SevenStar D07-7C / ZM, Инструкция по эксплуатации

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6. CAUTION
6.1 Medium Forbidden
The gas of using should be purified without dust 、 liquid and oil stain. When necessary, it should be added filter to
gas circuit to make sure gas purification. If the outlet of MFC connects with liquid sources, which should be
added simple directional valve of MFC outlet to avoid the liquid is refluent to the tube to destroy MFC.
6.2 Corrosive Gas
The materials of bypass are anti-caustic materials like 00Cr17Ni14Mo2(same as 316Lstainless steel), Teflon, and
Viton. When users operate in condition of without vapor, low leakage, regular cleaning and proper operating,
MFC could possible control the normal corrosive gas. Using ammonia, organic solvent gas such as acetone or
other strong caustic gas (like BC13 and BBr3), please informed while your order statements. Valves sealing
materials usually are Viton, for D07-11/11A/12/12A MFC could also used Teflon. While Teflon has been selected,
there maybe leakage happened of valve port, valve sealing leakage rate will lower than 2% of full scale flow rate;
when use the special caustic gas, all sealing materials should be changed relatively.
For the cases that the MFC/MFM used with toxic, pyrophoric, flammable or corrosive gas, you should
ensure that the fixing and fitting are airtight. It becomes necessary to remove the controller from the
system, purge the controller thoroughly with a dry inert gas such as nitrogen, before disconnecting the gas
connections. Failure to purge the controller could cause a fire or explosion resulting in death.
6.3 Seal of Valves
The Valve of MFC is an electric-magnetic valve for adjustment, which is not a solenoid plug valve so that could
not perform that kind of function. Users should better have that plug valve by themselves. Especially when users
operate with caustic gas, general speaking, it should separately add one cut-off valve of MFC inlet and outlet to
protect operating security. After a long period operating, if the leakage rate of MFC valve outlet is not beyond 2%
F.S, which is the standard situation. Otherwise, it should be under maintaining.
6.4 Valves Operating
When valve is operating PURGE, which should not be directly turned to AUTO, operation should be turned the
switch to OFF position and then turn it into AUTO to operating.
6.5 Installation Position
Keeping installation surface horizontal while installation. Please provide the installation position when ordering
the MFC. We will calibrate products according to the requirement of customers. The MFC might show the zero
drift if it is not installed as the same position of calibration. Customer can adjust zero to fix it.