Thread tapping and die cutting

In engineering, the most common compound is threaded. If it's quality, the whole design is reliable and durable.

Tapping is the process of removing chips from a rod or hole with a special tool or by plastic deformation (knurling).

There are threads single-thread and multi-thread, right-sliced or left. Another parameter is the distance between two ridges. There are several thread profiles: universal - conventional triangular; Trapezoidal - its profile is made in the form of a trapezoid; Resistant - for devices operating under high pressure, and pipe, which is used to connect pipes. There is a standard range of threaded connections.

Tapping can be done manually when the cutting tool is inserted into a hand wheel or drill, or mechanically, when cutting is performed on a lathe or lathe.

Before this, it is necessary to perform an additional operation on the part - to make the desired diameter of the hole or rod. If you need to make an internal cutting, a drill is selected, so that the tap is smoothly entering the hole, but at the same time it grasps the volume of metal necessary for chip removal. Otherwise, the tool may break and the thread will be weakened. Usually, the diameter of the desired workpiece is selected according to the existing tables.

Tapping inside the hole is done with a special cutting tool called a tap. It has a working part that performs the very process of cutting, and a shank, intended for fastening the tool to the chuck of a drilling machine, turning, to a hand drill or a wrench. The working part of the tool is made of high-speed steel or sometimes of hard alloy.

Tapping tapping is a rather laborious and complex work, requiring utmost care. First, you need to set the product, so that the tap is strictly in the center, otherwise marriage can not be avoided. When working with a tap, it is difficult to remove chips, because The access to the hole in which threading is performed is difficult. By themselves, taps can often break down due to their small stiffness.

Nevertheless, thread tapping has advantages:

- simplicity of design and manufacturability;

- cutting occurs due to self-feeding;

- the accuracy of the thread depends on the correct tap.

Tapping of the external thread is carried out by a special cutting tool, called a die.

The thread cutting board is made in the form of a nut made of high-speed or tool steel. The sharp edges of the working profile of the tool allow unhindered removal of the shavings from the rod, and the chips themselves freely exit into the hole. Before threading, the part is turned to the required diameter, a chamfer at the end of the bar is made to facilitate the entry of the part into the die and its more correct centering in the part. The plate is fixed in the plate holder. When threading, it is desirable to apply grease to the part. This makes the process easier.