Alginate Application in Welding Rod
In welding rod (welding electrode) industry, coating acts as a flux and to control the condition in the immediate vicinity of the weld, such as temperature or oxygen and hydrogen availability. In this case, sodium silicate (water glass) is used to be mixed with dry ingredients of the coating to gives some of the plasticity necessary for extrusion of the coating into the rod and bind the dried coating on the rod.
Good Performance as Lubricant
However, the silicate neither binds nor provides sufficient lubrication to allow effective and smooth extrusion. An additional lubricant is needed, and a binder that will hold the damp mass together before extrusion and maintain the shape of the coating on the rod during drying and baking. Alginates are used to meet these requirements.