Service HotlineThe combination screw is actually a kind of screw, but it is special. It is generally a three-component or a two-component, but at least it can be called a combination screw. The main difference from ordinary screws is that they are equipped with one more spring washer or one more flat washer than ordinary screws. This is the main difference between the appearance of combination screws and ordinary screws. In addition to the obvious difference in appearance between combination screws and ordinary screws, the main difference is the difference in mechanical properties and uses. The combination screw is a three-component or two-component with a flat washer. Of course, it is equipped with a flat washer by an ordinary screw. When the spring flat pad is attached, the spring flat pad will not fall off. Fastened to form an assembly. In terms of mechanical performance, the combination screw is composed of three accessories, and in terms of performance, three fasteners must be used together. The mechanical properties of the combined screw are stronger when used. More convenient, the biggest advantage of the combined screw is that the production line can be operated conveniently and quickly, and the work efficiency can be improved. The difference between the use of combination screws and ordinary screws is mainly in the breadth of use. The use of ordinary screws is more extensive than that of combination screws. Basically, ordinary screws are used in industrial products, and combination screws! It is only useful for specific product materials. When the screw needs to be used with a spring washer and a flat washer, the combination screw can be used at this time.
Gaskets are divided into: flat washer - grade C, large washer - grade A and C, extra large washer - grade C, small washer - grade A, flat washer - grade A, flat washer - chamfer type - Grade A, high-strength washers for steel structure, spherical washers, cone washers, square bevel washers for I-beam, square bevel washers for channel steel, standard spring washers, light spring washers, heavy spring washers, internal tooth lock washers , Internal serrated lock washers, external serrated lock washers, external serrated lock washers, single-ear stop washers, double-ear stop washers, outer tongue stop washers and stop washers for round nuts, etc.
The research on rivet nuts started in the 1970s in my country and is still in the design and development stage. In the mid-1980s, equipment for the production of blind rivets was introduced from abroad, but no rivet nut has been produced so far. After the inventor's search, no low-carbon steel rivet nut was found to be publicly used.
As one of the screws, self-tapping screws can directly drill holes on the plate to be fixed by themselves and lock them together with the plate to be fixed. They are easy to use and have a good fixing effect, so they are widely used. However, in the prior art, when the screw is perforated on the plate to be fixed, it is prone to skew, which affects the fixing effect and also reduces the aesthetics. To sum up, how to overcome the above-mentioned defects of the screw fixing method in the prior art is a technical problem to be solved urgently by those skilled in the art.
1. Grade C washers do not have Ra3.2 and deburring requirements. 2. Grade C is suitable for medium assembly series, Grade A is suitable for fine assembly series 3. G B848-85 is mainly used for cylinder head screws, others are used for standard hexagon bolts, screws and nuts. 4. Material mechanical property grade: steel 200HV; austenitic stainless steel A200. 5. Marking example: standard series, nominal size d=8mm, flat washer with performance level of 200HV and no surface treatment: washer GB97.1—85 8 200HV
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: thin screw caps, nickel-plated nuts, bridge claw patterns, full-tooth external hexagon bolts and other products, we can provide you with suitable tightening. piece solution.
