Service HotlineCommon fastening screws include self-tapping screws, fine-pitch drywall screws, traditional wood screws, and fiberboard screws. The following are the characteristics of commonly used screws, everyone should choose them reasonably. Self-tapping screws The correct application of self-tapping screws should be used for the fastening and connection of metal materials with pre-drilled holes. It has the function of automatically tapping out the internal thread on the metal body, and can complete the thread engagement with it to play a tightening role. However, due to its high thread bottom diameter, when it is used in wood products, the cut into the wood will be shallower; and because the thread pitch is small, there is less wood structure between every two threads. Therefore, it is unreliable and unsafe to use self-tapping screws for wood mountings, especially loose wood. Drywall Screws The proper use of fine-pitch drywall screws is for fastening and joining between metal studs and plasterboard. It suffers from similar drawbacks as self-tapping screws when used on wood mountings. Moreover, due to the large diameter of the head of the dry-wall screw, the embedding of the head is poor, and it is easy to cause unevenness between the head of the screw and the surface of the mounting part after installation. Traditional wood screws Before using traditional wood screws, pre-drilling holes are required on the wooden mounting parts, otherwise it is easy to cause wood cracking. In addition, since the traditional wood screws are not heat-treated, the use of electric tools can easily cause the groove shape to be damaged, and manual installation is very laborious. Fiberboard screws are relatively new types of wood screws, suitable for power tool installation. However, due to its relatively simple thread design, it still cannot effectively solve the stubborn problem of easy cracking when used on hardwood, and it does not have any advantages in screwing speed and screwing torque. [2]
Combination bolts refer to a bolt with a spring washer and a flat washer, which are combined by rubbing teeth. Before the combination bolt is used, the bolt, the spring washer and the flat washer are generally combined by a specific machine. The combined production line mainly includes the processes of feeding, discharging, feeding, charging, screwing and tightening. The existing combined bolt production equipment mainly transmits the bolts to each process through the conveyor belt, and finally completes the combined assembly. The machines in each process are scattered and the space is occupied. The vibrating plate feeding generally puts the bolt head up, and its bolts, spring washers, etc. After the flat pad is assembled, the fixation is poor, and it is easy to fall off during the assembly process.
Specification Model Screw Specification Model Example: 4 X 10 PW AHC (+) ① ② ③ ④ ⑤ ⑥ ⑦ ① Screw Diameter ② Screw Length ③ Screw Head Type B: Spherical Cylindrical; C: Cylindrical; F (K): Countersunk ; H: Hexagon head; HW: Hexagon head with washer; O: Half countersunk head; P: Plain head; R: Half head; PW: Plain head with washer; T: Large flat head; V: Mushroom head;
In the mechanical structure, the existing seals are used on the end face of the bolt or the end face of the oil joint. The copper washer is often used as the seal, and the copper washer can only be used once, and it will become hard after the second use, reducing its sealing performance. Especially when it is used on the oil drain bolt (also known as the oil drain plug) of the oil pan of the automobile engine, it is necessary to do a maintenance and replace a copper washer, otherwise it is easy to cause oil leakage. Even so, the wear of the screw hole of the engine oil pan is also very big. It is also difficult for ordinary auto repair shops to replace one copper washer at a time.
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 452N. 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.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: countersunk head inner bolts, aircraft circuit board pads PD, FPV coupling nuts, copper cap nuts and other products, we can provide you with suitable products Your fastener solution.
