What about the valve? First of all, we should know what kinds of valves there are. Because the valve is a pressure pipeline container, the general manufacturer of the valve must have the People's Republic of China (PRC) Special Equipment Manufacturing License issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China.
As you are just beginning to learn, I will tell you about the classification of valves. You can mainly get a "People's Republic of China (PRC) Special Equipment Manufacturing License", which will indicate the business scope, generally five categories: gate valve, globe valve, ball valve, check valve and butterfly valve. There are other filter valves, pressure reducing valves, diaphragm valves and so on, many, many.
Generally, gate valves start with z, globe valves start with j, butterfly valves start with d, check valves start with h, and ball valves start with q.
For example: butterfly valve: D343H- 16C-400mm, which is a double eccentric butterfly valve with a worm gear drive flange with a diameter of 400mm and a cast steel sealing surface.
Where d stands for butterfly valve, the first 3 stands for worm gear transmission, 4 stands for flange connection, the last 3 stands for double eccentricity, H stands for stainless steel sealing surface material, 16 stands for pressure 16 kg, 1.6MPa, C stands for cast steel of valve body, and 400 stands for caliber.
Friend, I recommend you to read some books about valves. You'd better ask the manufacturers directly for their product atlas. Universal valves, positive valves, Huaxia valves and so on are recommended.
In short, learning valves is a process of long-term accumulation of experience. If you don't understand anything, you can leave me a message, and I am willing to make progress with you.
I hope my answer is useful to you, and I wish you a good mood every day:)