(I) Strengthen maintenance
From a macro perspective, property management and maintenance operators should first be familiar with the overview and types of high-rise building water supply systems, master the performance characteristics of different building life water supply systems, fire protection systems and even production and other composite water supply systems, and have a basic understanding of the system hydraulic balance operation mechanism and setting technical conditions. In particular, they should be familiar with the application principles and performance requirements of various pressure reducing components in the system. It is necessary to master the normal performance indicators of the system. When the system fails, such as the unstable pressure of some water-using equipment, rapid fluctuations, and even accompanied by negative pressure suction, or intermittent whistling noises in the key pipe sections of the pressure reducing system, they should not only be able to analyze and judge the reasons from a rational perspective, but also guide practice with correct ideas; at the same time, they should strengthen the sense of responsibility for maintenance and management, improve the professional and technical level, and cultivate the hands-on ability of system debugging, operation and emergency troubleshooting. Manage the water supply and water facilities of each high-rise building well to benefit the owners (users).
(II) Operation
1. Avoid leaving dirt and debris into the pressure reducing valve pressure reducing guarantee system. The pipe network of the pressure reducing system of the newly built or renovated project is likely to have sand, hemp and debris left. Before commissioning, it should generally be flushed with water. After meeting the cleaning requirements, the pressure reducing valve and filter element should be installed at last to avoid the flow of debris into the pressure reducing valve and prevent the pressure reducing valve from getting stuck. After the system is put into operation, whether the water flow of the pressure reducing system is smooth or not is closely related to the flow capacity of the filter installed on the system. If the filter element is seriously adsorbed by debris, it will affect the operation of the pressure reducing valve. Therefore, it is necessary to check the filter regularly and remove the dirt in time. Practice shows that this work must be done once every 2 to 3 months. Some adjustable (spring type, membrane type) pressure reducing valves have filters set on their main valves or pilot valves, and the filter elements also need to be regularly disassembled and cleaned.
2. The pressure reducing valve group used in reserve should be rotated regularly. The pressure reducing guarantee system of most high-rise building life water supply pressure reducing valves is set up in vertical water supply partitions, and is generally set on the main pipe of each water supply partition. Considering the reliable and safe water use of many users (there are dozens to hundreds of households in each residential area, and dozens of guest rooms in each area of public buildings such as hotels and restaurants...), two sets of pressure reducing valves should be installed in parallel during design (one for use and one for backup). Gate valves or butterfly valves are provided on both sides of the pressure reducing passage to open and close any pressure reducing passage. In order to ensure the normal operation of the two parallel pressure reducing valve passages, they are usually exchanged once a month. If they are left idle for too long, the dead water in the pressure reducing passage will scale, and the valve core of the pressure reducing element will get stuck and fail.
3. The accumulated gas in the pipeline should be removed in time. When air enters the pressure reducing pipe network or the gas is precipitated from the water as the pressure changes in the pipe network, the water pressure of users in the area is extremely unstable; the pressure of the water user at the most unfavorable point of water supply changes rapidly, sometimes showing a false peak pressure, sometimes pumping and cutting off the water, and the pipe network will be accompanied by a knocking sound. This phenomenon will affect the stable operation of gas water heaters, electric water heaters, etc., and in serious cases, they will be destroyed; it is also very destructive to the water inlet connection pipes of various washing utensils, so pipe bursts occur frequently; some water meters cannot measure correctly, and the water meters will continue to rotate even if the user does not use water. In order to prevent such accidents, it is necessary to check whether the water storage elevation of the roof water tank life water supply main pipe is sufficient. If it is not satisfied, water vortex will be generated at the water outlet of the water tank and air will be sucked in. To eliminate this fault, the lowest water level elevation of the liquid level controller in the water tank can be adjusted. Experience shows that the lowest water level should generally be no less than 0.3m from the water outlet. You can also repeatedly open the pressure gauge venting cyclone set on both sides of the partition and pressure reduction system to slowly discharge the air that has entered the pipe network. If the above measures are taken, some water appliances below the end of the partition main pipe still have the above phenomenon, automatic exhaust devices can be added to these parts.
4. Pay attention to the pressure reduction guarantee system of the pressure reducing valve. Whether a proportional or adjustable pressure reducing valve is selected, the pressure reducing ratio P1:P2 should not be too large, and should generally be controlled within 5:1. Exceeding this range is prone to cavitation, damage to valve parts, and whistling noise. For some piston pressure reducing valves, the manufacturer processes a small hole with a diameter of about 1.5mm on the valve body. Its function is to allow the valve core to play a role in air permeation when it moves. During maintenance and management, care should be taken not to plug the small hole, otherwise it will affect the normal operation of the pressure reducing valve.
5. Strengthen the management and inspection of the pressure reducing valve guarantee system, and pay attention to the working dynamics of the pressure reducing valve itself. The pressure values before and after the valve are close, indicating that the pressure reducing valve itself has a fault. That is, the plane sealing rubber parts between the valve core and the valve body of the piston pressure reducing valve are damaged; the main valve diaphragm of the membrane adjustable pressure reducing valve has cracks and the O-ring is damaged, and the pilot valve connecting pipe is blocked, causing the pressure reducing effect of the pressure reducing valve to be weakened or fail. This is extremely harmful to the partitioned pipe network, especially many water-using equipment may burst due to overpressure, which must be repaired in time. If the air-inhaling holes on the valve body of the proportional (piston) pressure reducing valve continue to drip, it indicates that the O-rings on the valve core have been worn and the seals need to be replaced. However, when repairing and disassembling the pressure reducing element, be cautious and careful, and replace the internal seals; when cleaning up debris, you should take advantage of the situation and do not use metal rods or hard stems to pry the moving parts of the valve. Use a wooden hammer and a wooden handle to knock and vibrate, and slowly disassemble the internal parts of the valve. When reinstalling after the repair is completed, it must be consistent with the flow direction indication on the valve.
6. Pay attention to check the installation position of the proportional pressure reducing valve. If the design and installation position of the pressure reducing valve in the high-rise is not appropriate, the pressure after the pressure reducing valve will fluctuate, and the pipe network pressure will seriously deviate from the allowable range, accompanied by the destruction of the shower, the bursting of the water pipe and the damage to the user's water meter. Sometimes the water flow is not smooth, and there will be irregular water outages in the partition, affecting the user's water use. When a similar accident occurs, check the entire pressure reducing valve pressure reducing zone water supply system, and no doubts can be found; dismantle the pressure reducing valve filter and other components without abnormalities; some property management units even doubt the technical performance of the pressure reducing valve, and replace the new pressure reducing valve many times, but the problem cannot be solved. At this time, you can start by checking whether the design and installation position of the proportional pressure reducing valve is reasonable, and carefully check whether there is an equal-position inverted siphon phenomenon in the pipe network system, that is, the output pipeline elevation of the zone is similar. This kind of situation is easy to occur in the same roof water tank and water supply system of the main and auxiliary buildings. If these problems are found, you can consider raising the installation position of the proportional pressure reducing valve to a higher level (not too high, and the pressure-bearing specifications of the water-using equipment in the zone must be taken into account); you can also set up two independent proportional pressure reducing valve water supply systems in the main and auxiliary buildings.