A kind of screw provided by Yueluo, the rod body of the screw rod has a thread segment, and the two ends of the thread segment are respectively provided with annular and two convex rings. The nominal size of the thread segment, and the distance from the convex ring at the rear end of the screw in the screwing direction to the rod core is greater than the nominal size of the thread segment.
Make further details to make the technical scheme of Guangdong Yueluo Hardware Industry Co., Ltd. easier to understand and master. As shown in Figure 1, Yueluo is a schematic diagram of the thread design structure of the plastic screw of Guangdong Yueluo Hardware Industry Co., Ltd. It can be seen from the figure that this creation mainly controls the tooth angle of the thread. Compared with the normal tooth angle of many self-tapping screws, which are 48 degrees, 60 degrees and 34.5 degrees, the tooth angle of Guangdong Yueluo Hardware Industry Co., Ltd. The profile angle is formed by a 30-degree asymmetrical thread I. In particular, the asymmetrical thread I has a forward thread angle greater than the reverse thread angle. A more preferred embodiment is an asymmetric thread. The tooth profile angle α of the in-line installation is 20 degrees, and the tooth profile angle β of the reverse installation is 10 degrees. With this narrower non-stacked thread, the radial pressure on the plastic material is effectively reduced. In addition, the connecting bottom surface 11 between the screw teeth is designed as a circular arc surface. In the process of forming the self-tapping thread, it is more conducive to the flow of the material and the formation of the thread, and at the same time, the material can be more closely matched with the screw. Moreover, the radial pressure of the casing is relatively uniform, and the formed threads are not easily damaged. Yueluo has been tested by a series of professional parameters. Compared with other traditional screws, the plastic screws designed by Guangdong Yueluo Hardware Industry Co., Ltd. have better radial pressure, shell deformation after installation, load distribution, installation torque, drawing The force distribution, the strength of the pull-out force and the mounting torque range all show advantages. In particular, it can be installed with less torque to achieve the same clamping force and pulling force. Compared with a specific parameter, the thread strength of Delta-PT is 387N, while the thread strength of Guangdong Yueluo Hardware Industry Co., Ltd. reaches 449N. Yueluo can understand the plastic screw structure and implementation of Guangdong Yueluo Hardware Industry Co., Ltd. detailed above. It can be understood that through the improvement of the special thread structure, the radial pressure and installation torque during screw installation are reduced, and the damage to the plastic hole is reduced; And the pull-out resistance of the screw is increased, and it is not easy to appear loose in the 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.
Hot rolled wire rod before plating process - (cold drawing) - spheroidizing (softening) annealing - mechanical dephosphorization - pickling - cold drawing - cold forging - threading - heat treatment - inspection
A T-shaped grounding bolt comprises a connection platform, a hexagonal bolt is welded below the described connection platform, and the lower surface edge of the described connection platform is provided with a barb.
2. Low cycle fatigue Low cycle fatigue means that the fatigue stress is close to or exceeds the yield limit of the material. The material has a certain amount of plastic deformation in each strain cycle. The life is generally in the range of 102 to several times 104, and the fatigue curve is generally used. ε-N curve representation. The finite element calculation results show that after the bolt is screwed into the lock nut, the stress at the root of the threaded piece is large, and part of the surface area is in a yield state, while the strain in the central area of the root of the threaded piece is small, and the strain situation is more complicated. The area with high strain at the root of the thread piece experiences reciprocating loading, which is prone to low cycle fatigue, which reduces the pressure of the thread piece and reduces the screw-out torque.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: GB6172 thin nuts, manhole cover fasteners, hexagon socket head screws, manganese heavy spring washers and other products, we can provide you with suitable products for you. Fastener Solutions.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].