摘要 |
<p>This invention concerns a system for insuring and accurately controlling the turbulent flow of a pressurized mixture of a gas (14) and a cleaning fluid (12, 10) for purging and cleaning ducts. The pressures of cleaning fluid (12, 10) and the gas (14) are continuously sensed and transduced into electrical signals for controlling valves for the pressurized gas (14) to maintain and insure its pressure at a predetermined amount relative to the pressure of said cleaning fluid (12, 10) so that when the gas (14) and fluid are mixed in a turbulator (20), turbulent flow is insured. The improvements of this circuit include a pressure sensor transducer (52) for sensing the pressure of the input of the air (14) to the turbulator (20) and feeding it back to the main air pressure transducer (52) for accurately maintaining a predetermined ratio between the gas (14) and cleaning fluid (12, 10) pressures within less than about 1 psi in at least pressures of 150 psi.</p> |