Introduction As we all know, the first fire engineers certificate is the construction industry in China, the gold content of the practicing certificate, in order to help you successfully pass the first fire engineers exams, obtain a certificate, I organized a fire engineers, "comprehensive ability" high-frequency points: fine water mist extinguishing, I hope to help you.
Examination of a system composition
Composition: pressurized water supply equipment (pumps or bottles), the system pipeline network, partitioning control valves, fine water mist nozzles and automatic fire alarm and linkage control system.
In order to prevent clogging of the fine water spray nozzle, there is a filter. In order to facilitate the normal use of the system, repair and maintenance, the system also has a drain valve.
Water mist fire extinguishing system in accordance with the distribution network of the pressure of the flowing medium can be divided into high-pressure systems, medium-pressure systems and low-pressure systems; in accordance with the type of flowing medium can be divided into a single fluid system and dual-fluid system; in accordance with the installation method can be divided into on-site installation and pre-installation system.
In accordance with the use of fine water spray nozzle type, can be divided into open system and closed system; according to the system water supply (mainly in accordance with the type of drive source), can be divided into pump group, bottle group and other forms, the current product is mainly pump group and bottle group two types
Examination of the valve group of the incoming inspection
1. >1. Operational performance inspection requirements:
Control valve valve and operating mechanism is flexible, no jamming phenomenon. Valve body clean, no foreign matter blocking. (Test pump, pressure gauge)
2. System installation of major components
Partition control valve installation height should be 1.2 ~ 1.6m, the distance between the operating surface and the wall or other equipment should not be less than 0.8m.
In the pressure regulator valve on both sides of the pressure side of the pressure side of the water supply equipment, the pressure side of the valve should be installed pressure gauges automatic control of water pressure side. Pressure gauge measurement range should be 1.5 ~ 2 times the working pressure of the system.
Exam point three pump installation requirements
1. Welding or bolting method directly installed in the pump base, or the pump set with bolts connected to the angle iron frame. The pump set suction pipe on the reducer is connected with eccentric size head.
2. The type and installation of the coupling between the high-pressure pump and the main engine meet the manufacturer's requirements, and the rigidity of the base ensures the coaxiality requirement.
3. When the system uses a piston pump, the pump unit needs to be filled and the oil level in the crankcase checked after installation.
4. Control cabinet and the base of the diameter of not less than 12mm bolts, each control cabinet not less than 4
only bolts; control cabinet base of the level of error is not greater than ± 2mm, and do anticorrosion treatment and waterproofing measures; do the upper and lower control cabinet inlet and outlet, do not destroy the control cabinet's level of protection.
Examination point four air pressure test
1. Test requirements:
The test medium is air or nitrogen.
Dry and pre-action system test pressure of 0.28MPa, and stabilized pressure for 24h, the pressure drop is not greater than 0.01MPa.
The test pressure of the two-fluid system gas piping for the hydrostatic strength test pressure of 80%.
2. Method of operation: the use of pressure test device for the test, visual observation of the pressure gauge pressure drop. System pressure test process, the pressure drop exceeds the provisions of the test, stop the test, empty the pipe network of gas; eliminate defects, retest.
Examination point five pipe network blowing
Blowing requirements:
Blowing with compressed air or nitrogen.
Blowing pressure is not greater than the design pressure of the pipeline.
Purge gas flow rate is not less than 20m/s.
Exam point six monthly inspection content and requirements
1. Check the appearance of the system components for collision deformation and other mechanical damage.
2. Check the partition control valve action is normal.
3. Check that seals or chains on valves are intact and that valves are in the correct position.
4. Check that the water level in the storage tank and water storage container and the gas pressure in the gas storage container meet the design requirements.
5. For the closed system, the use of water test valve on the action signal feedback test, observe whether the normal action and display.
6. Check the appearance of the nozzle and the number of spare meet the requirements.
7. Check whether the manual operating device shield, seal and other intact.
Exam point 7 pumping unit connection leakage fault analysis
1. Loose connection (tighten)
2. Connection 0-ring seal or gasket damage (replacement)
3. Failure cause analysis
1. Pump set test valve is not closed. (Close)
2. Pump set inlet power reverse phase. (Adjust the phase sequence of incoming power)
3. High pressure pump is damaged. (Replacement)
4. Use flow rate exceeds the rated value. (Work within the rated value of the pumping unit)
Exam point nine regulator pump frequent start fault cause analysis
1. Piping has a leak. (Repair leak)
2. Safety relief valve is not sealed well. (Overhaul)
3. Test valve not closed. (Close completely)
4. Impurities stuck on check valve gasket. (Clean one-way valve and clean water tank and piping)
The above is a small editor for you to bring the "level of fire engineers," high-frequency comprehensive ability "points: fine water mist extinguishing", I hope to help you. If you still want to know more important knowledge points of the fire engineers exam, pay attention to small timely push.