Changes in the pressure on the pressure gauge at the outlet of the radiation feed pump during winter
Thread Content
It is cold in winter; the outlet pressure of the coking radiation feed pump is 4.3 Mpa, and the pressure in the pressure gauge connection tube was also 4.3 Mpa before it froze. After freezing, the pressure on the pressure gauge gradually increases, often exceeding 10 Mpa; in several instances the pressure gauge even broke. What is causing such high pressure on the outlet pressure gauge, and how can this be resolved? Thank you
The reason for the increase in pressure is that the liquid inside the pressure gauge tube gradually condenses into a solid state, causing its volume to increase. Since the volume of the pressure gauge tube itself does not change, the volume from the point of solidification to the pressure measurement point is progressively compressed, which leads to an increase in pressure. As a result, the pointer of the pressure gauge went beyond its range and got damaged; in more severe cases, the pressure piping expanded and ruptured, leading to accidents!
Reply 1# qshzrz: Why would the pressure gauge at the outlet of the radial feed pump freeze? Was too much water added to the antifreeze coolant? Volume expansion occurs only when water freezes. If the oil solidifies, its volume will only decrease. The ratio of glycerin to water must be carefully controlled to ensure that the freezing point of the mixture is below the ambient temperature; alternatively, pure glycerin can be used as the isolation agent. It is extremely dangerous for such conditions to occur in high-temperature and high-pressure areas, as it can easily lead to accidents. Furthermore, when installing the pressure gauge isolation tank, try to minimize the distance between it and the process pipes; also, shorten the short pipe between the pressure gauge adapter and the valve as much as possible.
Reply to 3# waw0423: Our pressure gauges don’t have isolation tanks; they are installed directly, and there is no glycerin or moisture inside!