Regarding the use of hydrogen fluoride

It doesn’t seem to be there; one can check the properties of hydrogen fluoride, as well as the pressure and temperature requirements specified by the customer, and then select the appropriate pipeline standards. Inconel 600 alloy is generally suitable, as it exhibits good resistance to hydrogen fluoride at temperatures below 600 degrees ； Monel alloy can also be considered, and special gaskets should be used as well.

Plastic products are used in laboratories; I’ve really never encountered them in engineering work

For hydrogen fluoride media, stainless steel can be used when the temperature is below 270°C, while INCONEL600 can be used when the temperature is above 270°C.

We use PFA tubes

The hydrogen hydride I have worked with used pipes made of 16Mn steel and PP material.

Some hydrogen fluoride manufacturers use plastic pipes directly, as they are cheap and can be replaced when damaged. It’s actually well-sealed, but not intended for high-purity applications. A regular plastic water pipe should suffice. For higher-end applications, stainless steel pipes or Monel alloy pipes can be used; materials such as polytetrafluoroethylene are also suitable.

I’ve learned a lot, but how can hydrogen fluoride be measured accurately?

The poster needs to clarify whether it is anhydrous HF or aqueous HF, as the temperature and other conditions vary; for example, in the case of anhydrous HF, seamless tubes are sufficient

Carbon steel is widely used in hydrofluoric acid at concentrations of 60–70% or higher; the temperature for anhydrous HF should not exceed 65 degrees. Acid that is not pressurized has less corrosiveness. Special care must be taken at concentration boundaries (60–65%), as dilute acids are highly corrosive. According to test results, the corrosion rate of carbon steel in 93% acid at 20 degrees Celsius is 0.9 mm/year, while in 48% acid it is 13 mm/year. Low-carbon steel has the best corrosion resistance. Some storage tanks can last for over 10 years. All types of stainless steel are not suitable for use with hydrofluoric acid at any concentration, even at room temperature, as hydrofluoric acid can destroy the protective layer on the surface of stainless steel. There is only one exception: at room temperature, stainless steel can be used for handling anhydrous hydrogen fluoride. Generally, stainless steel is not used for dealing with fluoride solutions. If dilute hydrofluoric acid contains nitric acid or other strong oxidizing agents, this can reduce the corrosion of stainless steel. High-alloy stainless steel exhibits good resistance to gaseous hydrofluoric acid, as well as to anhydrous hydrogen fluoride. However, caution is needed when using it with acids with a concentration of less than 60%. Some factories use this material to manufacture pumps, valves, nozzles, etc. However, using this lining material is not economical; it is only employed in special cases, such as mixtures containing hydrofluoric acid and nitric acid, as well as crude phosphoric acid containing hydrogen fluoride

One is to check the temperature, and the other is to check the concentration. At low temperatures, plastic can be used; PTFE lining is also an option. At low concentrations, either plastic or stainless steel can be used. There is a lot of relevant information available on forums, with very comprehensive explanations.

For AHF, seamless carbon steel pipes are sufficient; if HF is present, fluorinated-lined pipes should be used

Anhydrous hydrogen fluoride is handled using hydrofluoric acid made of 16Mn steel together with PP pipes!

20%–30% hydrofluoric acid, below 150 degrees Celsius: polypropylene, vinyl fluoride, lined with copper; 30–60% nickel alloy, Hastelloy, anhydrous hydrofluoric acid, ordinary seamless carbon steel. For HF gas at temperatures above 250 degrees Celsius (anhydrous): grade 20 boiler steel. For low-temperature gases: ordinary carbon steel. For gases at temperatures above 400 degrees Celsius: Monel. Give it a bonus!

HF seems to belong to the GC1 category of pressure pipelines. . . You can look up the relevant design specifications for pressure pipelines. For example, the \"Code for Design of Industrial Metal Piping\" and so on. Our design institute completed the design of this project before the New Year; I’ve been working here for only a short time and don’t know much about it yet. . I’ll go to the clinic tomorrow to check it for you. I’ll tell you then. .

For high-purity materials with a water content of less than 300PPM, thick-walled carbon steel pipes can be used; for those with a higher water content, pipes lined with PTFE made from equivalent steel can be employed; and for applications involving high temperatures, Inconel 600 can be used.

It is best not to use stainless steel for HF, as it is prone to corrosion and the formation of green chromium salts. The service life is reduced.

Installing a weight sensor on the HF storage tank allows for weighing.