Independent threading on pipes of a different class requires from the performer certain skills and knowledge of all the subtleties of this procedure. In this article we want to acquaint you with how to cut the threads on the pipe with your own hands (on a water pipe, on a stainless pipe).
Mastering a thread-cutting technique will allow you to independently engage in the repair of plumbing and heating networks, as well as any household appliances that include pipe products.
Manual thread cutting
Pipe-cutting techniques blanks involves the use of the following techniques:
Thus, the preparation of threaded connections in the home is only possible with certain tools and equipment. In this article, we will consider in detail the method of threading using a special thread-cutting kit (the so-called "die").
Manual screw die set
Electromechanical threading kit called "screw die" is used in conjunction with a set of radial dies of different diameters, designed for cutting threads on tubular blanks of any dimension. In addition to the fixture itself, you will need the following tools and materials for threading:
At once we draw your attention to the fact that it is allowed to work with an electric sander only with gloves and goggles.
Making the thread
First turn using a grinding machine is cut off part of the water pipe with an old thread or its portion damaged by corrosion.
To form a high-quality cut, which guarantees the convenience of carrying out all subsequent operations, immediately after marking, the pipe segment is rigidly fixed with a gas key or clamped in a vice. Further, on the prepared section of the pipe, a thin chamfer is cut off, which noticeably facilitates the rotation of the die. To facilitate its sliding along the thread, the cutting area is lubricated with engine oil.
During threading, the die holder rotates clockwise; but after the formation of several threads, the direction of its rotation is reversed. Using this technique allows you to free the working area from spent metal shavings.
Thread cutting on the riser
The length of the threaded connection must not exceed 1 cm That corresponds to the standard indicator for most household pipe networks. At the end of the thread cutting procedure, the treated area is cleaned of metal shavings, and then carefully wiped with a cloth or rag.
Before cutting the thread on the pipe in its internal cavity, you will need to measure the diameter of the tube hole. Based on the data, you can choose a working tool (tap) of the desired size. Pay attention to the length of the pipe section protruding from the wall was a few millimeters longer than the cut thread.
After you have finally decided on the required diameter of the inner hole, you should drill out to a size suitable for threading.
In the process of drilling, you need to carefully monitor the position of the input part of the drill, which should not deviate from the vertical.
At the end of the preparatory operations, a tap of the required diameter is inserted into the tube hole with simultaneous rotation of its base in a clockwise direction. Rotation is carried out with the help of the so-called "wrench" included in the tool kit.
The procedure for the preparation of a female thread involves the use of the following working tool:
Thus, to obtain a high-quality and complete thread, you first have to “walk” through the inner cavity of the pipe with a No. 1 tap, and then repeat the same operation using the No. 2 tap. All these works should be accompanied by the introduction into the working area of small portions of engine oil.
The principle of threading is no different from the usual situations described above. The only difference is that it is extremely inconvenient and problematic to perform these works near the wall. For example, sometimes you want to slightly hollow a section of the wall near the pipe. It is very important to carefully cut. If it is uneven, then there will be difficulties when cutting, and considering that you have already made a recess in the wall, it will be extremely difficult to cut the threads. You can use the plate to complete this task. Pre-pipe and smear the plate, and after starting to cut the branches.
If the pipe near the wall has a large diameter, then the task of threading becomes more complicated. In such circumstances it is necessary to use not a die, but a screw die. For convenience, it is better to use an electrical screw die.
As for threading on a stainless pipe, the task is complicated by the fact that the metal used is rather hard. Therefore, for cutting should choose the appropriate steel grade dies. In this case, the appropriate option would be marking R18, and better R18F2. The letter "F" means that the material contains a regulating additive of vanadium up to 2%. In addition, for cutting threads on a stainless pipe, you can use dies marked P9.
If you pick up a die of an inappropriate mark, you can end up with no die and no thread. In some cases, making the thread is possible only on the shaft with a chisel.
Instructions for threading a die: