PURPOSE: To increase capacitive property even when the pressure inside a gas meter tube or the like is negative by a constitution wherein an agitating mixer having a restricted part is provided on the upstream side of a gas separating column in a carrier gas channel supplying a gas to a gas chromatograph.
CONSTITUTION: When degasified insulating oil 2 is present in a transformer case 1, the pressure in a gas holding chamber 4 and a gas meter tube 6 connected to the former becomes negative. When a hexagonal selector valve 5 is switched under this condition, the gas meter tube 6 is put in a state of connection to carrier-gas input and output pipes 10 and 11. Then, a carrier gas is sent from an air feeding unit 12, and thereby a gas present in the meter tube 6 is introduced into an agitating mixer 21. The introduced gas is expanded after it is restricted by a restricting part 24, and further it is agitated and mixed by the presence of a gas collision board 26. The gas is introduced afterward into a gas separating column 16 via an opening 27, and measured in a state wherein the effect of the negative pressure is reduced.
GANGE TOSHIHIKO
SUGAWARA TOSHIO
TSUKIOKA TOSHIO
TANI ICHITAROU
SHIONO SHIGEO
MORI ETSUNORI
HITACHI LTD