Fasteners are a kind of mechanical parts used for fastening connection and are widely used. Fasteners are widely used in a wide range of industries, including energy, electronics, electrical appliances, machinery, chemical industry, metallurgy, mold, hydraulic and so on. In all kinds of machinery, equipment, vehicles, ships, railways, Bridges, buildings, structures, tools, instruments, chemical industry, instrumentation and supplies, you can see all kinds of fasteners, is the most widely used mechanical base parts. It is characterized by a wide variety of specifications, performance and use of different, and the degree of standardization, serialization, universality is also very high. Therefore, some people have the national standard of a class of fasteners called standard fasteners, or simply referred to as standard parts.
Fasteners are a kind of mechanical parts which are widely used for fastening connections. A wide variety of fasteners can be seen on all kinds of machinery, equipment, vehicles, ships, railways, Bridges, buildings, structures, tools, instruments, meters and supplies.
It is characterized by a wide variety of specifications, different performance uses, and standardization, serialization, universality of the species degree is also very high. Therefore, some people have the national standard of a class of fasteners called standard fasteners, or simply referred to as standard parts.
Fasteners are the most widely used mechanical base parts. Along with our country joined WTO in 2001 and entered international trading big country cavalcade. A large number of our fastener products are exported to all countries in the world, and the fastener products from all countries are constantly pouring into the Chinese market.
As one of the products with large import and export volume in China, fasteners are of great practical and strategic significance for promoting Chinese fastener enterprises to go to the world and promoting fastener enterprises to participate in international cooperation and competition. Due to the specifications, dimensions, tolerances, weight, performance, surface conditions, marking methods of each specific fastener product, as well as the specific requirements of acceptance inspection, marking and packaging items.
The most important link in the development and design of fasteners is quality control. There are several key points from the incoming product to the finished product delivery, and these key points have different inspection methods. First of all, the feed is related to appearance, size, elements, performance, harmful substance detection and so on; The process is more about appearance, size, percussion experiment, forging streamline; Heat treatment is more about appearance, hardness, torque, tension, metallography and so on; Surface treatment is more about some hydrogen embrittlement test, coating, salt spray, etc., including shipment has a hazardous substance detection. In size and appearance detection, common are quadratic, contour measuring instrument, CMM, image sorting machine (this is a full selector); Mechanical and chemical testing, the main hardness machine (Lowe and Vickers), tensile machine, metallographic microscope; Material testing, there is a spectrum analyzer, salt spray testing machine.
It usually includes the following 12 types of 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 fastener is locked, the pressure and heat generated between the teeth will destroy the oxide layer, causing the metal threads to block or shear, and then the phenomenon of adhesion. When this occurs continuously, the stainless steel fastener will lock completely and cannot be removed or relocked. Usually, this series of blocking _ cutting _ adhesive _ locking action takes place in just a few seconds, so the correct understanding of the use of this type of fastener can prevent this phenomenon.
Stainless steel fastener product size standards: specify the content of the basic size of the product. Product with thread.
No standards in terms of product technical conditions. Specifically, it also includes the following standards:
Standards for tolerances of fastener products: Specify tolerances of product size and form and position.
Standards for mechanical properties of fastener products: specify the marking method of mechanical properties grade of products and the content of mechanical properties items and requirements; Some fastener products will change this content to product material performance or work performance.
Standards for surface defects of fastener products: specify the types of surface defects and specific requirements of products.
The standard for surface treatment of fastener products: specify the type and specific requirements of surface treatment of products.
Fastener product test standards: specify the above performance requirements of the test content.
Standards for acceptance inspection, marking, and packaging of stainless steel fasteners.
The standard for marking method of fastener products: specify the content of the complete marking method and simplified marking method of the product.
Other standards for stainless steel fasteners, such as fastener terminology standards, fastener product weight standards, etc.
The machinery industry is one of the main users of fasteners. Due to the late recognition of the important position of mechanical foundation parts in the machinery industry in China, the long-term lack of investment resulted in the poor foundation of the whole industry, a thin foundation, and weak strength.
Especially with the improvement of China’s main engine level, the bottleneck phenomenon of mechanical base parts lagging behind the main engine is increasingly apparent. Today, although in the technology introduction, technological transformation, scientific research, and development, the state has given a certain amount of support, compared with the current market demand and foreign level, there is still a large gap, in specific performance in product varieties, low level, unstable quality, the early failure rate is high, poor reliability.
Fasteners as the main basic parts of the mechanical industry, and the development of the mechanical industry, also put forward higher requirements for fastener products. Domestic standard fasteners have been in oversupply, and high-grade fasteners (high temperature, special shape, titanium plastic composite, special performance fasteners) are in short supply, but also rely on imports. The National Machinery Administration lists “standard fasteners” as restricted products and “high strength deformed fasteners” as currently encouraged products. With the improvement of the national industrialization level and technical progress, the use of high-strength fasteners is gradually increasing.
Please feel free to fill out the form below and we will contact you shortly.
Easiahome provides worldwide distribution of all stainless steel. With our wide range of products, we offer expert market advice and complete metal working.