Research On Standard Proportioned Equipment For Foam Fire Extinguishing System Testing

With the consideration of supply system of standard mixture used in thetest for foam generator and injection device, some research work onstandard proportion mixing equipment is done. This study mainlyincludes the whole schema, equipment design and calculation andvalidation of performance parameter. The results of this research willserve as the standard testing equipment directly used in foam generatortest and foam injection device test. The substantial conclusions areobtained in the present dissertation.1. The existing foam proportion mixing product are introduced, mainlyincluding in-line proportional mixing equipment, round-the-pumpproportional mixing equipment, balance proportional mixingequipment, direct injection variable pump output proportional mixingequipment and pressure proportional mixing equipment. Based on theprinciple and the advantages and disadvantages of foam proportionmixing products, the proportion mixing method used in foamgenerator test is proposed;2. According to the detection of different types of foam products,breaking through traditional design way, the general designing plan ofstandard pressure proportional mixing equipment used in foam fireextinguishing system test is raised. The specifications（DN50、DN100、DN150）of pressure proportional mixing equipment areconfirmed by comparing the main characteristics parameters（pressure range, flow range, mixing rate） of the fire extinguishingproducts. Then the connection modes of test device are proved andthe detail design is given through optimizing; 3. According to operating parameters range （pressure range, flow range,mixing rate）of pressure proportional mixing equipment, the size ofmain pipeline nozzle and throttle orifice used in three differentspecifications of proportional mixing equipment are calculated, andthe design parameters of installation way, installation gap and pipesize between proportional mixing equipment and foam tank arechecked;4. The foam extinguishing agent of different classes, different expansionand different mixing rate is test by spectrophotometer andconductivity apparatus. The curve graphs of absorbance versus timeand conductivity versus temperature are obtained. The mixedconcentration test method of foam is done, and the mixing ratio testmethod applied to evaluation of studying device is selected;5. The foam extinguishing agent used in standard pressure proportionalmixing equipment is tested in various pressure range and flow range.The mainly performance parameters and test parameters of standardpressure proportional mixing equipment are evaluated;6. The study on direct injection variable pump output proportionalmixing equipment is proposed and future research work is donethrough deeply analysis of above research results.