Thermite pressure welding

Welding is a unique way to join metals at the interatomic level, allowing parts to fuse together. There are different ways to do this, and one of them is pressure thermite weldingThermite welding involves heating the metal being welded with thermite, which consists of a powdered mixture of magnesium or aluminum and iron scale. The ratio of aluminum to iron oxide is 37%, with more being used if necessary. These metals generate significant heat upon ignition, and the iron scale serves as an oxygen source.

A mixture of heated thermite is poured into the gap to be welded and held for a certain amount of time, during which the metals recrystallize. Thermite pressure welding Provides a very strong metal connection capable of withstanding heavy loads. This type of welding is successfully used to join cast iron and steel components, such as railway rails, to repair cracks and pipes, and to weld surfaces during track repairs. It is also used to terminate aluminum conductors and connect them in power lines.

Thermite welding technology

Thermite welding technology proceeds as follows:

• the surface to be welded is carefully cleaned and prepared for precise joining;
• The mold is filled with refractory material and secured with clamps. The mold must be dry and free of moisture;
• the heater heats the metal junction to 900 degrees Celsius;
• after preliminary heating, the crucible containing thermite is connected;
• the thermite is ignited by an ignition mixture;
• Thermite heated to 3500 degrees is poured into a prepared mold, completely filling the gap between the parts, ensuring a reliable connection;
• After a few minutes the mould is broken and the welding bead is cleaned off.

Such thermite welding technology This allows for better metal joining results. Thermite can be enriched with ferrosilicon and ferromanganese, which improves its chemical composition, enhances its mechanical properties, and promotes deoxidation. To increase the yield of the thermite mixture, fine iron is typically added at a concentration of approximately 10-151 TP3T of the thermite mixture's weight. Thermite welding technology Aluminum thermite is used in three ways:

1. By melting;
2. Pressure;
3. Combined.

There are many similarities between these methods. The combined method is used when welding rails.

Magnesium thermite welding occurs by melting magnesium oxide (28,000°C). It is used for welding steel telephone and telegraph wires in overhead communication lines.

Thermite welding training

Thermite welding training Includes an understanding of metal joining techniques and the essence of the technological process. Many people undertake self-study primarily to learn how to properly weld wire, which requires:

• prepare a device for welding PTSP, thermal checkers, PAS thermal cartridges - from 70 to 300 grade, thermite matches, asbestos;
• special welding pliers are prepared for the required size of the wire that will be welded;
• the ends of this wire are inserted into the tubes of the thermite cartridge until the insert stops;
• the thermite cartridge tube is sealed with four turns of asbestos to prevent molten metal from leaking out;
• the wires are clamped and secured;
• everything is ready, the thermite match is used to light the thermal cartridge, which is then closed with a casing;
• after 1 or 2 minutes the clamps contract and the wires come closer together;
• when the wire has cooled, the slag is removed and the heat chuck is released;
• The quality of welding is checked for burnout and bending.

Thermite welding training requires hands-on work, which gives confidence when using this type of welding.