What are the valves used in soda production?

Today, I specially consulted the director who works in the ammonium chloride workshop, my master. He said that the mother liquor pipeline now uses ammonium chloride: 1. Stainless steel pipes; 2. Nylon tube (slightly more expensive than the next two); 3. steel-lined PO pipe; 4. PE tube with spring (made of all kinds of waste tires). Stainless steel is used for high-temperature liquid, and other pipes are used for pipes with liquid at room temperature. Valve: plastic film valve, that is, cast iron or carbon steel, lined with corrosion-resistant materials. There are also various DC rubber-lined valves, as well as plug valves and ball valves. Of course, stainless steel pipes are equipped with stainless steel valves.