Tungsten electrodes are a safe, highly efficient and truly qualitative device for performing welding operations. Currently, specialists actively use products of various markings. The choice of a particular option depends on the nature of the work and the type of welding machine that will be used as a tool for implementing the tasks assigned.
Let's look at the characteristics that distinguish tungsten electrodes. Immediately it is worth noting that such products are used when it is necessary to perform so-called argon-arc welding, in other words - in the course of work, where the rod is heated in a protective gas argon.
The melting point of the material is about 3400 ° C, and the boiling point is about 5900 ° C. Tungsten is the most refractory metal used to make electrodes. As can be seen, the material is capable of retaining the original structure when exposed to the highest temperatures.
To improve the quality of tungsten electrodes, for example, to improve the stability of arc combustion, all kinds of rare earth oxides are used as additives in their production as additives. Depending on the composition of these elements, products of different brands are distinguished.
Tungsten electrodes - marking
According to the standards, products of this category must have a special marking, which indicates their composition and type. The first in the list is always the designation "W", that is, tungsten. Subsequent values indicate oxide, which is used as a dopant.
How to choose suitable tungsten electrodes? The marking makes it possible to speed up the selection of products that will allow most efficiently to cope with the tasks:
- "W" (green) - electrodes made with the use of pure tungsten. To give preference to this solution is recommended when processing aluminum alloys with alternating current.
- "WTh" (red) - toritized tungsten electrodes. Applicable for welding copper, corrosion-resistant steel, titanium under the influence of direct current.
- "WZr" (white) - zirconized tungsten electrodes. The products of this plan can be used for both DC and AC welding. They are used for processing light metals (magnesium, aluminum).
- "WLa" (black) - lanthanized tungsten for processing heavy metals with alternating and direct current.
- "WCe" (gray) - ceramics electrodes, which are used as an alternative to toritized products.
Sharpening of tungsten electrodes
To get a high quality duplicate of the welded connection, sufficient to give adequate attention to the nature of the sharpening products from tungsten. Arc shape at performance of works depends on the angle at which the sharpened electrode. The higher it is, the lower the penetration and wider the spot.
The life of a tungsten product significantly affects its dullness. The way the end of the electrode is flat depends on its diameter, the thickness of the metal and the magnitude of the welding current.
When processing metal not more than ten mm thick, the tungsten electrode is welded from the right to the left. During the processing of denser materials act in the opposite way.
With a manual method of welding a sheet metal, the electrode is introduced somewhat laterally, not into the column of the arc. Metal of greater thickness is processed by transverse motion.
Semi-automatic and automatic welding involves placing the electrode perpendicular to the area being treated. Often, the direction of motion is chosen so that the additive is in front of the arc.
Tips for choosing
When selecting a refractory tungsten product, it is worth paying attention to the following criteria:
- Electrode parameters, marking, composition, character of alloying additives.
- Diameter (depending on the required thickness of the working seam).
- Density of the material of manufacture.
- Quality of sharpening.
- Specific geometry of the point.
Naturally, when selecting electrodes for specific tasks, it's easiest to navigate according to the marking that is applied to the surface of the products by the manufacturers. The latter will indicate possible applications, composition, operating conditions.
Tungsten electrodes are one of the best solutions for performing welding operations. The products of this category are of high quality and efficiency. However, in choosing to pay attention to the whole mass of important characteristics, which can confound the unprepared masters. To facilitate the task, it is worthwhile to refer to the above recommendations.