The study and research into the problems with liquid-oil-gas-carrying tank cars by using nitrogen replaceable equipment;

Investigation on Nitrogen Gas Replacement in Natural Gas Pipeline;

This paper respectively introduces on the nitrogen replacement methods such as subsection,overall,adding isolator and without isolator replacement.

This paper describes the operating principle, technique requirements, design method about the vacuum-pumping, removal of humidity and charge nitrogen equipment of the QDX refrigerator compressor, which is a product incorporating all the technique in mechanical manufacture, computer and electronic control and the vacuum-pumping.