The so-called industrial fluid on the extremely low temperature, generally refers to the boiling point in atmospheric pressure - 50 following the fluid.

Representative of a very low temperature fluid LNG (liquefied natural gas), LN 2 (liquid nitrogen), LO 2 (liquid oxygen), liquefied ethylene, liquid hydrogen, liquid chlorine and these low-temperature gas, L PG (LPG) does not include In a very low temperature of the fluid.

On a very low temperature in the fluid flow measurement methods, in particular to understand the industry is in the process of using these fluids, it compared with the normal temperature or heat What are the different ?What kind of problem-prone? So, first of all give a very low temperature fluid And to illustrate the characteristics of the process.

(1) easily lead to changes in state

Pose a very low temperature of the fluid material with Table 1, Table 2 shows the physical constants. These are usually saturated fluid stored in the insulation of storage containers. Boost pumps used, sent to begin the process handling, and repeated compression and decompression. During this process, the saturation point while the very low temperature fluid into the cold, and later into a state of boiling, the state easily change. Therefore, the piping design and flow meter design need to take measures.

Table 1 low boiling point of the physical constants of material