On the fire damper, exhaust valve engineering quality

Abstract: This paper describes the main purpose of fire damper and exhaust valve, and its important role in ventilation, air conditioning and smoke control systems. It also expounds the logical relationship between the quality requirements of engineering application and the fire linkage requirements of the relevant national norms, As well as the project quality problems discovered by the author in the daily fire inspection, engineering inspection and acceptance work; and pointed out the importance of installation and construction quality, linkage debugging and maintenance management. Key words: fire damper, exhaust valve, smoke control, engineering quality 1, fire damper, the main purpose of the exhaust valve High-rise and other types of modern buildings are equipped with ventilation, air conditioning and smoke exhaust system, in the event of a fire, these systems will be the pipeline of flames, smoke spread channel. In order to prevent the spread of the fire through the duct expansion, in the "Building Code for Fire Protection" GBJ16-87 and "Code for Fire Protection Design of High-rise Civil Building" GB50045-95 are clearly set the fire damper, exhaust valve set requirements. Fire damper used in ventilation, air-conditioning system to send and return air lines, usually open state, when a fire occurs, the pipeline gas temperature reaches 70 ℃ when the self-closing, and within a certain period of time to meet the fire resistance and fire resistance Integrity requirements, smoke from the fire effect. Exhaust valve is used in the smoke exhaust system pipe or exhaust fan suction inlet, usually was closed, when a fire occurs, the fire alarm signal manually or automatically open the valve, according to the system function with smoke, when the pipe smoke Gas temperature reaches 280 ℃ automatically shut down and can meet the fire resistance stability and fire integrity requirements within a certain period of time, smoke from the fire retardant effect. 2, fire damper, exhaust valve in the ventilation, air conditioning and smoke control system, the important role Fire damper, including gravity fire damper, fire control valve, fire vent, pneumatic fire damper, smoke damper, electronic smoke control fire Valves and other products; exhaust valve, including smoke fire damper, plate exhaust port (ceiling), shaft exhaust port and other products. Fire damper, smoke exhaust valve ventilation, air conditioning and smoke exhaust system is an important component in the system to play an important role in the following three aspects: 2.1, fire smoke blocking effect In the air supply system, the fan sends the wind Must be assigned to the branch pipe through the main pipe; in the exhaust system, the flue gas from the branch pipe to the main pipe, into the exhaust fan exhaust. When a fire occurs in the building, in the ventilation and air-conditioning system, in order to prevent the spread of the fire through the air supply system, when the temperature of the air in the air supply system reaches 70 ° C, the fuse on the fireproof valve mechanism operates and the valve rapidly closes, Cut off the flue gas and fire spread along the duct path. Similarly, in a smoke exhaust system, in the event of a fire, the smoke exhaust valve is opened to exhaust smoke. In order to cut off the flow of high-temperature smoke in the smoke exhaust pipe and prevent the spread of fire to another fire prevention zone, when the temperature of the exhaust gas reaches 280 ℃, the smoke fire damper, fume exhaust port on the move, the valve must be automatically closed to prevent smoke. Thus, fire damper, exhaust valve to do the pass, the broken off the smoke blocking effect. 2.2, the regulatory role in the ventilation, air conditioning system piping design, although the calculation, but the actual operation of the project if there is a change, you need to pass through the fire damper valve on the various parts of the system to regulate air flow, the system debugging, will Valve opening fixed, rational distribution, to meet the design requirements. 2.3, to start the role of no-load ventilation and air conditioning and smoke exhaust system in all centrifugal fans and fire smoke exhaust axial fan, during installation and debugging, for safety reasons, the motor starting current minimum, usually no-load start, temporary through the valve Cut off the pipeline to achieve. 3, the quality requirements of engineering applications 3.1, product quality requirements At present, fire prevention, smoke exhaust a lot of product manufacturers, our fire supervision, audit department and design department should be strictly checked, so that Party A choose "three certificates" complete and qualified Products, that is, to have the manufacturer's factory certification, public security fire department product sales permit, the National Fire Building Materials Quality Supervision and Inspection Center of the product inspection report. From the national inspection report and product technical parameters can reflect the product performance and quality, based on the national standard "fire valve test method" GB15930-1995 and "smoke fire valve test method" GB15931-1995. The product quality requirements embodied in five aspects: 3.1.1, temperature sensor action performance test Fire damper, exhaust valve temperature sensing element, respectively, by the constant temperature water bath, oil bath temperature, through the action and action test, Check if it can be accurately shut down at the required temperature. 3.1.2. Closure reliability test Closure operation 250 times on the test bench, the test piece should be able to be closed from the open position flexible and reliable, the parts should be no significant wear and tear, deformation and damage affecting its sealing performance. In order to test the reliability of closure. 3.1.3 Salt Spray Test Spray salt spray test specimens in the salt spray box, the specimen should be able to reliably close the open position, in order to test the valve in the actual project of the anti-corrosion ability. 3.1.4, air leakage test Before and after the body under the provisions of the pressure conditions, the sample unit area of ​​air leakage is not greater than 700Nm3 / (h · m2), in order to test the closed valve performance after the closure. 3.1.5 Fire resistance test Fire resistance test, according to the closing time within a specified time and unit area of ​​air leakage two indicators to determine the valve fire resistance. In addition, the technical parameters of the product required its resistance to fire 3h. 3.2 Installation Quality Requirements In daily fire inspection and project acceptance work, I found that due to the installation of construction quality problems caused by fire exhaust valve is not open or malfunctioning, exhaust valve, exhaust port, fire damper, fire vent reset difficult . This should arouse the attention of the construction side, pay attention to the following installation requirements. 3.2.1, fire damper, exhaust valve should be strictly according to map construction, a separate hanger to prevent the duct deformation at high temperatures, affecting the valve function. 3.2.2, When the valve is installed on the suspended ceiling or in the air duct, a maintenance access hole shall be provided on the ceiling or on the air duct wall. The general size of the access hole shall not be less than 450 × 450mm. When the conditions are limited, the access hole for the suspended ceiling may also be Reduce to 300 × 300mm. 3.2.3, the fire damper and the firewall (or floor) between the duct should be used δ ≥ 1.5mm steel production, the best wind pipe and then the outer refractory insulation or non-flammable material protection to ensure that the firewall Fire resistance. 3.2.4, in the valve operation machinery side should have a net space of 350mm, in order to facilitate maintenance. 4, fire prevention, exhaust valve in the project there are some problems I am in the routine fire inspection, engineering inspection and acceptance work, found that fire, exhaust valve there are some problems the following points for peer reference. 4.1, fire control room to send, return duct in its wall without fire damper. During the course of the construction audit, it was found that some engineering drawings on the control room to send and return duct in its wall without fire damper, which is inconsistent with the "fire alarm system design specification" GB50116-98 in 6.2.2. The purpose of fortification fire valve is to ensure the fire control room fire safety. 4.2, fire control equipment on the smoke, smoke control facilities, display imperfections According to the specification GB50116-98 in the provisions of Article 6.3.9: After the fire alarm confirmation, you must stop the relevant parts of the air conditioning, turn off the electric fire Valve, and receive the feedback signal; at the same time start the relevant parts of the smoke and exhaust fan, exhaust valve, etc., and receive its feedback signal. Some engineering linkage control can not be partitioned control exhaust valve, exhaust port, and some can not receive the feedback signal, can not reflect the valve opening and closing conditions. 4.3, pipe network gas fire extinguishing system without pneumatic fire damper. Section 6.3.4.3 of GB50116-98 requires: "During the delay period, the fire doors and windows shall be automatically closed and the ventilation and air-conditioning system shall be stopped and the fire damper of the relevant site shall be closed." This requires that in the gas fire-extinguishing system of the pipe network, pneumatic Fire damper, and fire control equipment linkage. In individual projects do not have this feature. 4.4, the supply air and smoke exhaust duct without remote control Some buildings in the basement, the use of air and exhaust parking combination of air duct, we found that the blower and exhaust valve in front of the globe valve can only be manual, can not achieve control Room remote control, usually, blower work, the front of the globe valve is open, in case of fire, the need to go to the scene to close the fan before the stop valve, it is not practical, a direct impact on the exhaust system. Therefore, it is recommended to increase the remote control valve function. 5, the system linkage debugging and maintenance management. Fire damper, exhaust valve in the actual project is not an independent fire retardant products, but in the fire linkage control system has its unique linkage logic. Therefore, in order to ensure its function in the fire protection system, before the system acceptance, according to the linkage requirements, it must be fully debugged so that ventilation, air conditioning and smoke control systems meet the regulatory requirements. After inspection, someone should carry out planned routine maintenance and management to ensure that the valve body is in a normal condition and perform its function in the role of smoke and fire retardant.

Posted on