Liquid level gauge installation and use and precautions
Precautions for installation and use of glass tube liquid level gauge:
When transporting and installing this liquid level gauge, beware of mechanical impact to avoid glass breakage, which must be taken care of.
Liquid level gauges have their own specifications and models. Be sure to choose a suitable model. For example, some media need to use colorless light-transmitting liquid level gauges, and some may need to use liquid level gauges with steam jackets. , used for heat preservation.Humidity sensor probe, stainless steel electric heating tube PT100 sensor, cast aluminum heater, heating ring fluid solenoid valve.
After the liquid level gauge is installed, when the temperature of the liquid in the container is very high, the valve cannot be opened immediately. It needs to be preheated for a period of time, and the valve should be opened after the liquid level gauge with glass tube reaches a certain temperature. The purpose is to prevent the glass from breaking due to thermal expansion and contraction.
During the use of the liquid level gauge, the inner and outer walls of the glass tube should be cleaned regularly to avoid blurred vision. When cleaning, the upper and lower valves must be closed tightly to prevent the liquid from flowing out of the container, and then the removed glass tube should be rinsed with water or soaked in alcohol.Be careful when installing, and have a method.
If the glass tube is broken and needs to be replaced, it is necessary to pay attention to disassembly and installation. After installation, it is necessary to test whether there will be leakage. Only when there is no leakage can it be put into use.
When in use, it is necessary to check and maintain frequently to avoid leakage caused by rust and corrosion. At the same time, use records and maintenance records must be made.
Precautions for installation and use of glass plate liquid level gauge:
During installation, in order to ensure the automatic sealing effect, the liquid in the container must have a certain pressure, at least greater than 0.2MPa. When the ball seals the door, it will not touch the top of the valve stem, so as not to be damaged.
In the process of transportation and unpacking, be careful not to touch hard objects, so as not to break the glass plate.
Also pay attention to the specifications and models, and do not install liquid level gauges with unsuitable specifications. Some media have restrictions on liquid level gauges. For example, some media that are corrosive to glass plates or steel plates cannot be used.
Other maintenance cleaning, dismantling and washing installation are similar to the glass tube liquid level gauge.
Precautions for installation and use of magnetic float level gauge:
The measurement object should be considered, such as the physical and chemical properties of the measured medium, working pressure, temperature, installation conditions, the speed of liquid level change, etc.; another is the measurement and control requirements, such as measurement range, measurement accuracy, display mode, on-site Instructions, long-distance instructions and computer interface, anti-corrosion, reliability, construction convenience, etc., these are all to be considered, and only when you fully consider these, can you choose the one suitable for use.
When installing, ensure that the liquid level gauge is vertical, and at the same time, ensure that the float can move freely. When installing, it cannot be installed backwards. Other matters are similar to the glass plate glass tube level gauge.Therefore, we can only really install it if we know how to install and use various liquid level gauges.
Precautions for installation and use of magnetic flap liquid level gauge:
Before use, use the calibration magnet to set the ball below the zero level of the liquid level gauge to red, and the balls in other parts to be set to white.
When users add heat tracing pipes by themselves, they should choose non-magnetic materials, such as copper tubes, and the temperature of heat tracing pipes should be determined according to the specific medium.The installation position of the magnetic flap level gauge should also be avoided or far away from the inlet and outlet of the medium, otherwise the accuracy of the measurement data will be affected due to the rapid change of the medium in the local area.At the same time, it should be noted that there should be no solid impurities in the medium, or magnetic substances, which will hinder the work of the floating ball.
Around the magnetic flap liquid level gauge, it is also not allowed to have magnetically conductive substances close to it, and do not use iron wire to fix the liquid level gauge, which will also affect the normal operation of the liquid level gauge.
When installing, the first thing to pay attention to is to open the bottom of the liquid level gauge and install the float ball. It is necessary to pay attention to the magnetic end upwards and not to install it backwards.
After installation, when debugging, you should first open the guide pipe valve on the top of the liquid level gauge, and then slowly open the valve below, so that the medium can slowly and steadily enter the detection pipe, and observe whether the red and white balls on the liquid level gauge are turning over normally. , if it is normal, close the valve of the lead pipe below, then open the drain valve, let the liquid level in the main pipe gradually drop, repeat the operation three times in this way, and wait until the normal operation of the liquid level gauge can be put into the normal drain valve. Run the job.
Precautions for installation and use of capacitive liquid level gauge:
When installed in the open air, the probe line cannot be exposed outside the container, so as to avoid measurement errors when the probe line hits water in rainy days.
The stainless steel process connection parts at the lower part of the shell or junction box must be reliably connected (grounded) to the outer wall of the container, and its contact resistance cannot be greater than 2.
In normal operation, the probe line cannot have a large swing in the container, otherwise the signal will be unstable.
When installing the probe line, it should be as far away from the inner wall of the container as possible, and the minimum distance should not be less than 100mm.When limited by conditions, when the distance is <100mm, the distance between the probe line and the container must be relatively fixed.
For single-wire soft probes, the excess part can be pulled out through the upper end of the process connector and cut off, and then the deposit bolts are tightened. For twisted-pair wire probes, the excess part can be coiled above the liquid level to be measured, and it is absolutely not allowed to remove the excess part. Coiled on the bottom of the container or on the effective measuring section.
When there is stirring in the container or the liquid may generate a large amount of air bubbles, in order to protect the probe line and avoid the false liquid level caused by liquid fluctuations and air bubbles, a metal or non-metal tube with an inner diameter of > 80mm can be placed in the container, and the lower end of the tube should be The opening is used to catch the flow into the liquid hole, and a vent hole is left below the liquid surface. When using a metal tube, make sure that the position of the probe line in the tube is quite stable. If necessary, support and straighten the probe line.
Precautions for installation and use of buoy level gauge
Welding installation of the lower support of the guide steel wire: determine the position at the bottom of the container according to the movement direction of the float of the buoy liquid level gauge, and weld or rivet to fix the lower support of the guide steel wire.If the equipment does not have welding conditions, heavy anchors can be used to fix the lower support of the guide wire.If the liquid level in the container does not fluctuate greatly, the guide wire may not be installed.
Guide wire installation
(1) Use force to straighten the steel wire and fix it on the lower support. Be careful not to bend or knot the steel wire, so as not to affect the up and down movement of the buoy.
(2) The guide steel wire passes through the guide ear hook of the float level gauge buoy, and then penetrates into the hook screw, fixes the end of the steel wire and clamps it with a wire clamp, and tightens the hook nut to make it in a tense state, and then puts the Tighten the upper nut to prevent loosening, and then close the cover.
(3) The two guide wires should be vertical to the ground and parallel to each other, and the distance between them should be 300mm.
Ruler installed.The length of the scale of the buoy level gauge is determined according to the measurement range provided by the user when ordering, and it is required during installation
(1) The connecting part of the scale should be straight, smooth, and should not have any unevenness, so as not to affect the normal operation of the weight pointer or cause measurement errors.
(2) The scale should be perpendicular to the liquid level in the storage tank, and there should be no inclination. The verticality of the scale installation should not be greater than 5°, so as not to cause the hammer pointer to get stuck and make the measurement fail.
(3) When welding the scale tripod (item 11), try to ensure that the installation surface is on the same plane and the installation hole is on the same line as above, that is, the scale surface of the * scale and the guides on both sides of the weight pointer should be even. Straight is called a straight line, which makes the weight pointer move up and down flexibly on the scale.Note: The distance between the two ruler tripods is 1 meter.
Installation of buoy connecting steel wire and heavy hammer pointer: one end of buoy and connecting steel wire is clamped and fixed with a wire clamp, and then the other end of connecting steel wire is put into two pre-installed guide pulley boxes, and connected with the heavy hammer pointer Connect, clamp and fix with wire clamps, and finally adjust the guide pulley brackets so that the connecting steel wires are perpendicular to the horizontal, so that the buoy can move flexibly on the guiding steel wires, with a light slippery feeling, no jamming, twisting, knotting, and curling or damage.Note: Master the required length of steel wire.
Installation of buoy connection steel wire and weight pointer: one end of the buoy liquid level gauge buoy and connection steel wire is clamped and fixed with a wire clamp, and then the other end of the connection steel wire is put into the two pre-installed guide pulley boxes, and The weight pointer is connected with each other, clamped and fixed with the wire clamp, and finally adjust the guide pulley brackets so that the connecting steel wire is perpendicular to the horizontal, so that the buoy can move flexibly on the guiding steel wire, with a light slippery feeling, no jamming, twisting, hitting Knots, curls or damage.
Precautions for installation and use of ultrasonic liquid level gauge
Ultrasonic level gauge selection range: If you measure liquid, you can choose according to the nominal range.If it is to measure solids (please consult the sales staff of the manufacturer in advance), the measuring range needs to be increased. If it is a soft object (such as flour cotton sponge), it cannot be used.If there are bubbles with large coverage in the measurement liquid level, it is also not recommended to increase the range if the bubble thickness exceeds 5cm.There is dust or steam in the air, please consult the manufacturer's technical personnel in advance to increase the range.
The choice of probe material for ultrasonic level gauge mainly depends on whether the environment is corrosive: ordinary probes can be used in general weak acid and weak base environments, and anti-corrosion probes should be used in highly corrosive environments.In the case of strong acid and alkali, we also need to consider whether fog will be formed, and in the case of fog, it is also required to increase the range of use.
The installation position of the probe depends on the emission angle and possible false reflection echoes: the ultrasonic beam is focused by the probe, and the emission of the pulse beam is like the beam of a flashlight. The emission angles of different types and ranges of probes are different.Any objects within the launch angle, such as pipes, container supports and other devices, will cause strong false echoes, especially within the few meters closest to the probe within the launch.
When the transducer emits ultrasonic pulses, it has a certain emission angle.Between the transmitting surface of the transducer and the surface of the measured medium, there must be no obstacles in the area radiated by the emitted ultrasonic beam.Therefore, when choosing the installation location of the transducer, avoid obstacles as much as possible, such as ladders, brackets, pump valve equipment, etc.If it cannot be avoided, the false echo can be filtered out through program adjustment.The transducer should be perpendicular to the surface of the measured medium to ensure that the reflected echo signal can be received.In addition, there must be a sufficient distance between the transmitting surface of the transducer and the maximum liquid level, and the maximum liquid level must not enter the measurement blind area.
When the transducer emits ultrasonic pulses.All have a certain launch angle.Between the transmitting surface of the transducer and the surface of the measured medium, there must be no obstacles in the area radiated by the emitted ultrasonic beam.Therefore, when choosing the installation location of the transducer, avoid obstacles as much as possible, such as ladders, brackets, pump valve equipment, etc.If it cannot be avoided, the false echo can be filtered out through program adjustment.The transducer should be perpendicular to the surface of the measured medium to ensure that the reflected echo signal can be received.In addition, there must be a sufficient distance between the transmitting surface of the transducer and the maximum liquid level, and the maximum liquid level must not enter the measurement blind area.
Precautions for installation and use of radar level gauge
Precautions for installation of radar level gauge: The measurement range is calculated from the point where the beam touches the bottom of the tank, but in special cases, if the bottom of the tank is concave or conical, it cannot be measured when the level is lower than this point.If the medium has a low dielectric constant, when it is at a low liquid level, the bottom of the tank can be seen. At this time, to ensure the measurement accuracy, it is recommended to set the zero point at the position where the lowest height is C.Theoretically, it is possible to measure the maximum position of the antenna, but considering the influence of corrosion and adhesion, the final value of the measurement range should be at least 100mm away from the maximum of the antenna.For overflow protection, a * distance can be defined to be added to the dead zone.*Minimum measurement range is antenna dependent.Depending on the concentration, the foam can both absorb microwaves and reflect them, but under certain conditions it can be measured.
Matters needing attention in the use of radar level gauge:
1. The measurement range of the radar level gauge should be calculated from when it touches the beam, but if the tank bottom of the radar level gauge is concave, it should be calculated from its lowest point.
2. Pay attention to the dielectric constant of the medium when using it. If the medium is of low dielectric constant, when it is at a low liquid level, it is best to set the zero point at the position where the lowest height is C, so as to obtain better measurement accuracy.
3. The influence of corrosion and adhesion should be considered during the measurement. The final value of the measurement range should be at least 100mm away from the center of the antenna.
4. The antenna will affect the minimum measurement range.
5. Set a certain distance to attach to the blind area, which can play the role of overflow protection.
