Material selection for pure water tanks and other aspects
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Hey everyone: There’s now a pure water tank design with a capacity of 50 cubic meters. The water temperature can be either at room temperature or at 65°C. Pure water is used in the reaction process, and high standards are required for it. I’m not sure whether to choose 304, 316, or PE for the material. For PE, with such large containers, it’s fine at room temperature; but at 65°C, might its strength become insufficient? Do 304/316 require internal polishing? Should I still not do anything about it? I recently saw a equipment manufacturer, and I noticed that 304 equipment is subjected to sandblasting after it’s manufactured. As far as I remember, carbon steel equipment is painted after sandblasting; but if stainless steel equipment is sandblasted, doesn’t that destroy its passive layer on the surface?
The medical industry uses 304 sterile water tanks; the industrial sector uses PE, while in the food industry, items that come into contact with human consumption must be made of stainless steel
If, as you say, the stainless steel tanks in the pharmaceutical industry are all polished, then what should be done? ? :lol:lol
Do the forum members have any other suggestions?
It depends on whether it is to be used in the pharmaceutical/food industry or the chemical industry; generally, 304 or 316L materials are used, with a polished finish. We have manufactured many devices for similar applications
Thank you for your reply. I would like to ask, what is the main purpose of internal polishing?
For food/pharmaceutical equipment, GMP requirements mandate polishing; in the chemical industry, this is done to prevent materials from sticking to the walls
Stainless steel can be used to create corrosion-resistant internal coatings
Using fiberglass directly is convenient, practical, cost-effective, and food-grade options are available.
Looking at different industries, the highest requirements are in the electronics industry; stainless steel may not be suitable. The food industry has low requirements, so stainless steel can be used directly. Sandblasting is mainly used to remove surface contaminants, but it results in roughness; polishing is slightly better than sandblasting