There is disclosed a container processing machine comprising a material handling surface for handling a sheet-like material through suction and a vacuum source in fluid connection with said material handling surface, the machine including means for detecting and transmitting a value of pressure of the gas being suctioned; a controllably operable flow valve; a control unit operatively connected with said detection and transmission means and with said flow valve; said detection and transmission means and said flow valve being arranged between said vacuum source and said material handling surface; said control unit being programmed to adjust the degree of opening of said flow valve in response to a signal which is a function of at least said value of pressure.