Maintenance of magnetic flap level gauges
Thread Content
The magnetic float level gauge is a type of level measuring device that offers easy visualization and simple maintenance. Unlike glass plate level gauges, it doesn’t get dirty easily and makes it possible to see the level clearly; moreover, it’s not prone to breaking, making it safe to use. There are two issues at present: First, there are doubts about its accuracy in normal operating conditions – how do you address this? Are there any good, simple solutions? Second, when measuring substances that are prone to freezing, heating is required; what kind of insulation method is used? Is the entire device insulated with only a panel left at the front?
1. When there are doubts about the accuracy of the process, first compare it with the glass plate level gauge, and then drain the liquid inside the magnetic float in the same way as when observing the glass plate. Check whether the on-site signal is the same as the remote signal, and identify the issue one by one. 2. The heating mixture should be prepared based on the local temperature and the properties of the medium. Try to prevent the medium in the tank from vaporizing. Generally, mixing it half with hot water is sufficient.
Generally, impurities in the medium being measured will adhere to the float, causing it to stick and affecting the measurement.
When performing maintenance, we usually use a magnet to try to move it; if it moves, then we lift it up and down. If it can return to its original position, it means there is no problem with the level gauge
1. Remote transmission level gauges such as electric float level gauges and magnetic flap level gauges are generally installed at the site. The readings of other instruments can be used as a reference to determine whether there is a problem with the magnetic flip plate. The process allows the magnetic flap to be emptied for inspection. 2. Regarding the heat tracing issue for the corresponding magnetic flap, the properties of the medium being measured should be taken into account; it is sufficient to ensure that the liquid does not vaporize. Additionally, carbon steel tubes must not be used for the heat tracing pipes, as this will lead to inaccurate measurements.
It is usually due to a clogged float or reduced elasticity of the reed magnet. Insulation is generally in the form of semi-heating to prevent the liquid inside the magnetic float from vaporizing.
First, check whether the magnetic float is stuck; in winter, see if it has frozen. Second, use a proper screwdriver to probe the pipe in order to find out where the magnetic float is located. Third, if nothing is wrong with the above, then remove the reed switch and use a magnet to check if there are any issues with the 4-20mA signal. If everything is fine, then there’s no problem
1. First, check whether the column-flipping action is working properly; generally, this can be done by using a magnet to attract it. Next, check whether there is pressure buildup in the float chamber and whether any medium is attached to the float. If everything is normal, compare the readings with those of other instruments; if the differences remain significant, it is possible that the magnetic core of the float has lost its magnetism. 2. For heat tracing, a steam jacket can be considered based on the properties of the medium.
We usually contact the process operators; by using a magnet to attract the float, its location can be determined. To check whether the float is stuck, they are asked to close the root valve and drain the fluid from the level gauge, to see if the float returns to the bottom. After that, the root valve is reopened and the gauge is filled with fluid again, which allows us to determine if the float is stuck. If it is stuck, the level gauge needs to be removed to clean out any debris inside it.
The on-site display and remote transmission of the magnetic flap level gauge are two separate measurement systems; if the two values match, there is no problem. A common problem we encounter is that there are deposits in the tank, preventing the float from rising. Normal after waste discharge
1. Generally, we first compare it with other level gauges, and then use a magnet to lift the float in order to determine the liquid level. In the case of magnetic flap level gauges, inaccurate measurements are usually caused by impurities adhering to the float or the tank body, or by changes in the density of the liquid being measured. 2. For heating of magnetic flap level gauges, semi-heating is used; for insulation, a DN50 rock-faced pipe is employed, with only the panel exposed. Oilcloth is used to cover it, followed by applying a layer of paint, sticking glass fiber cloth onto it, and applying another layer of paint on top. :handshake
Everyone upstairs, have you encountered a situation where excessive heat from the heat tracing leads to a decrease in density inside the magnetic level gauge, causing the float to sink and resulting in an underreported level reading (compared to that of the pressure transmitter)?
Try it with a magnet; if there are problems, remove it to clean out the impurities, and replace the magnet if it has lost its magnetism