Pipe materials used in polysilicon production
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What materials are used for the pipes in polysilicon production? For example, what kind of pipes are used for transporting silicon powder, and what kind of pipes are used for transporting hydrogen, chlorine, etc.? If anyone knows, please share some information. This post was last edited by daniao59 on 2008-11-7 08:25
This question is phrased a bit vaguely; it’s best to clarify the medium, as temperature/pressure are very important
There are significant differences among various production stages
Carbon steel pipes will do; there are no special requirements, right? !
Our company uses carbon steel pipes, but it is required that the pipes be degreased.
Carbon steel is used for silicon powder transportation, 316L is used for hydrogen, and the material used for chlorine is not clear.
Of course it’s 317L; TCS and CL2 are highly corrosive, and H2 also requires 317L – this is essential. Moreover, cleanliness in polysilicon production is very important. As for silicon powder, carbon steel can be used.
For ordinary water systems where lower standards are sufficient, 304 stainless steel can be used. However, for applications such as electrodes and the cooling water used in power regulators, where high purity is required to prevent scaling and damage to the electrodes, 316 stainless steel is necessary. For other types of pipelines that involve media with high purity and strong corrosiveness, it is best to use stainless steel as well. If investment is substantial, companies like Xinjiang Ordos’ polysilicon production use all stainless steel for that purpose – that’s really impressive!
Just one suggestion: don’t use 304; carbon steel is much better than 304, based on experience.
On the 9th floor, is 304 better than carbon steel? How do you say this? Explain, 304 is actually stainless steel
316L is generally used for finished products； For previous semi-finished products, 316 or 304 is usually sufficient, as after all they are exposed to corrosive liquids ； For utility projects, ordinary carbon steel pipes are generally sufficient. As for plastic materials such as PVC, they are generally used in situations where corrosion resistance is required and the pressure level is not high.