Based on my investigation, they are using CNC lathe with milling functionality. The first video shows the actual manufacturing process (partial). The second video will show the simulated full process. (1/2)

(2/2)

Sources 1: 2:

This is kind of incredible that this question made it around the world to the actual manufacturer of the part.

lol, the original video on douyin (Tiktok China) was actually made and uploaded by which is the manufacturer of *the device* for manufacturing the part, not the direct manufacturer of the part.

This is called a Swiss Lathe btw

100% correct, this is called a Swiss type Lathe.

Ripped off CNC lathe made for the Chinese Domestic Market with IP stolen from Citizen. Probably a pirated copy of Partmaker (from Autodesk).

NOTE: two videos are not uploaded by the same account. The second software video was uploaded by an education-related account.

Ah, so it is a demo file from the maker of the lathe/mill. That explains why we are seeing it so cheap on Ali, the factories are running it in idle time (Chinese factory maxim is you must never be idle, better to make headphone cable fishes).

no no no, there are many companies massively produce the impellers and sell them for USD 0.3/pcs (RMB 2.2/pcs) in China.