Most welding flux formulations consist of an oxide-based flux and additives bonded together by sodium silicate. Sodium silicate binders have two important disadvantages. They are very hygroscopic and they require moisture to keep them sound and free from cracks.

Hydrogen can be introduced into the weld arc atmosphere from a number of sources including oxides, wire contaminants and oil. The primary source is moisture in the flux and flux binder.

During welding, the heat evaporates and dissociates the water, evolving hydrogen gas which dissolves into the metal. Under stress, the dissolved hydrogen may produce cracks with the potential for catastrophic failure. In an effort to decrease the possibility of failure, sodium silicate welding fluxes are dried at 200-300° C. to decrease the water content less than 0.2%. The dried fluxes can then be used for only a limited time before the flux again absorbs moisture from the air and has to be redried.

Keenovens company provides drying ovens of different size. There are top-loading and front-loading choices for you. If our submerged arc welding flux get damp due to improper storage, please dry them at 300-350℃ for 2 hours.

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