Views:12 Author:Site Editor Publish Time: 2017-04-19 Origin:Site
Efficiency, productivity and weld precision are key focus areas in gas tungsten arc welding (GTAW), also known as tungsten inert gas (TIG) welding.
To achieve optimal GTAW performance in these areas, operators must carefully select the right equipment and consumables. Additionally, it is critical that welders consider several factors that will help maximise productivity and quality.The artical introduces the following factors:
Understanding the material is an ideal way to start the GTAW process.Know the material’s unique characteristics and the conditions the finished weld will encounter.To determine the most suitable filler metal for the application, take into consideration situations when anodising is required after welding or when the finished product must pass structural integrity requirements.The importance increases for welding materials that distort or crack, like aluminium.
The focal point of GTAW is the tungsten electrode – the non-consumable metallic element that carries the welding current to the arc. Various considerations should be looked into when selecting the tungsten.
1.There are a range of tungsten electrode diameters – from 1.0mm – 4.0mm.
2.Make sure you select the right thickness for the material being welded.
3.Various types of tungsten electrodes are available, and each are suited to specific materials, so you will need to choose the most suitable for your application.
4.Tungsten electrodes are made up of either pure tungsten or a mix of other rare-earth elements and oxides. Each are colour coded to help you identify their type.
5.When AC welding, tungsten electrodes that are suited to aluminium and magnesium alloys should be used. For DC welding, tungsten electrodes suited to stainless steels and other exotic materials can be used.
Proper grinding techniques are critical to tungsten life and improper preparation can significantly affect the welding arc.
When DC welding, a sharpened tungsten is preferred for direct current. Grinding the taper distance to about 2 electrode diameters in length to a sharp needle point and using a 30-degree angle is recommended.
Advanced AC tungsten preparation should be prepared like DC – with a blunted end to allow a ball to form that is equal to, or slightly larger than the diameter of the tungsten at the melt back point where the ball stops forming.