Service HotlineAlthough 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.
At present, in the process of injection molding, stamping, testing, etc., the product is usually positioned on the mounting plate or the positioning plate by pins. The general pin positioning method uses cylindrical pins with the same cross-sectional diameter for positioning. Because the product is easily deformed during processing, the pin positioning hole on the product is also deformed. With this kind of pin for positioning, the pin is often stuck. Dead products cause inconvenience in handling the workpiece, resulting in broken pins or scratched or even damaged products, with obvious defects.
spring washer is installed under the nut to prevent the nut from loosening. It is stated in the national standard. Hexagonal slotted nuts are specially designed for use with bolts with holes at the end of the screw, so that the cotter pin can be inserted into the hole of the screw from the groove of the nut to prevent the nut from automatically loosening. It is mainly used for vibration loads or alternating loads. . The methods to prevent the nut (or bolt) from automatically loosening in the mechanical design and production are as follows: 1. Add a spring washer; (simple and easy to do) 2. Use a hexagonal slotted nut + a split pin; (increase the processing process) 3 . Pad the stop washer; (increase the processing process compared with the same period of last year) 4. Insert the steel wire into the hexagon head opening of the hexagon bolt. (Increased processing steps compared to the same period of last year) Spring washers are used to prevent loosening. For example, the bolts connecting the motor and the machine base generally need to add spring washers, because the motor vibrates without the spring washers, and the nuts will loosen. Generally, the fasteners on the equipment with vibration There is a spring gasket on it, and there is generally no need to add a gasket on the flange! Whether the spring gasket is added to the flange is related to the medium circulating in the pipeline. If it is easy to generate pulses, it is best to add spring gaskets, as well as high-speed fluid, and the caliber changes frequently. Do not generalize. On some valves, the stuffing box gland All flanges need to be added with spring gaskets. The automatic selection of spring gaskets is included.
In actual use, the rivet rod body 3-2 is passed through the riveting plate 6 and the riveting plate 7, and the rivet dome head 3-1 is placed in the mold cavity 1-1, and the cover mold 2 is driven by the riveting machine to impact the rivet rod body 3-2. Because the center of the cover mold 2 is provided with a cavity 2-1 that matches the shape of the rivet dome 3-3, the end of the rivet rod 3-2 will form the rivet dome 3-3. However, due to the rivet When the riveting machine is impacted and vibrated, a large amount of oxide slag 4 will be generated, and the oxide slag 4 will slide down the surface of the cavity 1-1 to the bottom of the cavity 1-1 and accumulate. At this time, the temperature of the rivet is very high and the plasticity is very good. The hardness is extremely low and it is easy to form. Therefore, the accumulated oxide slag 4 squeezes the surface of the rivet dome 3-1 and the bottom surface of the cavity 1-1 to form pits, and causes wear on the bottom surface of the cavity, not only It affects the riveting quality, riveting strength and appearance quality of the rivet, and also affects the quality of the rivet die, resulting in economic losses.
Basic requirements for the installation of T-bolt sleeve components: only when the T-head and the middle slot of the anchoring plate are in good agreement and the anchoring surfaces are in close contact, can the force be evenly applied. If the T-head and the anchoring plate are in line contact, even only point contact , the bolt is partially stressed, which will seriously affect the life. Therefore, the verticality of the sleeve installation must be less than or equal to 1/1000, that is, the horizontality of the anchoring plate surface must be less than or equal to 1/1000, and the center deviation of the sleeve must be controlled within 5mm (the center deviation of the T-bolt is 2mm). Therefore, improving the embedded accuracy of the T-bolt sleeve is the key to the installation of the T-bolt integral sleeve.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: aluminum alloy screws, thick and thin washer mesons, open round head rivets, support columns and long copper nut columns and other products, we can provide you with suitable products Your fastener solution.
