What are heavy tracing and light tracing for instrument heating?

It can also be divided into hot water heating, steam heating, and electric heating

This post was last edited by HEJIYUER on 2020-2-14 00:44. Both process and instrument pipes require either light or heavy heat tracing. It’s just that capillaries are now popular for instruments – they’re simply attached, and people don’t pay attention to the measurement principles, nor do the standards explain the scope of application. Heat tracing is a heat transfer process, and the physical properties of the medium need to be taken into account. For counterweights, the heating temperature is essentially equal to the surface contact temperature, which in turn is equal to the temperature of the steam; therefore, a high heat transfer rate can be achieved. Most instruments are of the light-type, as there is no flow of medium, and the heat required is to \"counteract\" heat loss to the environment. The purpose of heating the pressure guiding pipe is to maintain the phase state of the medium, preventing the liquid from freezing without causing overheating ； The gas does not condense at the operating pressure. Some insights: --- For steam, the measuring medium is condensate; the minimum temperature must be such that freezing does not occur, while the maximum temperature must be below the point at which vaporization takes place. Vaporization is impossible; therefore, it’s sufficient to maintain the bottom line, Light Companion. ---Butadiene-based liquids: the transition heating medium undergoes self-polymerization, with minor accompanying effects. ---Alkaline solution; anti-freezing measures. Excessive heat tracing accelerates material corrosion; use mild heat tracing instead. ---Benzene, antifreeze, Light Companion. ---For heavy oil/residue, it is beneficial to heat the medium to a certain \"low\" viscosity in order to facilitate pressure transmission. Because a higher heating temperature is required, heavy companion. The gas used for measurement is generally a light hydrocarbon, as conventional heating steam operates at temperatures of 130–150 degrees, which is more than sufficient to keep the gas in gaseous state; it is even possible to heat light hydrocarbon liquids into gas for measurement purposes. If a gas requires a temperature of over 60 degrees to remain in the gaseous state at operating pressure, it will condense at ambient temperature; in such cases, when measuring liquids instead of gases (steam being an example), heating may not be necessary at all. The higher the temperature that needs to be maintained, the greater the requirements for construction and maintenance.