In hardware standard parts, some fasteners are called bolts, some fasteners are called screws, and some fasteners are called studs. So what are the differences? Do they refer to the same product? Is it OK to call a bolt a screw or a stud?

Hexagon head bolt

Hexagon head bolt is the outer hexagon bolt that we often say, it can be said that every enterprise will use it in the production, the standard is GB/T5782 or GB/T5783, 5782 standard is half tooth, 5783 standard is the whole tooth.

Its production range from M5 mm to M64 mm can be provided, and there are spot, material according to their own actual requirements, the level can first 4.8, 8.8, 12.9, etc., can also choose stainless steel 304 or 316 materials.

Of course, there are other hexagonal head bolts such as copper, but it is too uncommon, it is only the difference of materials, production standards are the same, hexagonal head bolts can be surface plating treatment.

In the standard of hexagonal head bolt, there is a fine tooth bolt, the head shape is the same, the difference is only in its thread is fine.

Hexagon slotted bolts

It is in the conventional hexagonal head bolt, opened a word slot, the word slot can be used to install it with a word screwdriver, mainly some installation environment is more difficult, when the bolt tightened, hexagonal head tools can not be put down, can only use a word screwdriver to make some minor adjustments.

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Cross recessed hexagon head bolts

This and the above one groove hexagon head bolt is the same, but replace the one groove with a cross groove, the design of the cross groove will be more convenient to use, convenient to install with power tools, and one groove with power tools some easy to slip.

The cross recessed hexagonal head bolts are sometimes combined with some flat gaskets and spring gaskets to be used as hexagonal head composite bolts.

Hexagon head bolt with hole

This is to make a small hole in the head of the standard bolt. The role of this hole is to install a cotter pin on it in the later stage. Some also make a small hole in the tail, which is also used to install cotter pin, mainly to prevent looseness.

Hexagon head reamed hole bolts

Hinge hole bolts are hexagonal head, but it is completely different from ordinary hexagonal head bolts. The difference lies in the three words of hinge hole.

Its smooth rod part is thicker than the thread, and the standard is the same thick, the smooth rod part also needs to be used after grinding without core, it can be used as a very precise shaft to adjust.

For example, if a hinged hole bolt has a thread of M12, then its straight rod is 16mm. Is it very different from a conventional hexagon bolt?

On the standard GB/T27 hinge bolt, there is also a hinge bolt with hole, that is, on the original basis, a small hole is made in the tail of the thread, and its principle is also for the later installation of a split pin to prevent the bolt from loosening.

Hexagon flange bolt

This should be more common, it is under the standard hexagon head bolt, and add a ring of flange surface design, to increase the bolt cap contact area, strengthen the friction coefficient, so as to achieve better locking performance.

The square head bolt is known by its name. It is not a hexagonal head, but a quadrilateral. It is similar to the T bolt, but the T bolt has a beveled plane, while the square bolt is a square head.

The square head and round neck bolt, also known as carriage bolt, has a round head.

In order to facilitate installation and locking, a four-corner cylinder is added under the round cap to be stuck in the groove to prevent the bolt from coaxial rotation during installation.

The anchor bolt is a kind of fastener buried in the ground. Its head has 7 type and 9 type.

It is mainly used for positioning and installation of equipment, which belongs to a kind of large bolt products.