| 摘要 |
FIELD: fire-fighting facilities.SUBSTANCE: invention relates to the field of fire extinguishing. The system of foam proportioning comprises a foam pump, a pipeline for foam, a discharge device and a controller. The pipeline for foam is in fluid communication with the discharge pipeline and the foam pump. The discharge device has a recirculation line. The recirculation line has a first end which is located downstream of the foam pump, and a second end which is located in front of the foam pump. The discharge device operates with the ability to direct the part of flow of liquid foam concentrate through the recirculation line. The controller is configured with the ability to actuate automatically the foam pump and the discharge device for maintaining a minimum flow rate of the liquid foam concentrate through the foam pump. The discharge device comprises a simple control valve which responds to a signal from the controller and opens automatically when a foam demand is less than the minimum flow rate.EFFECT: improvement of the design of the system.10 cl, 9 dwg |
