Are Steel Structure Bolts Classified Into Grades?

Why such a title? Are steel structure bolts graded? Like other bolts, can it be divided into grade 4.8, grade 8.8 or other different strengths? When we are engaged in hardware sales, we will encounter users purchasing large hexagonal head bolts. We know that in the national standard, large hexagonal head bolts refer to steel structure bolts, and there is only one grade of steel structure bolts in the national standard manual. Grade 10.9 standard, but users need large hexagonal head bolts of grade 8.8, so this creates a paradox. Are there other steel structure bolts of different grades?

The editor will tell you directly that in the national standard, the corresponding strength of steel structure bolts is level 10.9. There are no other strength standards. If users need other strength standards, it can only be the special requirements of users in actual applications. They are not unified with the national standard documents, but they do not affect the production and use of bolts. After all, the standards are also Formulated based on actual applications. We raise this question just to let users know more about the product performance and related knowledge of steel structure bolts to avoid mistakes in the purchasing process. As long as there are no special requirements, the steel structure bolts supplied on the market should be standard 10.9 grade materials. Only by clarifying the standards can you not be fooled by unscrupulous vendors when purchasing.

If we really want to classify the steel structure, we can only do it based on its appearance standards. Among the categories of steel structure bolts, there is also a type called torsion shear steel structure bolts, whose heads are not opposite sides of the large hexagon. Design, and a design similar to a mushroom head, can be seen at a glance from the appearance, and the installation method is also slightly different, but this torsion shear type steel structure bolt is used less. This article will still use the common large hexagonal The head steel structure bolts are mainly used.

Compared with ordinary bolts, the specifications of steel structure bolts are also a bit different. Ordinary bolts can start from M3 at least, and some are even smaller. The smallest specification of steel structure bolts is M16, and the shortest length is 50 mm. So the steel structure The bolts are medium and large bolts. Mainly because steel structure bolts are mostly used in house construction and bridge installation, which have high requirements for their load-bearing performance. If the size is too small, theoretically they cannot match the use environment.

Ordinary bolts are sold separately, that is to say, if you need a bolt, there is only one bolt, and if you need a nut, you need an additional nut. However, the washers and nuts of steel structure bolts are in complete sets, and their washers are also high-strength. , hardened by heat treatment, and its nut is also a large hexagonal opposite edge, thickened and widened, and the strength level reaches level 10.