A self-tapping screw with a press washer is a screw that on top resembles a small squeezed washer. It is used in many fields of industry and construction. Moreover, some say that this invention has no analogues in advantages. What is the difference between a self-tapping screw and a press washer? Let's figure it out.
Varieties
Today, there are two main types of such tools:
- Sharp devices.
- With a drill.
To find out the features of each of them, let's look at both types separately.
Sharp metal screws with a washer
The main material from which they are made is high-strength carbon steel. Moreover, a small layer of zinc is applied to this tool from above during the production process, protecting it from rust and other negative environmental influences. Thus, this self-tapping screw with a press washer is very hardy, reliable and resistant to corrosion. The head (i.e. the head) of this tool has a hemispherical shape, under which there is a welded press washer. Spitz in such a self-tapping screw is most often cruciform.
Where is the self-tapping hemisphere “press washer” used? The main area of its application is the installation of wooden structures and work with various wood materials. Due to the presence of a press washer, the device perfectly presses the sheet material to the surface to be treated, thereby ensuring a reliable and high-quality connection. As a result, a strong and durable construction. And even from an aesthetic point of view, it looks very attractive. That is why a sharp screw with a press washer is a leader among its "brothers."
Drill Devices
They are produced, as a rule, from higher quality steel and are also coated with a thin layer of zinc. The head of this device has a hemispherical shape, and the press washer is placed on its back side. And if the design of this tool may have some similarities with the first, then with the scope it is quite the opposite. The main feature that distinguishes this self-tapping screw with a press washer from others is the ability to work exclusively with a metal surface. The tip of the device, which resembles the shape of a drill, quickly makes a hole in the steel sheet, and the thread goes further into this material. Thus, metal screws with a press washer provide not only a high-quality connection, but also significantly reduce the time to perform certain tasks. It is not necessary to use a drill in this case: if the width of the hole to be drilled is less than 2 millimeters, the self-tapping screw itself can very well handle this work. Well, if there is already a preliminary hole in the metal sheet, the self-tapping screw will independently cope with the necessary task without the help of any other devices.
Price
Like all other tools of this type, these devices are usually purchased in bulk. The approximate price for 1 kilogram of such screws is from 100 to 150 rubles.