The first step: the internal leakage of the gate valve, the energy consumption calculation first "knows". The daily energy consumption calculation of the device shows that today compared to yesterday, the raw materials are the same. If the yield drops, I will preliminarily judge that there may be internal leakage in the gate valve, which will increase the energy consumption.

The second step: the thermometer detects "indispensable". If the gate valve leaks, the temperature of the adjacent subsequent pipelines will be significantly increased or decreased as detected by the thermometer.

The third step: the stethoscope "keep up". We have determined the internal leakage of the gate valve through the first and second steps of inspection, but it has not been fully confirmed. At this time, the "stethoscope" test is very important. You can choose a screwdriver as a "stethoscope". Place one end of the screwdriver head perpendicular to the pipeline and the other end close to your ears. Listen carefully to see if there is any abnormal noise in the pipeline. If so, you can judge that the gate valve is leaking.

According to these three steps, it is basically possible to accurately determine whether the gate valve has internal leakage! In addition: attach an article on how the temperature is used to identify endoleaks.

The method to determine the internal leakage of the valve is: 4-6 hours after the valve is closed, use an infrared temperature measuring instrument to measure the temperature of the valve stem (near the valve body) or the metal temperature 150mm downstream of the valve body. If it is greater than 70℃, it is regarded as "internal leakage". ". This judgment method is applicable to most internal leakage valves, but in actual work, we encountered the following special situations: side-by-side access to the drain or drain gate of the drain and discharge pipe, when the last valve position is equal When close to the main pipe, as long as any branch valve in the pipeline leaks, the temperature of other valves will rise to more than 70℃, such as boiler blowdown valves, superheated steam drainage, etc. Therefore, other methods should be used to determine the internal leakage of these valves, generally measuring the temperature of the pipe wall in front of the door or the temperature of the valve stem in front of the door to determine the internal leakage.

     Judgment criteria for valve internal leakage (temperature) medium temperature

     Severe internal leakage of pipe wall temperature behind the drain valve

     ＞500℃

     ＞250℃ and the temperature difference with the pipe wall in front of the door is less than 50℃

     ＞200℃ and the temperature difference with the pipe wall in front of the door is less than 50℃

     ＞150℃ and the temperature difference with the pipe wall in front of the door is less than 50℃

     ＞120℃ and the temperature difference with the wall of the pipe in front of the door is less than 30℃

     General endoleak

     ＞200℃ and the temperature difference with the door tube wall is less than 80℃＞150℃ and the temperature difference with the door tube wall is less than 80℃＞100℃ and the temperature difference with the door tube wall is less than 80℃＞80℃ and the temperature difference with the door tube wall is less than 50℃

     leakage

     ＞200℃ and the temperature difference with the front pipe wall is greater than 50℃＞150℃ and the temperature difference with the front pipe wall is greater than 50℃＞100℃ and the temperature difference with the door pipe wall is greater than 50℃＞80℃ and the temperature difference with the door pipe wall is greater than 50℃

     400℃-500℃

     300℃-400℃

     150℃-300℃