What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
The existing spring pads are generally composed of longitudinal support springs, transverse connection springs, support springs, frames and frame clips. (Commonly known as string spring) is a slender and constant warp spring, used to connect the longitudinal support spring. The support spring is located at the edge of the spring pad to increase the shear resistance of the spring pad and the support strength of the frame. The surrounding frame connects the spring to the spring. up, fixed. The existing treatment method is to first heat-process the longitudinal support spring and the support spring made of 70# steel wire through the winding spring in a chemical solution, arrange them, and fix and connect them with a string spring, a frame and a clamping piece. Because the string spring and the frame have not been chemically heat treated, there is a large internal stress. Therefore, this treatment method has two disadvantages. One is that the processing efficiency of the heat treatment support spring is low. Larger, the spring is easily deformed and the service life is affected. In addition, the chemical solution after heat treatment is easy to cause environmental pollution
In another embodiment of Guangdong Yueluo Hardware Industrial Co., Ltd., the conveying device 3 includes a motor 31 and a circular rotating disk 34, the motor 31 drives the circular rotating disk 34 to rotate, and the circular rotating disk 34 is evenly provided with screws in the circumferential direction. The matching screw accommodating hole 35, the screw enters the screw accommodating hole 35, the motor 31 drives the circular rotating plate 34 to rotate, so that the screw is first slotted by the cutting wheel 42, and then polished by the fixing wheel 48, and the screw is in the screw accommodating hole 35. It is fixed, which is more secure and reliable during the slotting process. Preferably, the circular rotating disk 34 includes a circular rotating disk 32 and a sector-shaped fixed disk 33. The circular rotating disk 32 is evenly provided with screw receiving recesses matching the screws in the circumferential direction, and the recesses and the sector-shaped fixed disk 33 are formed with the screws The matching screw receiving holes face the cutting wheel 42 and the fixing wheel 56 .
total of 13 domestic automotive fastener companies were interviewed and investigated in this survey, and all the companies under investigation have passed the TS16949 system certification. An average car has about 1500 fasteners, and the total bolt assembly time for each car is about 2.5~3.2h. It can be seen that the variety and quality of fasteners have an important impact on the level of the main engine and the quality of the vehicle. This article analyzes the localization of high-strength threaded fasteners and the management of supply quality from the perspective of the production process of high-strength threaded fasteners. Product flow of high-strength threaded fasteners The production process of high-strength threaded fasteners is raw material transformation → cold heading forming → thread processing (thread rolling or thread rolling) → heat treatment → surface treatment → sorting and packaging, generally used above grade 10.9 Thread rolling process after heat treatment. The steel grades commonly used for high-strength bolts of automotive fastener materials are 35 steel, 45 steel, and ML35 steel for grade 8.8 bolts; 35CrMo for grade 10.9 bolts; 40Cr; 35CrMo, 42CrMo, and SCM435 for grade 12.9 bolts. The raw materials for domestic fasteners are basically in the hot-rolled state, while the steel for fasteners produced in Japan and other countries is basically in the state of direct cold heading. Users do not need pretreatment, which can reduce costs from the link. Common failure modes of fastener failure are assembly elongation, fatigue fracture, and delayed fracture. In addition to the material, the quality of cold heading forming and thread processing (thread rolling or thread rolling, tapping) threaded fasteners, forming equipment and thread processing equipment and molds (production process and equipment) are the key factors to ensure their quality. Especially in the state of large-scale and multi-variety supply, automotive fasteners that require high machining accuracy, how to ensure product consistency and defect prevention is one of the problems faced by fastener production. For the cold heading equipment and thread processing equipment of the investigated companies, domestic equipment accounts for about 40%, Taiwan equipment accounts for 50%, and imported (Europe, America, Japan) equipment accounts for about 10%; Partial folding, thread streamline upsetting, tooth wrinkles and cracks, etc. Domestic fastener factories are limited by capital or other reasons, and most of them use domestic equipment and Taiwan equipment to produce fasteners for automobiles. To ensure the dimensional tolerance and geometric tolerance of large-scale production of high-end fastener products, online monitoring should be increased. Means and mold making level. Eliminate unqualified products in production, so as to ensure the assembly quality of OEMs and OEMs. [1] About 80% of the surveyed fastener enterprises have heat treatment equipment, and most of them use Taiwan heat treatment process lines; the process line equipment is a continuous mesh belt furnace with atmosphere protection, and the atmosphere, temperature and process parameters are controlled by a computer. The high-strength fastener industry is a relatively competitive industry. If we want to have a thorough and objective analysis of the technology and market of the high-strength fastener industry, we need to start from the following aspects: domestic high-strength fasteners Industry and Enterprise Competition Pattern High-strength Fastener Industry Industrial Policy High-strength Fastener Product Technical Standards and Regulations my country's High-strength Fastener Product Technology Competition Pattern Dynamics Regarding these six aspects, many domestic research institutions have conducted in-depth research and research, and many institutions have long been engaged in research and research in this industry.
According to an aspect of Guangdong Yueluo Hardware Industry Co., Ltd., a rivet insertion mechanism is provided, including a pressure cylinder, a pressure shaft, an insertion nozzle, a bottom plate, a fixing block and a rivet fixing mechanism, wherein one end of the pressure shaft is connected with the pressure cylinder, and the other end is connected with the pressure cylinder. The insertion nozzle is connected, the fixing block is sleeved on the pressing shaft, and is fixedly connected with the bottom plate, the rivet fixing mechanism is installed on the bottom plate, and the insertion nozzle extends into the rivet fixing mechanism and can extend from the rivet fixing mechanism.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
