For mine hydraulic support, oilfield development, engineering construction, lifting transport, metallurgy forging, mining equipment, ships, injection molding machinery, agricultural machinery, machine tools and the industrial departments mechanized, automatic hydraulic system in transportation has certain pressure and temperature of oil base (such as mineral oil, soluble oil, hydraulic oil, fuel, lubricating oil) and water-based liquids (such as emulsion, oil-water emulsion, water) and liquid transmission pipeline.