Here’s a question to test you—to see how well you are at measuring liquid levels. I can send money; if you need 200, I’ll give 200, and if you need 2000, I’ll give 2000

If it works, I’ll pay money – 200 if that’s what’s requested, 2000 if 2000 is requested. To cheat you is like being a dog. . . Knowledge holds power; skills equal wealth. I’m a dog if I lie to you – if it works, I’ll pay money: 200 if that’s what’s asked, 2000 if 2000 is asked. Lying to you means I’m a dog. . . Knowledge holds power; skills equal wealth. I’m a dog if I lie to you – if it works, I’ll pay money: 200 if that’s what’s asked, 2000 if 2000 is asked. Lying to you means I’m a dog. . . Knowledge is power; skills bring wealth. I’m just a dog if I deceive your brother.

There is no mature solution yet; here are a few preliminary thoughts, offered as a starting point for further discussion: This type of testing is quite challenging – the installation holes are small, and the pressure and temperature levels are high and variable. As a result, many measuring instruments are not suitable for use. The ideal choices should be those whose sealing issues can be easily resolved, that meet the requirements of the installation holes, and whose performance is not affected by pressure and temperature within acceptable limits. 1. Initially, the internal floating bulb was a choice that met the requirements for mounting holes and sealing, but it is not clear whether the effects of density changes can be corrected. If the heating, pressurization, and testing processes are controllable, corrections can be made based on the corresponding temperature and pressure curves. If this doesn’t work, all other buoyancy types have the same problem. 2. Magnetostriction: Issues related to sealing and mounting holes need to be addressed. 3. Ultrasonic waves: Some manufacturers recently advertised that it can be used to measure the liquid level inside tanks (the one shown in the live broadcast); they were from Xi’an, I think. 4. Use two pressure transducers: one installed to measure the pressure at the bottom of the tank and another to measure the pressure at the top, in order to account for the effect of density and determine the liquid level. This is Pig Brother’s strength.

The storage tanks are of the top-mounted type. The factory primarily uses three types of level gauges: magnetostrictive level gauges, which are mainly used in waste tanks (for sewage, oily wastewater, rainwater) as well as in small storage tanks (such as those used for lubricating oil in the factory’s pump and fan lubrication systems); and radio frequency admittance level gauges, which are used for measuring the level in electrodesalination processes during atmospheric and vacuum distillation. The situation is similar to what was described earlier – there is high pressure of several megapascals; at the top there is gas and oil, in the middle there is crude oil, and at the bottom there is water, sewage, and sludge. At the bottom of the storage tank, there are many pumps driven by high-voltage electricity. The operating conditions are harsh; the equipment has to be shut down for manual cleaning almost every six months. I went inside to take a look, and I saw rows of metal motors covered with sticky, black, and foul-smelling sludge, and the shafts of the radio frequency admittance meters were also coated with such material. Internal floating ball level gauges were previously used in some zero-level tanks (mainly those for dirty oil during startup and shutdown), but their performance was very poor – they were almost never accurate – so they are no longer used. All three of the above instruments are of the top-mounted type; the flange area for installing the internal float is large, which does not meet the required specifications. For magnetostrictive sensors, since the float moves up and down on a rod, it is better not to use them if the medium contains impurities or is corrosive. Finally, radio frequency admittance is the option that can meet these requirements; however, it is difficult to say anything about its accuracy and reliability. The level sensors of the electrodesalination tanks in the plant occasionally malfunction; a common issue is a sudden change in the level – for example, it goes from around 30% to zero suddenly. The cause of this fault cannot be identified, so it cannot be resolved permanently. However, the problem is resolved once the power cable is disconnected and then reconnected. Over time, when this fault occurred, it was handled in that way. As for the issue of inaccurate calibration levels reported by the process technicians, it’s really impossible to carry out repairs, as it’s not possible to zero or calibrate the device during normal operation; adjustments can only be made based on what the technicians say. However, such adjustments only make the readings less accurate. In the end, the management decided that no further adjustments should be made – there’s no room for arbitrary changes. In the previous two years, the recovery rate of heavy oil from offshore oil fields in China was not high. In order to increase production, the upstream operators added a substance called polyacrylamide to the crude oil; this substance mixed with the crude oil, causing the oil and water within it to emulsify. As a result, it became difficult to separate the wastewater from the crude oil during electrodialysis, which led to failures in radio frequency admittance measurements. During that period, we had to work on fixing these instruments almost every day. It wasn’t until it became impossible to proceed that we realized the upstream operators had adulterated the crude oil, and only then did the process engineers stop using those instruments.

If you have the money, just use a gamma-ray level gauge

Thank you for participating. Radiometric level gauges – even those with enough money wouldn’t dare use them for this purpose. This testing equipment is used to study the degree of corrosion of materials under high temperature and pressure conditions; gamma rays can disrupt these testing conditions and affect the results.

Thank you for participating. Radioactive level gauges – even those with enough money wouldn’t dare use them for this purpose. This testing equipment is used to study the degree of corrosion of materials under high temperature and pressure conditions; gamma rays can disrupt these testing conditions and affect the results

Well, there are quite a few devices that cannot be opened, for which radar level gauges are used. Since it’s experimental equipment, it will disrupt the experimental environment; in that case, there’s nothing to do. Alternatively, a capacitive level gauge could be tried

Let’s talk about the ideas: The key to measuring this container lies in determining the measurement requirements. Requirement 1: Minimum requirement – alarm point for high liquid level measurement ； Requirement 2: Measure the actual liquid level; here too, there are issues. For Requirement 1, the solution is relatively simple – a transmitter with a low differential pressure (or micro-differential pressure) is sufficient. The positive-pressure tube should be inserted at the high alarm point within the container; when the liquid level is below this point, the transmitter reads 0, while when it is above this point, the transmitter reads a value greater than 0. It is possible to set a error range for making judgments. Installation is still quite difficult; it requires gas to be present inside the pressure guiding tube. There are two methods: 1) Use an isolator (a device that prevents liquid from entering, which needs to be properly designed). 2) Apply a slight backflow of high-pressure nitrogen (such as from a high-pressure nitrogen cylinder); the amount used is very small. For requirement 2, it is even more complex; 2 differential pressure transmitters are needed, and the density and liquid level can be determined through calculations. The key issue is that it’s relatively difficult to install. The principle is similar to that in Requirement 1. Due to limitations on the equipment openings, for positive-pressure services, the pressure tapping pipes are inserted concentrically into the vessel at different depths. Then connect to the positive pressure side of the transmitter separately. Negative pressure connection to the pressure gauge port (common). The pressure tap tube is required to be filled with nitrogen; the approach is the same as in requirement 1 (omitted). I have tried this concentric insertion method, and it works well. Of course, some details need to be considered in the actual implementation process; since the conditions of the operation and control process (such as pressure and temperature changes) are not specified in detail, they will not be discussed here.

Let’s talk about the ideas: The key to measuring this container lies in determining the measurement requirements. Requirement 1: Minimum requirement – alarm point for high liquid level measurement ； Requirement 2: Measure the actual liquid level. For requirement 1, the solution is simple: a transmitter with a low differential pressure (or minimal differential pressure) is sufficient. The positive-pressure tube needs to be inserted at the high alarm point within the container; when the pressure is below this point, the transmitter reads 0, and when it is above this point, the transmitter reads a value greater than 0. It is possible to set a error range for making judgments. Installation is still quite difficult; it requires gas to be present inside the pressure guiding tube. There are two methods: 1) Use an isolator (a device that prevents liquid from entering, which needs to be properly designed). 2) Apply a slight backflow of high-pressure nitrogen (such as from a high-pressure nitrogen cylinder); the amount used is very small. For requirement 2, it is even more complex; 2 differential pressure transmitters are needed, and the density and liquid level can be determined through calculations. The key issue is that it’s relatively difficult to install. The principle is similar to that in Requirement 1. Due to limitations on the equipment openings, for positive-pressure services, the pressure tapping pipes are inserted concentrically into the vessel at different depths. Then connect to the positive pressure side of the transmitter separately. Negative pressure connection to the pressure gauge port (common). The pressure tap tube is required to be filled with nitrogen; the approach is the same as in requirement 1 (omitted). I have tried this concentric insertion method, and it works well. Of course, some details need to be considered in the actual implementation process; since the conditions of the operation and control process (such as pressure and temperature changes) are not specified in detail, they will not be discussed here. For discussion only!

Stop it, ultrasound can only be used at normal temperature and pressure.