Service HotlinePin 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
The performance grade 8.8 of stainless steel bolts refers to the material's tensile strength limit of 800MPa and yield limit of 640MPa. The performance grades of stainless steel bolts, studs and studs are divided into 10 grades: from 3.6 to 12.9. The number before the decimal point represents 1/100 of the tensile strength limit of the material, and the number after the decimal point represents 10 times the ratio of the material's yield limit to the tensile strength limit. There are 7 grades of performance grades for nuts, from 4 to 12. The numbers roughly represent 1/100 of the minimum stress that the stainless steel nut is guaranteed to withstand. For unified inch threads, there are three thread grades for external threads: grades 1A, 2A and 3A, and three grades for internal threads: grades 1B, 2B and 3B, all of which are clearance fits. The higher the rating number, the tighter the fit. Classes 1, 1A and 1B, very loose tolerance classes, which are suitable for tolerance fits of internal and external threads. Grades 2, 2A and 2B are the most common thread tolerance grades specified for inch series mechanical stainless steel fasteners. Grades 3, 3A and 3B, screwed together to form the tightest fit, suitable for tight tolerance stainless steel standard parts, for safety critical designs. Metric threads, there are three thread grades for external threads: 4h, 6h and 6g, and three thread grades for internal threads: 5H, 6H, 7H. Thread fit is best combined into H/g, H/h or G/h. For bolts, stainless steel nuts and other refined fastener threads, the standard recommends 6H/6g fit. Carbon steel: The strength grade is marked by ? It consists of two separated numbers. The meaning of the number part before the ? in the marking code represents the nominal tensile strength, for example, 4 in grade 4.8 represents 1/100 of the nominal tensile strength of 400N/MM2. The meaning of the ? and the number part after the point in the marking code represents the yield-strength ratio, that is, the ratio of the nominal yield point or the nominal yield strength to the nominal tensile strength. For example, the yield point of grade 4.8 products is 320N/mm2. The strength grade mark of stainless steel products consists of two parts separated by —. The symbol before — in the sign code indicates the material. Such as: A2, A4 and other signs — indicate strength, such as: A2-70 Carbon steel: The mechanical properties of bolts can be divided into: 3.6, 4.6, 4.8, 5.6, 5.8, 6.8, 8.8, 9.8, 10.9, 12.9 in total 10 performance levels
The flat key is simple in manufacture, reliable in operation, convenient in assembly and disassembly, and widely used. The flat key transmits torque by contacting the two sides of the keyway with the two sides, that is, the side is the working surface, so the main technical requirements for assembly are: to ensure the matching requirements between the flat key and the keyway of the parts on the shaft, and to transmit the movement smoothly and torque. The matching nature of the key and the keyway generally depends on the working requirements of the mechanism. The key can be fixed on the shaft or the hub, and can slide relative to another matching part (guide flat key); it can also be fixed on the shaft and the hub at the same time (ordinary flat key), and based on the size of the key, by changing the shaft The size of keyway and hub keyway can meet different matching requirements.
The retaining ring is divided into two types: shaft use and hole use. Its structural characteristics: The shaft retaining ring is a kind of retaining ring installed on the shaft groove, which is used for positioning and fixing of shaft end parts, and can withstand severe vibration and shock loads, but It is necessary to take anti-loosening measures and installation positioning; the hole is installed in the circular hole with an elastic retaining ring, which is used for the axial movement of the fixed parts. The outer diameter of this retaining ring is slightly larger than the diameter of the assembly circular hole.
The existing welding stud only has one welding spot on the top surface of the screw head, and the welding stud is relatively long and thick. When welding, the current will be relatively large, so that all the welding spots can be melted to complete the welding process. Because there is only one welding spot, and the welding stud is relatively long and thick, the increase of the current during welding will deform the melting point of the metal plate, which will lead to the penetration of the metal plate, which will lead to the concave and convex welding scars on the back of the welded plate, which will affect the appearance. Only one welding spot is located to be welded with the metal plate. During welding, the uneven parallelism of one spot leads to insufficient stability and a certain slope. It is easy for workers to have insufficient stability and parallelism when operating, resulting in wasted time and high scrap rate. increase.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: open-ended round head rivets, slip-knot bolts, GB854 single-ear stop gaskets, nylon gaskets and other products, we can provide you with suitable products for you. Fastener Solutions.
