In standard hardware parts, some fasteners are called bolts, some fasteners are called screws, some fasteners are called studs.

So what are the differences, and are they referring 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 bolts such as copper.

But it is too uncommon, it is just the difference of materials, production standards are the same, hexagonal head bolts can 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 bolt – it is on the regular hexagon head bolts, opened a slotted, this is the purpose of the slotted can use a screwdriver to install it, mainly some relatively difficult installation environment, when the bolt is tightened, hex head tool lets not bottom go to, can only use a screwdriver to a slightly adjusted.

Cross slotted hex head bolts – this is the same as the one slotted hex head bolts above, but replace the one slotted hex head bolts with the cross slotted head bolts.

The cross slotted head bolts are designed to be more convenient to install with power tools, and the one slotted head bolts are easy to slip with power tools.

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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 bolts with holes – this is a small hole in the head of the standard bolt.

The purpose of this hole is to add a split pin to the head. Some bolts also have a small hole in the tail for the split pin, mainly to prevent loosening.

Hexagon head articulation hole bolt, articulation hole bolt, although is also a hexagon head, but it with regular hexagon head bolts are not the same, articulation hole distinguishes between these three words.

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 bolts – this should be more common, it is under the standard hex head bolts, and an additional ring of flange surface design, to increase the bolt cap contact area, enhance the coefficient of friction, 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.