GERAET ZUR ENTNAHME VON GASPROBEN

摘要

A sample gas extracting apparatus constituted by a plurality of parallel connected constant flow-rate gas lines each having a critical flow Venturi connected in the downstream portion, relative to the direction of gas flow therethrough, thereof and a changeover valve in the upstream portion, relative to the direction of gas flow therethrough, thereof which can be changed over for passing sample gas to the corresponding critical flow Venturi or for passing air to the corresponding critical flow Venturi. A sample gas line is connected to the upstream end of the parallel connected constant flow-rate gas lines and has a sample gas extracting device connected therein just upstream of the constant flow-rate gas lines. A suction device is connected to the downstream end of the parallel connected constant flow-rate gas lines and having a suction capacity greater than the total of the critical gas flow rates of the critical flow Venturi's and less than that which will cause a surging phenomenon in the apparatus.