What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
[In a preferred example of Guangdong Yueluo Hardware Industry Co., Ltd., the cone includes a large diameter end and a small diameter end, the diameter of the large diameter end is the same as the diameter of the inner hole in the middle of the nail body, and the diameter of the small diameter end is Two-thirds of the diameter of the large diameter end.
Pin riveting is an important procedure in the production process. At first, people used manual work, which has low production efficiency, high production cost, and high defect rate of products produced. Later, a pin riveting machine appeared. The pin riveting machine is a For riveting and pinning of hardware products, the pin riveting machine can complete the operation of pin loading and riveting pins, and the pin riveting machine reduces the process of pin loading and riveting pins in the hardware production process. However, its structural design is unreasonable and the operation is very inconvenient
As a special kind of rivet parts, the rivets for shrinking brake pads are used in the accessories of the automobile industry. The original brake pad rivets do not have a chamfered structure, so the materials cannot be normally fed during assembly, or there are burrs, which lead to unqualified batches. When improving this structure, many manufacturers in the same industry often solve the problem by machining chamfering, but for brake pad rivets with thin thickness, it is impossible to achieve the problem of beating and bad material after chamfering processing.
According to the force of the connection, it is divided into ordinary and hinged holes. According to the shape of the head: there are hexagonal head, round head, square head, countersunk head and so on. Among them, the hexagonal head is the most commonly used. Generally, countersunk heads are used where connections are required. [1] The English name of the riding bolt is U-bolt. It is a non-standard part. The shape is U-shaped, so it is also called a U-bolt. There are threads on both ends that can be combined with nuts. It is mainly used to fix tubular objects such as water pipes or sheets such as The leaf spring of a car is called a horse-riding bolt because it fixes the object in the same way that a person rides on a horse. According to the length of the thread, it is divided into two categories: full thread and non-full thread. [2] According to the thread type, it is divided into two types: coarse thread and fine thread. The coarse thread is not displayed in the bolt mark. The bolts are divided into eight grades: 3.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, and 12.9 according to their performance grades. Among them, the bolts above grade 8.8 (including grade 8.8) are made of low-carbon alloy steel or medium-carbon steel and are heat-treated (quenched). + Tempering), commonly known as high-strength bolts, and below grade 8.8 (excluding 8.8) are commonly known as ordinary bolts. [2] Ordinary bolts can be divided into three grades: A, B, and C according to the production accuracy. Grades A and B are refined bolts, and grade C is rough bolts. For connecting bolts for steel structures, unless otherwise specified, they are generally ordinary rough grade C bolts. There are differences in the processing methods of different grades. Usually the corresponding processing methods are as follows: ① The bolts of grade A and B bolts are processed by lathes, with smooth surfaces and accurate dimensions. High, rarely used; ②C-grade bolts are made of unmachined round steel, the size is not accurate enough, and its material property grade is 4.6 or 4.8. The deformation is large during shear connection, but the installation is convenient and the production cost is low. It is mostly used for tensile connection or temporary fixation during installation. [2]
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
