Which industry are fasteners suitable for and how should fasteners be selected

Fasteners are a kind of mechanical parts used for fastening and connecting. Fasteners are widely used in a wide range of industries, including energy, electronics, electrical appliances, machinery, chemical industry, metallurgy, mold, hydraulic and so on. A wide variety of fasteners can be seen in all kinds of machinery, equipment, vehicles, ships, railways, Bridges, buildings, structures, tools, instruments, chemical industry, meters and supplies. They are the most widely used mechanical base parts. It is characterized by a wide variety of specifications, different performance uses, and the degree of standardization, serialization, universality is also extremely high. Therefore, some people have the national standard of a class of fasteners called standard fasteners, or simply referred to as standard parts.

Fasteners include bolts, studs, screws, nuts, washers and pins. Locking or biting often occurs on fasteners made of stainless steel, aluminum alloy and titanium alloy. These metal alloys themselves have anti-corrosion properties. When the surface is damaged, a thin oxide layer is created on the metal surface to prevent further corrosion. When the stainless steel fasteners are locked, the pressure and heat generated between the teeth will destroy the oxide layer, so that the metal thread between the blockage or shear, and then the phenomenon of adhesion. When this occurs continuously, the stainless steel fastener will lock completely and cannot be removed or re-locked. Usually this series of blocking _ cutting _ adhesive _ locking a series of action in just a few seconds, so the correct understanding of the use of this type of fastener, can prevent this phenomenon.

1. Choose the right product

a. Before use, confirm whether the mechanical properties of the product can meet the requirements of use, such as the tensile strength of screws and the guaranteed load of nuts. The length of the screw should be selected appropriately, with 1-2 teeth spacing of the exposed nut after tightening.

b. Before use, check whether the thread is rough and whether there is iron filings or dirt between the threads, which often lead to locking.

c. Before use, fasteners can be lubricated. It is recommended to use butter, molybdenum disulfide, mica, graphite or talc powder for lubrication.

2. Pay attention to the usage method when using

a. The speed and force of screwing should be appropriate, not too fast or too large. Torque wrench or socket wrench should be used as far as possible, and adjustable wrench or electric wrench should be avoided. Too much speed will cause the temperature to rise rapidly and cause locking.

b. In the direction of force, the nut must be screwed perpendicular to the axis of the screw.

c. The use of washers can effectively prevent the problem of overlocking.

Standards for the size of fasteners: specify the content of the basic size of the product; Products with thread also include the basic size of thread, thread end, shoulder distance, back slot and chamfer, end size of external thread parts, etc. 2. Standards for technical conditions of fastener products. Mainly includes product tolerance, mechanical properties, surface defects, surface treatment, product testing standards and the corresponding specific provisions of the content. 3. Standards for acceptance inspection, marking and packaging of screw products: specifically specify the qualified quality level and sampling plan of random inspection items during the acceptance of products leaving the factory, as well as the content of product marking methods and packaging requirements. 4, standard parts, fasteners, screws, screws marking method standard: specify the product complete marking method and simplified marking method. 5, other aspects of fastener standards: such as fastener terminology standards, fastener product weight standards, etc.