FLK Gas Sampling System - MPIP - Free

Siemens
SQ253 Valve Combination
1.3 Field of application
The valve combination is used for the automatic cleaning of FLK Gas Sampling Probes which are mainly used for measuring
gas sampling up to approx. 1800 °C with a high dust content.
Due to the high dust concentration in the process gas, dust deposits in the sampling probe and in the heated filter are
unavoidable. Therefore, automatic, cyclical cleaning has been implemented for the probe and the filter. The mechanical parts
required for this are accommodated in the valve combination. If a compressed air motor is being used for the "emergency
withdrawal" of the probe, the control valves needed for the motor are also in the valve combination.
Note:
See also the general operating manual for the FLK Probe.
1.4 Construction
The valve combination is designed as a compact unit (see Figure 2). All the parts required for flushing, the valve unit for the
control of the compressed air motor (Item 4, optional), and the drive motor for the four-way ball valve (Item 10) are
accommodated so that they are protected from dust, splashing water and from mechanical damage. A compressed air filter
with automatic condensate drain is connected in front of the filter in the compressed air line. Maintenance-free ball tap (Items
2) are provided for shutting off the compressed air during maintenance work. The compressed air filter and the ball tap are
fitted on the outside so that easy operation and cleaning are possible.
The buttons for starting and stopping the flushing are located on the front panel.
With this construction the valve combination should only be opened in case of a fault or for maintenance work.
A condensate vessel is fitted on the side before the four-way ball valve for retaining the condensate arising after the
electrically heated filter.
Note:
If a heated line is being used for passing the measuring gas between the probe and the analysis cabinet, the
condensate vessel (Item 9), four-way ball valve (Item 10) and low-pressure pressure switch are located in the
analysis cabinet so that the heated line can be cleaned when flushing.
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