When we talk about of welding, guess that first impression is the dazzling white light, pungent smelling while getting closer, also remarkable protective cloths of welder
When I was a child, I felt curious when I passed by the welding site every time. I couldn’t help but really want to go to see what was going on, but my parents would call me back. They also told us to turn our heads quickly and not look, in order avoid flashing or burning our eyes, even though my curiosity won’t be blocked, a small welding rod has such magic power that make connection in between steel firmly, once a time I picked up half of the used welding rod and burnt it in the fire to see if it can welding with steel.
The modern society has growing needs for steel. In daily life, many things are made of metal, many metal products can not be casted at one time. Therefore, it needs to be welded, welding electrodes play very important roles in the welding process.
The electrode is a metal bar which is covered of the welding coating powder when it is melted at high temperature by arc welding, and the corresponding electrode is usually selected according to the material of the welding work piece, the electrode can be used for welding of the same quality steel or between different kinds of steel.
Structure of electrode
The electrode consists of an inner metal core and an outer coating. The shape of the core is a steel wire with a certain diameter and length. The main function of the core is to conduct an electric current to heat and melt it, the joining parts are filled and melted together.
The material of the welding core can be divided into carbon steel, alloy steel and stainless steel, but in order to meet the welding requirements, there are special requirements for the material and metal elements of the welding core, and the content of some metal elements will be strictly specified, because the metal composition of the core will directly affect the quality of the weld.
There will be mixed powder outside of the electrode which is called coating powder plays an important role in the welding. If the workpiece is welded directly with an electric welding core, substances such as air will enter the molten metal of the electric welding core, and it will also produce chemical reactions in the molten metal, which will directly cause quality problems such as porosity and cracks in the weld, and directly affect the strength of the weld, the coating with special chemical elements will decompose and melt into gas and slag at high temperature, which can effectively prevent the air from entering and improve the welding quality.
The composition of the coating flux is: silicic acid, fluoride, carbonate, oxide, organic matter, iron alloy and other chemical powder and so on, according to a certain proportion of mixed, different types of electrode coating composition is also different.
There are two kinds of flux on the surface of the welding core, and the main components of the coating are basically the same,
There are three common types, namely, Flux, gas generator, and deoxidizer.
a. Flux is a compound that protects molten metal from air as the electrode melts, thus improving the quality of welding.
b.The gas-generating agent is mainly composed of starch, wood powder and other substances, which have some reduction properties.
c. The deoxidizer is composed of ferrotitanium and Ferromanganese, which can improve the wear resistance and corrosion resistance of the metal.
In addition, the electrode surface coating have other types, each type of composition and proportion will be different.
Electrode manufacturing process
The manufacturing of welding rod is to make welding core and coating flux according to the design requirement of welding rod, equivalent coating on the welding rod to meet with specific requirement.
The coil steel are first pulled off the spool, removing the surface rust by a machine, then straightening, cutting into the standard length, 300mm 350mm 400mm, or any other specific length.
Then we need to prepare coating powder, meshing various raw materials to remove impurities, and then pour into the blending machine according to the formula proportion, but also add the sodium silicate (water glass) which is kind of binder, complete mixing all kinds of coating powder by the blending machine
After mixing process, the powder will be put into a mold and pressed by a machine into a cylinder with a circular hole in the middle. The welding core neatly into the machine feeding mouth, both welding care and coating powder will run ahead at the same time, then the powder material will be coated on the passing welding core by the extrusion of the machine
For clamping and welding convenience, the head and tail of the electrode need to be polished to reveal the core.
In order to distinguish the specifications and models of the electrode, it is necessary to make marks on the electrode. As the electrode running on the transiting belt, AWS standard marks will be printed on each welding electrode by the rubber roller, such as AWS E6013, AWS E7018, AWS E6011
After coating, grinding of head & tail and printing marks, the electrode will be delivered into oven and start the next journey of drying
After drying/heating process and random inspection, electrodes can be packed into different retail packages, such 2.5kg carton box, 5kg carton box, 1lb/2lb/5lb plastic tube, clamshell or blister for store retails which will have OEM branding or family look design of different type electrodes
Prata has been in the field for 12 years to build your brand and grow your profits. Let us help you achieve business success.