Welding rods are a commonly used welding material, but they can sometimes be difficult to use. Problems such as excessive spatter, unstable arcs and poor weld formation can be caused by poor quality welding rods.
Fortunately, there are simple methods for inspecting welding rods, even if you don't have access to professional testing equipment. Allow me to briefly introduce some of these methods.
Related Reading: How to Choose the Right Welding Rod?
1. Simple method for welding rod quality inspection
1. Inspection of real welds
The quality of a welding rod can be inspected by examining the resulting welding joint. A high-quality welding rod will produce a stable arc during welding, with uniform fusion of the welding core and cladding. There will be minimal spatter and the resulting weld joint will be well formed with easily removable slag.
2. Coating strength inspection
One way to test the quality of coating strength on a welding rod is to lift the electrode to a height of one meter and let it fall freely onto a thick, smooth steel plate. If the coating does not come off, it indicates that the strength of the coating meets the required quality standards.
3. Appearance inspection
The coating surface of the welding electrode must be smooth and uniform, without pores or mechanical damage. The coating must also be free from any eccentricities and the welding core must be free from corrosion.
4. Physical and chemical inspection
To ensure the quality of the welding rod, it is necessary to double-check the chemical composition and mechanical properties of the deposited metal in accordance with the engineering design requirements.
2. Methods for identifying electrode deterioration
(1) To determine whether a welding electrode is dry or wet, place several welding electrodes in the palm of your hand and roll them against each other. If you hear a clear metallic sound, it is a dry welding rod. If you hear a low rustling noise, it's a wet welding rod.
(2) To check whether an electrode is wet, short it in the welding circuit for a few seconds. If granular spots appear on the surface of the coating, it is a wet electrode.
(3) Wet electrodes often have rust marks on the welding core.
(4) For electrodes with thick coatings, bend them slowly up to 120°. If a large amount of coating falls off or there are no cracks on the surface of the coating, it is a wet electrode. Dry electrodes will produce a small, brittle sound when bent slightly, and when bent to 120°, a small crack will appear on the side of the stressed coating.
(5) If the coating falls off in large pieces or if a significant amount of water vapor is generated during welding, this is an indication that the electrode is wet. In these cases, the wet electrode must be discarded.
Although wet electrodes can be reused after drying, it is important to note that low hydrogen welding rods for important projects cannot be used if there is rust on the welding core.
