Although there are many types of self-tapping screws, they all have the following common points: (1) They are generally made of carburized steel (accounting for 99% of the total output). Also available in stainless steel or non-ferrous metals. (2) The product must be heat treated. Carbon steel self-tapping screws must be carburized, and stainless steel self-tapping screws must be solution hardened. In order to make the self-tapping screw meet the mechanical properties and performance required by the standard. (3) The product has high surface hardness and good core toughness. That is, inner softness and outer rigidity. This is a major feature of the performance requirements of self-tapping screws. If the surface hardness is low, it cannot be screwed into the matrix; if the toughness of the core is poor, it will break as soon as it is screwed, and it cannot be used. Therefore, inner soft outer steel is a very important requirement for self-tapping screws to meet the performance requirements. (4) The surface of the product needs surface protection treatment, generally electroplating treatment. The surface of some products must be treated with phosphate (phosphating), such as wallboard self-tapping screws are mostly phosphated. (5) Produced by cold heading process. It is recommended to use high-speed cold heading machine and high-speed thread rolling machine or high-speed planetary thread rolling machine for production. The emphasis here is on high speed to ensure product quality. Only self-tapping screws produced by high-speed machines have well-formed heads and high-quality threads.
The side wall of the bolt hole is threaded, and the top of the nut is provided with several flattening notches. According to the locking nut of the preferred embodiment of Guangdong Yueluo Hardware Industry Co., Ltd., the number of flattening notches is three. Due to the above features, the three flattening notches can be used as the focal point of the tightening tool, and the
The main operation method of the embedded knurled copper nut of the lock nut is injection molding. After heating, it is embedded into the plastic part or directly injection molded. If injection molding is used, the melting point of P/NYLOY/PET is above 200°C. , After the embedded nut is hot melted into the plastic part, the temperature rises rapidly. After injection molding, the plastic body rapidly cools and crystallizes and hardens. If the embedded nut temperature is still at a high temperature, it may fall to the place where the copper nut contacts the plastic part. Start to loosen or crack. Therefore, copper nuts are used instead of carbon steel nuts in the injection molding of embedded nuts.
With the mass production of large-scale equipment, standardization, and the concept of lean production, it has become more and more important to improve the efficiency of the assembly stage. Nowadays, when assembling small equipment, power tools and automatic bolt supply devices are basically popular, but only for M3 and smaller However, large equipment is often fastened with M8 or larger diameter bolts, and it is still in the process of combining manual and air tools. Among them, the pre-installation of the flat and spring washers on the bolts is completely manual operation. When the bolts need to be tightened in large quantities, the shortcomings of low efficiency are particularly obvious, and the flat and spring washers are easy to be scattered when manually assembled, and there are mixed installations of different specifications. Problems such as less installation and missing installation will affect the processing quality.
Ordinary nuts are suitable for use in fixed-load equipment. Ordinary nuts are used to fix on stationary workpieces and cooperate with flat and spring washers to ensure the reliability of the nut. However, on moving workpieces with vibration loads, the equipment may The vibration caused the nut to loosen. As a kind of nut, the slotted nut is used to connect the two mechanical equipment tightly. It is mainly used in the occasions with vibration load or alternating load. It is used in conjunction with the split pin to ensure the nut lock. The reliability of tightening is often used as a lock nut to prevent the main nut from loosening back.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: round washers, national standard square nuts, copper embedded, metal lock nuts and other products, we can provide you with suitable fasteners for you solution.