Venturi Mixer, by using of the LPG pressure, ejecting through the supersonic nozzle, and forming into negative pressure in the aspir-ating chamber, absorbing outside air, and exporting after sufficient mixing with LPG in the venturi tube. Starting and stopping of the equipment completes automatically depend on the change of pipe arrangement pressure. Because air is absorbed by negative pressure, which formed by the ejecting of LPG, ejecting pressure of LPG cannot be too low, commonly, it should be above 3kgf/cm2. This equipment has mature technology, stable operation condition and low operation cost. Mixed proportion also can adjust in a cer-tain range, just its export mixed pressure is lower, commonly, below 0.5kgf/cm2. To realize high-pressure transportation, it nee-ds to use air with pressure outside the aspirating chamber, to form into boosting venturi mixer, this equipment can improve its tran-sportation pressure by leaps and bounds, and satisfy long distance transportation needs of the users.

         Venturi, mixed gas ability is definite. In the using process, mixed output and consumption maybe exist matching problem. The measures below can solve this problem:(1) Setting surge tank;    (2)Selecting multibarrelled mixer, and based on the working quan-tity of the starting and stopping of venturi tube automatically of the pipe arrangement pressure, makes mixed output and consumpti-on get to basic matching.

       In mixed gas system, always import the signal of oxygen content analyzer or Calorimeter into control system, for we can know the mixed gas proportion at any moment. When the mixed gas proportion over the allowable range, the mixer can stop working automatically, ensure safety working of the system.

      Sound deadening, filtrating and nonreturn settings included in the air suction inlet, inside the wall of the mixer, also installed noise deadener to reduce noise when operating.