The shear strength of a metal material refers to the ability of the material to withstand shearing force, which refers to the strength of the external force perpendicular to the material axis and shearing the material. The test is usually to install the cylindrical pin into the specified fixture, and the gap between the supporting part and the loading part is required to be no more than 0.15mm, and then force is applied to test the shear strength of the material.
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.
The purpose of Guangdong Yueluo Hardware Industry Co., Ltd. is to provide a cement screw that is easy to install and can be removed in view of the shortcomings of the above-mentioned cement nails that cannot be disassembled and the expansion screws are not easy to install for the first time. Guangdong Yueluo Hardware Industry Co., Ltd. is a cement screw, which is realized by the following technical solutions. The cement screw is composed of a nail tip and a nail body. There is a thread at the back of the nail body. This thread can be an internal thread or an external thread. . When using, use a hammer to drive cement screws into the cement, and you can use ordinary screws or nuts to freely screw in and out to install and fix objects. Compared with the existing technology, Guangdong Yueluo Hardware Industry Co., Ltd. has the advantage that there are internal threads or external threads on the back of the cement screw, so it is not only easy to install for the first time, but also the objects to be installed can be disassembled repeatedly. Used as a fastener when installing objects on cement that may need to be dismantled.
Guangdong Yueluo Hardware Industry Co., Ltd. was founded in 1998, and the factory was established in Feilong Industrial Zone, Xiaolan Town, Zhongshan City, Guangdong Province, with an investment of 10 million yuan. The main production is a variety of national standard, non-standard, British, American, metric screws. Mainly include: special screws for the electronics industry (machine screws, self-tapping screws, special screws): nuts (general nuts, flange nuts, external teeth nuts): Washers (external teeth, internal teeth, flat springs) Gaskets, etc.); lathes (precision automatic lathe parts, connecting parts, embedded parts, fasteners, decorative parts, etc.).
The purpose of Guangdong Yueluo Hardware Industry Co., Ltd. is to overcome the above shortcomings and provide a limit screw. The technical scheme of Guangdong Yueluo Hardware Industry Co., Ltd. is realized in the following way. Its structure is composed of screws, hexagonal copper posts and limit necks. The left end of the limit neck is open, the hexagonal copper column is communicated with the inside of the limit neck, and the inside is provided with screw threads. The design length of the screw thread in the hexagonal copper column is 1/3-2/3 of its own length. The advantages of Guangdong Yueluo Hardware Industry Co., Ltd. are (3), which can effectively prevent the problem of poor memory contact caused by the increase of the deformation of the motherboard due to the warping and deformation of the motherboard during installation and fixation, and can effectively control the amount of deformation effect.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: S-type screws, high-tech screws, aluminum alloy coupling long nuts, GB52 national standard ordinary hexagonal carbon steel light nuts and other products, we can provide you with suitable products Your fastener solution.