A rivet is a part that uses its own deformation or interference to connect the riveted parts in riveting. With the continuous progress and development of science, rivets have been used in many occasions because of their convenient use and reliable connection. The rivet includes a nail head and a stem. The traditional processing mold for the rivet head includes a base, and a nail head forming part is arranged on the base. However, due to the limited service life of the mold, the processing mold of this structure is replaced. It needs to be replaced together with the base, which is a waste of material, which increases the production cost, and the rivet itself is relatively cheap, so this reduces the profit of the enterprise.
Countersunk head screws are mostly used after installation, and the surface of the parts cannot be raised, and the parts to be fastened have two thicknesses. Thickness, after the screw is tightened, there is still a part of the screw thread that does not enter the threaded hole. In this case, the countersunk head screw can definitely be tightened. There is usually a situation where the thickness of the fastened part is less than the height of the head of the countersunk head screw, which is commonly seen in sheet metal parts in mechanical equipment, such as the connection between the hinge of the chassis and the door and the box; the sheet metal of the equipment The connection of the cover to the equipment, etc. Due to the small thickness of the part, the tightened sheet metal part, the screw through hole completely becomes a conical hole, in this case, when the countersunk head screw is tightened, the screw head is not a tapered surface to press the sheet metal part , but the bottom of the screw head and the top of the threaded hole are squeezed. Although it feels that the screw is tightened, the sheet metal part is stuck instead of being pressed. In this case, although it feels that the screw is tightened, the sheet metal The gold pieces were indeed not tightened. This is a very common situation. Let’s talk about the reasons for the processing: the head cone of the countersunk screw has a 90° conical angle, and the apex angle of the newly bought drill is usually 118°-120°. Some workers who lack training do not know this angle is poor. It is often used to ream the hole with a 120° drill bit, which results in that when the countersunk head screw is tightened, it is not the conical surface of the head, but a line at the bottom of the screw head, which is one of the reasons why the so-called countersunk head screw cannot be tightened. , it's not the screw's fault.
Nuts are usually used in conjunction with bolts or screws to fasten other components and are a common and widely used component. In order to make the nut not easy to loosen and fall off when it is subjected to strong vibration and irregular strong toggling, the combined nut has appeared on the market.
For a long time, the rivets used in general riveting, especially the ordinary rivets and bolts and other fasteners commonly used in steel structures such as vehicles and bridges, have low connection reliability, especially under alternating load and impact conditions. Looseness is easy to occur, the maintenance cycle is short, and the maintenance cost is high in the later period, which cannot meet the requirements of railway freight.
Traditionally used for plastic fastening screws, most of the thread designs are self-tapping threads, but for different plastic types, the self-tapping threads also have many different classifications, such as PT profile, Plastite series, Remform profile, etc. The structural parameters and manufacturing process of these threads are inconsistent, or require different main molds and wires. Therefore, to find a plastic screw that is universally applicable to various plastic types, has a single pressing structure, low-cost and simple manufacturing process, especially its special self-tapping thread, is an important issue that needs to be solved urgently at present. question. The purpose of Yueluo Yueluo Guangdong Yueluo Hardware Industry Co., Ltd. is to propose a plastic screw to solve the screw fastening problem that is generally applicable to different plastics. The purpose of Yueluo Guangdong Yueluo Hardware Industry Co., Ltd. is to realize a kind of plastic screw through the following technical scheme, it is characterized in that, the thread of the screw is composed of asymmetric threads with a profile angle of 30°, and the threads are The bottom surface of the connection between them is an arc surface. Yueluo preferably, the asymmetrical thread has a forward thread angle greater than the reverse thread angle, and the sum of the two-direction thread angles is 30°. Yueluo further preferred that the tooth profile angle of the asymmetrical thread is 20 degrees in the direction of installation, and the tooth profile angle in the reverse direction is 12 degrees. Yueluo Guangdong Yueluo Hardware Industry Co., Ltd.'s application of plastic screws, through the improvement of special thread structure, reduces the radial pressure and installation torque when the screw is installed, reduces the damage to the plastic hole; and increases the pull-out resistance of the screw force, it is not easy to appear loose assembly. At the same time, the design of the bottom surface of the connection between the threads of the arc optimizes the flow of the material of the installation object, which improves the integrity of the installation connection.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: enlarged anti-vibration washers, 304 thin hexagon nuts, anti-loose and anti-skid washers, narrow, medium and wide washers and other products, we can provide you with The right fastener solution for you.