1, Qingdao Yongtai boiler used to be a boiler, but the steam recovery machine developed by Pingdu later seems to have been copied by many people.

It should be in a place like Tonghe Industrial Park;

2. Dehong Thermal Power = Qingdao Dehong Thermal Power Equipment, and the boss's surname is Wang, which is quite refined and has a bad reputation.

It doesn't seem to be doing very well now. The factory moved to the west outer ring of Pingdu. Last time a friend said it moved again. I don't know what happened. Now the website can't be opened. Probably quit.

3. Qingdao Venus should be from Jiaozhou. It is said to be a reducer. Small factories don't know much about it.

You'd better ask those in Linyi. Probably not much better.