To avoid contamination of vacuum brazing furnace

To avoid contamination of vacuum brazing furnace

Before getting into the vacuum brazing furnace, after waiting for welding of all zero, components should be properly cleaned and cleaning methods available skim acetone cleaning, ultrasonic cleaning or dry grinding (such as glass abrasive). Artifacts pre-cleaning is just to keep the design features of the vacuum brazing furnace systems of the first step. Assume that brazing furnace is clean, and all the operation steps in line with the provisions, cleaning the workpiece in advance is a vacuum brazing guarantee of success. However, if the previous in the impurity artifacts, causes pollution of the stove, and do not pay attention to when using or misuse, as you might expect, the brazing wouldn't have succeeded. Many operators made vacuum brazing furnace, heat treatment, because residual hydrocarbons, workshop is contained in the dirt and high vapor pressure elements of improper cleaning artifacts but often neglected effect of the vacuum furnace pollution sources, these things will be condensed in the cold area of the stove, in the high temperature again into the surrounding environment, and thus affect the brazing quality.
Casting of vacuum brazing furnace pollution is serious, in repeated process, casting is deflated, will soon be on the same furnace brazing happened impact on the quality of components. Do this too often leads to expensive overhaul and internal heating zone components clean or redo. The degassing of any materials should be completed in a vacuum, and should not be done in vacuum brazing furnace. Zinc, cadmium and lead the brazing filler metal should avoid to use, or only in argon or nitrogen partial pressure higher than 500 um, temperature below its vapor pressure under the condition of use, should try to avoid using flux.