yuan, contour measuring machine, coordinate measuring machine, image sorting machine (this is a full selection machine); mechanical and chemical testing, mainly hardness machine (Rockwell and Vickers), tensile strength machine, metallographic microscope; materials testing, there is a spectral analyzer, salt spray tester.
