Service HotlineAccording to the development and evolution process of self-tapping screws, we believe that the main types of self-tapping screws are as follows: 1. Common self-tapping screw threads are self-tapping threads, also known as wide thread. The surface is mostly electroplated. 2. Self-cutting and self-tapping screws are called scraping ends of self-tapping screws in my country's standard. The threads are self-tapping threads or machine threads, and the cross grooves are also H type. There are several types of self-cutting self-tapping screws: cross recessed pan head self-cutting self-tapping screws, cross recessed countersunk head self-cutting self-tapping screws. Cross recessed countersunk head self-cutting self-tapping screws, hexagon head self-cutting self-tapping screws. 3. Self-extrusion and self-tapping screws (self-tapping locking screws) The threads of self-extrusion and self-tapping screws are generally machine threads, and self-tapping threads are rarely used. In the wrenching method, in order to ensure the use of high-speed automatic assembly wrenches, slotting is generally not recommended. The cross section of the screw of the self-extrusion self-tapping screw is triangular. So it is also called triangular thread screw. 4. Self-drilling and self-tapping screws (self-drilling screws) The threads of self-drilling and self-tapping screws are self-tapping threads according to Chinese, German and international standards. In the American ASME and SAE standards, the BSD self-drilling self-tapping screws are self-tapping threads, and the CSD self-drilling self-tapping screws are machine threads. Self-drilling self-tapping screws are not recommended for slotted and normal hex head. 5. Metal driving screws (metal tapping screws) The metal driving screws have multiple threads and special threads with a certain helix angle. Only the American standard has metal drive screws, and there are no Chinese and German standards. 6. Wallboard self-tapping screws (dry wall screws) Wallboard white tapping screws are special threads with horn head, cross groove (H type) and 60° profile angle, and the surface is mostly phosphate treatment (phosphating). 7. The cross groove of the fiberboard nail is Z-shaped, and the surface treatment is mostly electroplating. There are several types of fiberboard nails: countersunk head, double countersunk head fiberboard nails, pan head, pan head flange (with pad) fiberboard nails, semi-countersunk head, semi-countersunk head flange (with cushion) fiberboard nails. 8. Combination self-tapping screws Ordinary self-tapping screws, self-cutting self-tapping screws, self-drilling self-tapping screws, etc., and flat washers, elastic washers (including spring washers, elastic locking washers, etc.). 9. Others Self-tapping screw types High and low thread double lead self-tapping screws, coarse and fine thread (different pitch) thread self-tapping screws, threads coated with sealing material (fall resistance) self-tapping screws, various composite groove self-tapping screws, Other special self-tapping screws, etc. In short, there are many types of self-tapping screws. With the development of production, the advancement of technology, new materials, new structures, and new thread forms, new self-tapping screw products will continue to appear.
Please refer to FIG. 1 , which is a cross-sectional view of a conventional screw and screw washer for locking two metal parts. The screw 100 is combined with the screw washer 110 to lock the metal parts 120 and 130 . The screw washer 110 includes a washer portion 112 and a body washer portion 114 . The washer portion 112 is used for electrically isolating the screw head 102 from the metal piece 120 , and the screw body washer portion 114 is used for electrically isolating the screw body 104 and the metal piece 120 . Therefore, through the design of the screw washer 110 , the screw 100 can be isolated from conducting the metal parts 120 and 130 .
The national standard for the size of the screws in the round head three-combination screw is GB818. The main technical requirements of various types are: iron and stainless steel for material requirements, low, medium and high carbon steel for iron, and stainless steel combination screws The materials are stainless steel 201, stainless steel 304 and stainless steel 316. The thread tolerance is 6G, and the mechanical properties of the iron combination screws are 4.8 and 8.8. The 4.8-level combination screws are ordinary steel, and the maximum allowable hardness is 255HV. The 8.8-level combination screws are generally made of wire rod 10B21. , and then undergo hardening treatment, and then dehydrogenation after hardening treatment. Hydrogen removal is to prevent hydrogen embrittlement of the spring washer in the combination screw. Prevent the spring pad from breaking. The tolerance class of the combination screws is A. The cross groove is H-shaped. The surface treatment of the combination screw has environmental protection and non-environmental protection. Such as, environmental protection blue zinc, environmental protection color zinc, black zinc, color zinc, white nickel and so on. The technical requirement of the combination screw for the spring washer is that the washer should be able to rotate automatically without falling off.
For achieving the above purpose, Guangdong Yueluo Hardware Industry Co., Ltd. provides the following technical solutions: a pin, comprising a pin cap and a described pin rod, the pin cap and one end of the pin rod are fixedly connected, and the pin rod There is a convex body, the convex body is fixedly connected with the pin rod, the convex body is located on the pin rod rod body, and the other end of the pin rod is provided with a top connecting body, and the top connecting body is fixedly connected with the pin rod , the top contact body includes several top contact units and discs, each top contact unit is coaxially arranged with the pin rod, the top contact units are sequentially fixedly connected along the axis direction of the pin, the top contact unit is The major diameter of the outer contour of the connecting body is larger than the diameter of the pin rod.
1. No matter what industry it is, the business is more difficult, and it is still more difficult for the fastener business. After a long period of contact, I realized that the business of making fasteners also requires a lot of attention to be able to do it well. In the business of making fasteners, not just any person can do it, and they all have certain requirements. 2. When it comes to the business of fasteners, no matter what kind of salesperson, the first thing you must have is enough patience, so that we can do this job with confidence, and some customers are not difficult to follow us. Communication, as long as we have enough patience, then we have a greater chance of being able to cooperate with customers on fasteners, and in the face of some relatively large fastener customers, sometimes it is not that we can get it all at once , Sometimes if you want to cooperate, you need to go through multiple contacts to promote a cooperation, so as a salesperson, enough patience is essential. 3. Then, as a fastener salesman, what you need to have is perseverance. Sometimes the salesperson is difficult at work. At this time, you need to adjust it in time, so it will not lead to the phenomenon of giving up easily, after all As a salesman, only through our own efforts can we have the opportunity to receive orders for fasteners from customers. What we need is to be able to face difficulties and move forward bravely. 4. The most important thing for fastener salesmen is to pay attention to details. If we can do a good job in the details, then sometimes we are not far from success. The above are several requirements that need to be met in the fastener business.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: headless hexagon socket screws, coiled screws, 201 screw caps, British and American fine thread nuts and other products, we can provide you with suitable tightening. Firmware Solutions.
