Hardware - are the most common way of attaching two parts to each other, because with their help you can easily connect them and after a certain time simply disconnect them. At the same time, the load transfer to the fastening element is created through geometric closure. Therefore, for each slot, you need to choose the right tool: a screwdriver, a key or a bit.
Main types of slits
Straight slot SL
|
This type of slot is considered the simplest and cheapest. But considering the fact that it is considered the oldest, this type has a number of significant disadvantages:
Therefore, such a slot is used less and less. |
Cross slot PH
| It looks like two intersecting straight lines. This type of slot, in contrast with a straight one, has better properties - 4 edges greatly simplify the effort when tightening the screw, but a small area of effort can cause damage to both the hardware, and the tool. |
Cross slot PZ
| This slot is a further development of PH, because they are distinguished only by two auxiliary lines, which are much narrower than the main ones. In this way, the manufacturers managed to improve the twisting characteristics. But the problem of a small area of effort did not go away. The Pozidriv slot is often confused with the Phillips slot, which, if used incorrectly, leads to rapid wear of the tool and screw. |
Torx
| Torx is a star-shaped slot with rounded ends. Compared to classic slots, it transmits torqu better without damaging the bit and screw. Also, this method of twisting increases the service life of the tool due to a number of radial forces. This result was achieved due to the absence of edges, the parallel shape of the exciting profile and the application angle of only 15 degrees. |
Internal hexagon
| Such a slot is considered the most widespread. It is six faces that are placed at an angle of 120 degrees relative to each other. For the transmission of force, this is a relatively not very good design due to the high stress concentration. As a result of great efforts - deformation of the screw. |
The proverbial hexagon
| The hexagon is one of the most famous and widespread profiles. In a hexagon, six surfaces are located at an angle of 120 ° to each other. This is a relatively unfavorable design for force transmission due to high stress concentration. The result of applying large forces can be the deformation of the screw. |
Other species
Star-shaped Torx + Pin
| This slot does not differ in its properties from the usual Torx. The difference is only in the design, in the middle of this there is a small pin that needs a special bit for installation. |
Spanner
| Protective slot with two squares. Spanner screws have a very low application in industry and small production. Force transmission is due to high stress concentration. Not suitable for conveying big moments. |
Protected hexagon (Imbus-Pin, Hex-Pin)
| Hexagonal slot with a hidden pin (Pin). These can be anti-vandal screws with a semi-circular, ART 9111 or concealed, ART 9113 head or anti-vandal self-tapping screws similarly with a semi-circular, ART 9110 or concealed, ART 9112 head. |
What type of slits is best and how to choose?
When choosing a slot, you need to pay attention to a number of factors:
- The field, in which metalwork will be used
- Is it planned to dismantle the hardware product
- How big the torque should be
It should also be taken into account that a bit must be carefully selected for each slot. And it will be different for each slot. When using an incorrect tool, the structure or the fastening element itself may be damaged.