Valve selection..... Seeking advice
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The medium is fluorite in the form of fine particles, with a temperature of 180°C. Dear experts, what type of valve is suitable for use in industrial applications like this? The diameter is DN200 and the pressure is 0.5 MPa; a pneumatic butterfly valve would be the appropriate choice. Ceramic, polyurethane, Stellite surfacing, fluororubber, and silicone have been used. Overall, alloys and ceramics were used for up to 1 day. The lifespan of fluororubber is similar to that of silicone, around 3 months. Polyurethane meets the requirements in terms of wear resistance, but its temperature tolerance is not good.
What are the reasons why this alloy doesn’t perform well? The hardness of fluorite isn’t high! Also, I would like to know what the hardness of polyurethane is. If I’m correct, then you’ve made a wrong choice in selecting this material!
What are the reasons why this alloy doesn’t perform well? The hardness of fluorite isn’t high! Also, I would like to know what the hardness of polyurethane is. If I’m correct, then you’ve made a wrong choice in selecting this material!
The medium is granular, so the valve must have wear resistance; otherwise, it is prone to sealing leaks (internal leakage). The temperature of 180°C is not high. I suggest that ceramic pneumatic butterfly valves would be ideal. Ceramic valves are resistant to wear, high temperatures (T≤500℃), corrosion, and erosion; they also have good thermal insulation properties, low expansion, and high hardness (second only to diamond). As you said, I don’t quite understand how a ceramic valve can only last for one day. The media used in ceramic valves are those containing particles; may I ask how large these particle sizes are?
I’m not sure what the size of the crystal particles you use are. When selecting products for our clients, in the powder handling industry we generally opt for gate valves; you might consider gate valves that have no dead zones. Many of our clients in the powder handling industry use such valves
Reply to 2# wow0011: The alloy comes out directly through a hole in the valve body. I checked some information and found that fluorite has a low hardness, but I still don’t understand why it can’t be used in ceramics or alloys. But is it really a wrong choice of model? However, the same powder works well for polyester-based polyurethanes (AU) when the temperature is below 100°C. Whether it’s domestic or Eboro.
Reply to 4# cevalve: On the ash transfer pipelines in steel mills, I also use ceramic ball valves, and they work very well. However, ceramic butterfly valves have only one sealing surface that is lined with ceramic, while the back side is coated with a wear-resistant coating. The ceramic sealing surface is subjected to pressure and erosion, but the problem lies in the coating on the back side, or it perforates. In your opinion, what is the cause of the problem with ceramic butterfly valves?
Coming out of the valve body? It’s really hard to figure this out. If it comes out of the valve body, that means it’s breaking through the valve body; then the pressure difference or something similar must be at play, otherwise this situation wouldn’t occur. Is there maybe something else in the medium as well?
Reply to 6# swice, OP: You mentioned passing straight through the valve body – is it a sealing leak or is the valve body itself punctured by debris?
I suggest you try PTFE. Use software for sealing combinations/software or hardware/software; avoid a head-on approach
With the development of valve technology to date, in applications requiring wear resistance, ball valves represent a relatively ideal choice. Because the sealing surface of a ball valve is always closed, in other types of valves such as gate valves, globe valves, and butterfly valves, the sealing surface is exposed to the medium when the valve is in a partially open or fully open position. This is also why metal hard-sealed ball valves are widely used in the coal chemical industry and mining industries.