Test Equipment for SHS processes: Safety and standardization

摘要

The test equipment for main operations of self-propagating high-temperature synthesis (SHS) processes (charge mixture, compaction, and synthesis) is considered. A description of its structural components, which are most responsible for the safety and efficiency of operation with powders and their mixtures associated with fire and explosion hazard, is given. For example, a pressure-sealing valve of original design by means of which the protective gas atmosphere and rarefaction or excess pressure can be created in the mill is applied in the crushing cylinder for ball mills. The mold for preliminary compaction uses a teflon insert, which completely excludes the probability for powder intrusion between sliding surfaces of a punch and a body, thereby preventing the possibility for powder ignition from friction sparks. A reaction mold with the filling of the charge mixture by a layer of quartz sand, one destination of which is the removal of flue gases for the prevention of the mold rupture, is designed for SHS with compaction. Safety of the SHS reactor operation is built into all stages of their life cycle from design to operation. In this regard a system of measures and rules described in the corresponding technical documentation, the references to which are given in the article, is developed. Synthesis in the SHS mode is nonhazardous with the fulfillment of necessary strict measures and the adherence of rules.