... 2, When welding, the four corners of tuyere bottom always can’t hold out against the mainboard meanwhile, what to do if ... increased about 10°C.3, What’s the function of “Air Regulator” button? The size of our tuyere is from 28mm to 46mm, in ... Air Regulator” button, it can decrease the rate of expanding bridge. Of course, the other method is to adjust the distance bewteen tuyere and chip properly, ...