SU1180703A1 - Metering cock for gas chromatograph - Google Patents

Abstract

CRANE-DISPENSER FOR GAS. YOUR CHROMATOGRAPH, comprising a housing on which there are two dimensional volumes with input and output channels, input and output channels of the sample and carrier gas, and inside it a distribution rod with sealing rings, characterized in that The goal is to increase the accuracy of the multicomponent mixture analysis, the volumetric volumes are connected in series, the sealing ring on the rod at the output channel of the second volumetric volume is made with a thickness exceeding the diameter of the output channel of the volumetric volume, and The distance from this channel to the input channel of the carrier gas is 1.5 times greater than the distance between the input and output channels of the carrier gas, the distance from the input channel of the carrier gas to the input channel of the second, measured volume and to the output sample channel i are equal to the distance between any neighbor (L them o-rings on the c: stem and three times the distance between the input and output channels of the carrier gas of the second dimensional volume, which is equal to the step of moving the rod between fixed positions. 00 about with

Description

The invention relates to the field of gas analytical instrumentation and can be used as a device for introducing a sample into a chromatographic column. When sampling a multicomponent gas mixture alternately into two independent dosing cranes, it is possible to change its composition over time if the sample is taken from the stream, where the content of the multicomponent gas mixture is continuously measured, the resulting analysis results are therefore not reliable. The purpose of the invention is to improve the accuracy of the analysis of a multicomponent gas mixture. FIG. 1 shows the dosing valve in the Sample Set position; in fig. 2 - the same, in the position of entering the first sample; in fig. 3 - the same, in the position of entering the second sample. The metering crane consists of body 1 with shturcera 2-7 for sample and carrier gas, rod 8 with sealing rings 9-13, two dimensional volumes 1 and 15, located on body 1, channels 16-25 dp of gas carrier and sample polusheni clamp 26, which is made so that when switching the metering valve from one position to another, the magnitude of the longitudinal movement of the rod corresponds to the distance between the channels for the carrier gas, which flushes the mixture out of the second volumetric volume into the BTopyi-o column. The thickness of the sealing ring 9 is larger than the diameter of the output channel 22 of the dimensional volume 15. The valve operates as follows. The rod 8 is set to the Sample Set position (Fig. 1). The gas mixture under analysis is fed through fitting 2 and channels 16 and 25 into the first measuring volume 14 and then through channels 24 and 23 into the second measuring volume 15 and through channels 22 and 21 and fitting 7 it releases to the atmosphere. At the same time, the gas carries along two parallel lines. the lines enter through nozzle 3 channels 17 and 18 and nozzle 4 from the first column, and through nozzle 6, channels 20 and 19 and pin 5 to the second column. After filling the measured volumes 14 and 15 with the analyzed gas mixture, the strips 8 switch to the first position samples (Fig. 2). In this case, the carrier gas passes through the nozzle 3 and the channels 17 and 25 into the measuring volume 14 and flushes the analyzed mixture in it through the channels 24 and 18 and the nozzle 4 into the first chromatographic column. The carrier gas entering through the nozzle 6, the channels 20 and 19 and the nozzle 5 into the second column does not change its path. At the same time, the channel 23 is isolated from the carrier gas flow by sealing rings 10 and 11, and the channel 22 is plugged by the sealing ring 9. Thereby, the selected gas mixture in the volume of 15 is locked, since the sealing ring 9 on the rod 8 has a thickness greater than the output diameter channel and can. silence it, and the distance from the input channel of the carrier gas to the output channel of the measured volume is one and a half times the amount of movement of the rod from the first position to the second. In addition, the distance from the input channel 23 to the input channel 20 of the carrier gas is equal to between the sealing rings on the rod and three times the distance between the channels 19 and 20 for the carrier gas. Due to this, when switching the valve from the first cavity to the second sealing ring 10 remains between channels 19 and 23 and does not change the flow of carrier gas from the input channel 20 to the output 19, and locks the input channel 23 with rings 10 and 11. After analyzing the gas mixture on the first chromatographic column, the rod 8 is set to the second sample entry position (Fig. 3). In this case, the flow of carrier gas through nozzle 2, channels 16 and 25, volume 14, channels 24 and 18 and nozzle 4 does not change, and along a parallel line, the carrier gas through nozzle 6 and channels 20 and 22 flushes the second sample, which is in the second volume 15, through channels 23 and 19 and fitting 5 to the second chromatographic column. Due to the fact that the distance from the input channel 20 of the carrier gas to the sample discharge port 21 is three times greater than the amount of movement of the rod from one position to another when the kronozator switches to the third position. Entering the second sample, the sealing ring 9 isolates the output channel 22 secondary 31

a dose swarm from the discharge channel 21, and a sealing ring 10 isolates the inlet and outlet channels 19 and 20. the carrier gas, which ensures that the sample carrier flushes the sample from the measuring volume 15 to the second column.

Thus, using a single metering tap, a simultaneous set of the analyzed mixture is produced in two successively connected measured volumes. Entering a mixture of one

FIG. one

1807034

volumetric volume into the chromatographic column and simultaneous closure of this mixture in the second volumetric volume, and after chromatographic separation of the gas mixture from the first volumetric volume, entering the mixture from the second volumetric volume into the second column allows for a complete analysis of the multicomponent gas mixture from a single sample , the most simplified analysis of the analysis and ensuring its reliability.

/five

U

Phage.1

five

/five

FIG. five.

Claims (1)

* 603852, class G 01 F 11/00, 1977., CRANE DISPENSER FOR GAS * CHROMATOGRAPHY, containing a housing on which there are two measured volumes with input and output channels, input and output channels of the sample and carrier gas, and inside it there is ¹ distribution rod with o-rings, characterized in that, in order to improve the accuracy of analysis of a multicomponent mixture, the measured volumes are connected in series, the sealing ring on the rod at the output channel of the second measured volume is made with a thickness exceeding the diameter of the output channel of the measured volume, and the distance from this channel to the inlet channel of the carrier gas is 1.5 times the distance between the inlet and outlet channels of the carrier gas, the distance from the inlet channel of the carrier gas to the inlet channel of the second measured volume and to the “outlet channel of the sample are the same, S3 equal to the distance between any adjacent o-rings on the rod and three times the distance between the inlet and outlet channels of the carrier gas of the second measured volume, which is equal to the step of the movement of the rod between fixed positions.