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Precautions for installation and use of four common level gauges

Apr 02, 2019

Precautions for installation and use of four common level gauges

Xi'an Huaheng Instrument Manufacturing introduces the four common liquid level gauge installation and uses precautions.


Precautions for installation and use of the glass tube level gauge:


This level gauge should be guarded against mechanical impact during transport installation to avoid glass breakage, which must be taken care of.


The liquid level gauges have their own specifications and models. Be sure to choose a suitable model. For example, some media should use a colorless light-transmitting liquid level gauge, and some may use a liquid level gauge with a steam jacket. For insulation purposes. Humidity sensor probe, stainless steel electric heating tube PT100 sensor , cast aluminum heater, heating coil fluid solenoid valve.


After the liquid level gauge is installed, when the liquid temperature of the container is high, the valve cannot be opened immediately. It should be preheated for a period of time. After the glass tube, liquid level gauge has a certain temperature, the valve is opened to prevent the glass from expanding and shrinking.


During the use of the liquid level gauge, the inner and outer walls of the glass tube should be cleaned regularly to avoid blurring of the line of sight. When cleaning, the upper and lower valves must be closed to prevent the liquid from flowing out of the container, and then the removed glass tube is rinsed with water or soaked with alcohol. Also, be careful when installing, there are ways to do it.


If the glass tube needs to be replaced, it should be disassembled and installed. When it is installed, try to see if there will be leakage. Only if there is no leakage, it can be put into use.


Always use maintenance and repair during use to avoid leakage caused by rust and corrosion, and make records of use and maintenance.



flange connection water level sensor_meitu_5

Precautions for installation and use of glass plate level gauge:


During installation, in order to ensure the function of automatic sealing, the liquid in the container must have a certain pressure, at least greater than 0.2 MPa. When opening the upper and lower valves, the valve stem should not be less than four turns, because steel When the ball is closed, it will not hit the top of the valve stem to avoid damage.


During transportation and unpacking, be sure not to touch hard parts to avoid broken glass.


Also, pay attention to the specifications and models. It is not possible to install a level gauge that is not suitable for specification. Some media have restrictions on the liquid level device. For example, some media that are corrosive to glass plates or steel plates cannot be used.


Another maintenance cleaning, cleaning, and installation is similar to the glass tube level gauge.


Precautions for installation and use of magnetic float level gauge:


Measurement objects should be considered, such as the physical and chemical properties of the measured medium and the working pressure, temperature, installation conditions, speed of liquid level change, etc.; another is measurement and control requirements, such as measurement range, measurement accuracy, display mode, site Instructions, remote indications, and interfaces to computers, security, reliability, ease of construction, etc., are all considered. Only by fully considering these, you can choose the right one.


When installing, ensure that the level gauge is vertical, and ensure that the float can move freely. It cannot be installed when it is installed. Other matters are similar to the glass tube glass level gauge. Therefore, we only know the installation and use of various level gauges to be able to actually install it.


Precautions for installation and use of magnetic flap level gauge:


Before use, use the calibration magnet to set the ball below the zero levels of the liquid level gauge to red, and the other balls to be set to white.


When the user adds the heating pipe by himself, the non-magnetic material, such as a copper tube, is selected, and the temperature of the heat tracing pipe is determined according to the specific medium. The installation position of the magnetic flap level gauge should also be avoided to avoid or away from the inlet and outlet of the medium, otherwise, the accuracy of the measurement data will be affected by the rapid change of the medium in the local area. At the same time, it should be noted that the medium does not contain solid impurities, or magnetic substances, which will hinder the work of the float.


Around the magnetic flap level gauge, it is also not allowed to have a magnetically conductive material close to it, and do not use a wire to fix the liquid level gauge. This will also affect the normal operation of the liquid level gauge.


When installing, the first thing to notice is to open the bottom of the level gauge and load the float. You need to pay attention to the magnetic end, and you can't reverse it.


After the installation is completed, the pilot valve on the level gauge should be opened first, then the lower valve should be slowly opened to allow the medium to slowly and smoothly enter the detection tube, and observe whether the red and white balls on the level gauge are flipped normally. If it is normal, close the lower guide valve, then open the drain valve, and let the liquid position in the main conduit gradually decrease. Repeat the operation three times. After confirming that the level gauge is working properly, you can put it into normal. Run the job.


Precautions for installation and use of capacitive level gauge:


When installed in the open air, the probe line should not be exposed outside the container to avoid measurement errors on a rainy day.


The stainless steel process connection part of the outer casing or the junction box must be reliably connected to the outer wall of the container (ground) and its contact resistance must not exceed 2.


In normal operation, the probe line should not have a large swing amplitude in the container, otherwise, signal instability will occur.


When installing the probe line, it should be as far as possible from the inner wall of the container. The small distance cannot be < 100 mm. When subject to conditions, the distance between the probe line and the container must be relatively fixed when the distance is <100mm.


For the single-wire soft probe, the excess part can be cut off after the upper end of the process coupling is pulled out, and then the deposit bolt is tightened, and the twisted pair probes, the excess part can be plated above the measured liquid level, and the excess part is absolutely not allowed. Coil around the bottom of the container or an effective measuring section.


When there is agitation in the container or the liquid may generate a large amount of air bubbles, in order to protect the probe line and avoid false liquid level caused by liquid fluctuations and bubbles, a metal or non-metal tube with an inner diameter > 80 mm may be placed in the container, and the lower end of the tube shall be placed. The opening is filled into the liquid hole, and the exhaust hole is left below the liquid surface. When the metal tube is used, the position of the probe line in the tube should be ensured to be quite stable, and the probe line should be straightened if necessary.