Fire water supplied by most fire sources requires a fire pump to pressurize it to meet the water pressure and water requirements of the fire. Pump set due to improper maintenance failure will inevitably affect the fire and rescue, causing unnecessary losses. Here, I encountered in the work of several fire pumps to talk about personal understanding of the issue, in order to find fault.

First, the multi-storey building is necessary to set up a special fire pump "Architectural Design Code of Fire Prevention" (hereinafter referred to as "Construction Regulations") Article 8.6.3 states: "set temporary high-pressure water supply system should be set fire water tank or pressure Jug, water tower. " According to this provision, the establishment of temporary high-pressure fire water supply systems should be set fire water tank. This type of building is mostly a multi-storey building of 4,5 storeys, while the pressure of the municipal pipe network is generally 20-30 meters water column. In order to meet the needs of the most unfavorable point hydrant required substantial water column, such buildings should also be set fire pump. However, the purpose of providing indoor fire hydrant system in multi-storey buildings is only for fighting the initial fires. A large amount of rescue work also depends on the urban fire brigade. Therefore, it is inevitable to set fire-fighting pumps wastefully. For this type of building, I do not know whether it is possible to learn from the high-rise building in the fire water tank outlet pipe set supercharging facilities practice, the fire water tank outlet pipe set through the fire hydrant box button or by fire water tank outlet indicator Start booster pump to meet the need to enrich the water column. This approach, booster pump set in the roof, is light-load start, start fast, the initial fire fighting should be beneficial. In addition, municipal pipe network to meet the indoor and outdoor fire water on the premise, I do not know whether to consider depending on the building for different purposes to determine whether to set the fire pump. That is, in the factory buildings and large public buildings, the establishment of a fire pump to promote self-help capacity to some extent, while in the general residential area, it allows no fire pump, the fire pump using water pump adapter in the outdoor water After all, even if a fire pump is installed in a residential building, residents may not be able to use it properly.

Fire pump performance and test requirements Fire pump and life pump and pump production performance should have higher requirements, but the current norms of our fire pump performance and test requirements did not make more detailed provisions, resulting in There is no evidence of fire pump in use, there have been many problems. US NFPA20 fire pump performance requirements are: fire pump maximum flow should be 150% of the design value, the lift is not less than 65% of the selected working point lift, shut down the pump lift is not greater than 140% of the selected work point lift, , The regulator pump flow is 1-2L / S, lift for the fire pump head 1.1-1.2 times. At the same time the provisions of the fire pump outlet pipe should be set to measure the flow meter, the flow meter should be able to test the pump selected flow of 175%, the fire pump on the outlet pipe should be set diameter greater than 89mm pressure gauge. Suggest that the relevant departments of the reference to the United States standards for fire pump design, selection of more targeted, more specific requirements, so that the fire pump selection, testing is well documented.

Third, the laying of the pump line found in many design drawings: fire pump for power distribution lines, control lines and more wear PVC pipe to protect, and from the ceiling within the alignment. I think this alignment method is defective. Although the "Construction Regulations" only require that the power distribution lines of fire-fighting electrical equipment be worn with metal pipes and no metal pipe protection is required when concealed, the "Code for Design of Electrical Buildings in Civil Buildings" (hereinafter referred to as "the Civil Regulation") 24.8. 5 requirements: fire linkage control, automatic fire control and other lines should be used flame retardant cable to wear the pipe in the non-burning body structure layer, the protective layer thickness of not less than 3cm, when it must be clear, should be on the metal pipe Take fire precautions. Article 8.2.2 of "Code for Design of Automatic Fire Alarm System" (hereinafter referred to as "automatic alarm specification") also makes corresponding provisions in this regard. We know that fire pumps still have a role to play for some time after a fire broke out, to complete the construction fire fighting efforts. Therefore, in this period of time, still to ensure the safety of the pump line. For the distribution room and the electric shaft distance farther, fire power equipment capacity larger, the line can not be concealed, you can take effective fire prevention measures laid in the ceiling. In this case should avoid the use of fire-resistant slot box, because the ceiling is also fire-prone lots, the laying of the line in the ceiling fire and unsafe, and the tank can only prevent the external combustion of the line damage, can not prevent the line box Fire caused by its own fault. Fire pumps and other important fire-fighting equipment recommended fire-resistant cable power supply to ensure that in case of fire can be affected within a certain period of time to continue to work.

Fourth, fire pumps should be set over-load protection Fire pump is an important fire-fighting equipment, fire fighting plays an extremely important role. According to our habitual thinking, overload protection should be provided for all important equipment. However, Articles 8.6.3.5 and 10.2.2.4 (3) of the "Regulations" stipulate: "For a power distribution line that causes a more serious loss than an overload due to a sudden power failure, it should not be installed Load protection electrical appliances (such as fire pumps, power supply lines), but should be installed overloaded alarm appliances. As such, fire pumps should not be installed overload protection cut off device. This is mainly due to the fact that when a fire breaks out, the need for fire-fighting water should be fully ensured because of the negligible loss of equipment from the loss of fire due to the possible damage caused by the pump overload. However, even in the actual construction of some standard construction atlas, including the current teaching materials in colleges and universities described in the fire pump electrical diagram, the fire pump circuit is still equipped with overload protection cut off electrical appliances, such as "Building Electrical Installation Engineering Atlas JD13- 318 page "high-rise building fire protection system full voltage start fire pump control device (b)". This obviously does not meet the regulatory requirements.

Fifth, fire pump control (1) control voltage. Article 24.6.2.1 of the "Civil Regulations" stipulates that the control circuit for starting the fire pump in the fire hydrant box and for starting the pump light shall adopt the safe voltage below 50V. Section 24.9.11 states: The DC operating power supply voltage of the fire linkage should be 24V. This is mainly to prevent the use of fire hydrants, water overflow fire hydrant boxes and water, water guns and electric fire and firefighters (such accidents are heard when the accident). However, in the actual construction and some references in the operation of hydrant button power voltage is still received AC 220V, as mentioned earlier "Atlas" on the same page to make such a mistake. (2) start the control. Fire hydrant pump has three places to start control. â‘  According to "Build Regulations" and "Fire Code for High-rise Civil Building Design" requirements, start directly in the indoor fire hydrant box. â‘¡ According to "automatic alarm specification" requirements, at the fire control room at the control. â‘¢ pump room near the fire hydrant pump control. This should be the correct treatment of the following two issues: First, we should correctly determine the fire control room, fire hydrant button and fire pump control priority issues. In general, long-distance fire control room should be dominated. However, due to the absence of a clear guideline for long-distance operation by relevant departments at present, there are many practices in engineering practice, and the rationality and operability are inevitably mixed. Some simply start and stop the pump button and / or connected to the secondary loop manually start and stop the pump button, and some simply remove the thermal relay, most of them are set in the pump room control cabinet manual / automatic transfer switch, under normal circumstances Put in automatic position. We think all these methods have some defects. Comrade Song Gaofei "On the design of fire pump remote operation," a paper proposed long-distance operation relay contacts over the switch part of the direct contact with the fire pump main contactor coil loop to achieve the direct start fire pump. We think the idea is good, not only solve the problem of direct start, but also facilitate the unified control of the control room, but also to meet the needs of the pump room control cabinet in any state can start fire pump remotely. The second is to determine the fire pump to take what way to start. As soon as possible to put fire fighting equipment into operation to reduce fire loss, taking into account the majority of non-fire load in the fire has been cut off, fire pumps should give priority to the use of full pressure direct start mode. (3) fault control. According to "automatic alarm specification" requirements of Article 4.2.1, fire control room should be able to display the fire equipment failure status. Due to technical problems, the simple failure signal such as power failure can be displayed on the fire control signal, and other fault signals such as fire pump overload fault signal are not specified in the "Automatic Alarm Specification" and "Civil Regulations" Often avoid this point, affecting the control room on the correct detection of equipment failure. (4) Manual alarm button instead of the hydrant button to start the pump. Replace the fire hydrant button with the newspaper at the fire hydrant Department Kai pump is more popular in engineering practice, the project more with double contact button, a contact for hand newspaper use, the alarm signal is sent to the fire alarm controller, the other contact to start Pump button, the pump signal to the control room by the double switch box pump. However, according to Article 8.6.2 (9) of the "Construction Rules", Article 7.4.6.7 of the "High Rules": Each fire hydrant shall be provided with a button to directly start the fire pump. The hand newspaper button pump is the fire signal feedback to the alarm linkage controller, confirmed by the controller to start the fire pump, fire pump is not directly activated. Moreover, this alternative to automatic alarm system put forward higher requirements. At present, due to the problems of high false alarm rate and operating cost of automatic alarm system, some automatic alarm systems of buildings are often not operated with sickness and are hard to play their due role. Therefore, we do not think it is necessary to advocate the use of hand newspaper instead of the hydrant button to start the fire pump.

Sixth, the regular maintenance of fire pumps Despite the norms, rules and regulations clearly require fire-fighting facilities, equipment should be regularly maintained, but the current fire pump can not do regular test run, the protracted cause of the pump stuck, rust died, as a fire can not Play its due role On October 25, Guangzhou Daily reported on the topic "why 500,000 yuan of fire-fighting facilities dripped" because it disclosed that the fire-fighting facilities inside the Yidd Road Integrated Market in Yuexiu District were not maintained and could not operate normally during the fire and caused huge losses . Therefore, we recommend that the code require the use of programmable logic controller (PLC) in the fire pump control of the pump set to achieve the fire pump in the standby test run regularly to save the fire started automatically in order to effectively eliminate the fire pump key moments Can not use the situation. The above opinion is only our personal superficial opinion, please correct me wrong.

Hydrophilic

Hydrophilic,Hydrophilic Silica With Dds Treatment,Hydrophobic Silica In Coatings,Silicon Dioxide With Hydrophobic Groups

Henan Minmetals East New Materials CO. LTD. , https://www.eastinsulations.com

June 10, 2024