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Zhengwei kettle cover lifts the reactor, the lifting motor drags the rope through the suspender to pull the kettle cover up and down, which is convenient for cleaning the materials in the kettle. The structure is simple and the operation is convenient. It is an ideal device for research institutes and research institutions.

The tetrafluoroethylene material can be used for a long time at -180～260oC. This material is resistant to acid, alkali and various organic solvents, and it is almost insoluble in all solvents. At the same time, polytetrafluoroethylene has the characteristics of high temperature resistance, its friction coefficient is extremely low, and it does not stick to the reaction medium. Therefore, it is widely used in reaction materials that cannot be tolerated by metal materials.