Classification, composition, and use of expansion bolts


The grades of stainless steel bolts are divided into 45, 50, 60, 70, and 80. The materials are mainly divided into austenite A1, A2, and A4, martensite and ferrite C1, C2, and C4. The representation method is for example A2-70, and before and after “–”, the bolt material and strength grade are respectively represented.


Composition of expansion bolts

Expansion bolts consist of countersunk bolts, expansion tubes, flat washers, spring washers, and hexagonal nuts.



When using, it is necessary to first use an impact drill (hammer) to drill holes of corresponding sizes on the fixed body, then install the bolts and expansion pipes into the holes, and tighten the nuts to make the bolts, expansion pipes, installation parts and fixed body expand into one.

After tightening, the bolt will expand. There is a large head at the end of the bolt, and a circular tube slightly larger than the diameter of the bolt is placed outside the bolt. The tail part has several openings. When the bolt is tightened, the tail of the large head is carried into the open tube, which is punched to expand and fix the bolt on the ground or wall, achieving the purpose of rooting.


Post time: Jul-09-2024