Does the fire smoke exhaust duct need fire insulation and insulation?

The fire smoke exhaust duct generally does not need to be insulated, and the fire air duct requires non-combustible materials. If non-combustible materials are used, then there is no need for fire protection.

All kinds of frying, stir-frying, steaming, boiling, frying, baking and other equipment in the kitchen constantly produce various high-temperature, humid and polluting gases in the process of processing food. Accumulate to a certain extent、The kitchen will not be suitable for further work。 Therefore, it is necessary to use a fan to exhaust the pollutant gas out of the kitchen through the smoke exhaust pipe.

Kitchen fan is an indispensable key equipment in the kitchen, it is recommended not to install it in the ceiling, but to install it in the machine room, roof or exterior wall and other places that are easy to maintain. Kitchen fans work in high temperature, humidity and oil smoke for a long time. Regular maintenance is indispensable.

The air duct of the fire smoke exhaust fan generally does not need to be insulated, but I don't know whether there are local standards in the cold areas of the north. However, there are requirements for fire air ducts, which are not materials. If you are using materials that are not used, then fire protection is not a concern.

It shouldn't be necessary, why do you need to keep warm? In fact, the temperature of the smoke exhaust of the real fire is very high, and the insulation material will be melted or baked into a shriveled type on it.

It is best to be fireproof and insulated, otherwise there is a fire hazard when emitting high-temperature smoke!

Technical Standard for Building Smoke Prevention and Smoke Exhaust System [with Explanation of Provisions] GB 51251-2017

The smoke exhaust duct needs to be insulated - the smoke exhaust pipe should be insulated with non-combustible materials.

4 4 7 The mechanical smoke exhaust system should use pipe smoke exhaust, and civil air ducts should not be used. The smoke exhaust duct should be made of non-combustible materials and the inner wall should be smooth. When the inner wall of the smoke exhaust pipe is metal, the design wind speed of the pipe should not be greater than 20m s; When the inner wall of the smoke exhaust pipe is non-metallic, the design wind speed of the pipeline should not be greater than 15m s; The thickness of the smoke exhaust pipe shall be implemented in accordance with the relevant provisions of the current national standard "Code for Acceptance of Construction Quality of Ventilation and Air Conditioning Engineering" GB 50243.

4 4 8 The setting and fire resistance limit of the smoke exhaust pipe shall comply with the following provisions:

1. The smoke exhaust pipe and its connecting parts should be able to ensure its structural integrity for 30min continuously at 280 hours.

2. The smoke exhaust pipe set vertically should be arranged in an independent pipe well, and the fire resistance limit of the smoke exhaust pipe should not be less than 0 50h.

3. The smoke exhaust pipe set horizontally should be set in the ceiling, and its fire resistance limit should not be less than 0 socks for 50h; When there is a real difficulty, it can be directly installed indoors, but the fire resistance limit of the pipeline should not be less than 1 00h.

4. Smoke exhaust pipes installed in the ceiling of the walkway part, and through the fire partition.

The fire resistance limit of the smoke exhaust pipe should not be less than 1 00h, but the fire resistance limit of the smoke exhaust pipe of the equipment room and garage can not be less than 0 50h.

4 4 9 When there are combustibles in the ceiling, the smoke exhaust pipe in the ceiling should be insulated with non-combustible materials, and should be kept at a distance of not less than 150mm from the combustibles.

Summary. Dear, hello, I am glad to answer for you the need for smoke exhaust duct fire resistance for 1 hour, what material to use?

Answer: The fire resistance limit of hot-dip galvanized iron duct is one hour, and it will not collapse after 1 hour of combustion.

There is no fire resistance limit for galvanized steel alone, because according to the provisions of GB50016-2014 (2018 edition), the fire resistance limit includes load-bearing capacity, integrity and thermal insulation. For the galvanized steel sheet used to make the air duct, there are requirements for integrity and thermal insulation, and it is obvious that galvanized steel sheet alone cannot meet the thermal insulation.

Therefore, the galvanized steel plate with fire resistance limit needs to be equipped with a thermal insulation layer, which can be a fireproof coating (divided into thick coating type and thin coating type) or fireproof packaging, the cost of fireproof coating is expensive, and the effectiveness of its heat insulation is not as good as fireproof packaging, and when the fire resistance limit is greater than, thin-coated fireproof coating should not be selected.

What material should be used to prevent smoke exhaust air duct for fire resistance for 1 hour?

Dear, hello, I am glad to answer for you the need for smoke exhaust duct fire resistance for 1 hour, what material to use? Answer: The fire resistance limit of hot-dip galvanized iron duct is one hour, and it will not collapse after 1 hour of combustion.

There is no fire resistance limit for galvanized steel alone, because according to the provisions of GB50016-2014 (2018 edition), the fire resistance limit includes load-bearing capacity, integrity and thermal insulation. For the galvanized steel sheet used to make the air duct, there are requirements for integrity and thermal insulation, and it is obvious that galvanized steel sheet alone cannot meet the thermal insulation. Therefore, the galvanized steel plate with fire resistance limit needs to be equipped with a thermal insulation layer, which can be a fireproof coating (divided into thick coating type and thin coating type) or fireproof packaging, the cost of fireproof coating is expensive, and the effectiveness of its heat insulation is not as good as fireproof packaging, and when the fire resistance limit is greater than, thin-coated fireproof coating should not be selected. Thank you.

Fire smoke exhaust ventilation insulation specifications require how thick the insulation is! Hello, I am glad to answer for you<> 1. The distance between the outer surface of the exhaust air duct and the combustible components such as wood should not be less than 15 years old, or the outer surface of the exhaust flue is covered with insulation materials with a thickness of not less than 10. 2. When the smoke exhaust trap passes through the smoke retaining wall, the gap between the air duct and the smoke retaining wall should be tightly filled with non-combustible materials such as cement mortar.

3. The connection between the exhaust air duct and the smoke exhaust fan should be connected by flange or soft connection without combustion. 4. Metal exhaust flue that needs to be insulated. Non-combustible insulation materials must be used, such as mineral wool, glass wool, rock wool, aluminum silicate and other materials.

5. The material of the flue gas outlet should be made of materials with good fire resistance; The location of the outlet should be determined according to the conditions of the building, and the area with a burning hazard must be avoided, and I hope that mine can help you <>

Do you have any other questions?

This need, according to the requirements of the code, there may be high temperature in the fire smoke exhaust pipe, so it is necessary to adopt protective measures when the pipeline and other heat conduction spacing cannot be met, and this needs to be considered if the spacing with other pipes can not meet the requirements of 200mm.

Smoke exhaust pipes do not need to be insulated. The purpose of smoke exhaust pipe exhaust is to discharge indoor smoke and dust to the outside through the exhaust machinery, and ventilation is to force the indoor and outdoor air to circulate through machinery, and the ventilation direction and location are different;

The air quality in circulation is different, so you can't use the same pipe, otherwise, it will backfire if you accidentally pass the smoke and dust into the room during ventilation. Finally, the installation standards of smoke exhaust pipes and exhaust pipes are different, and smoke exhaust fire dampers should be installed in the smoke exhaust pipe system, while ordinary exhaust pipes do not need to be installed.

The requirements for the insulation layer in the fire smoke exhaust ventilation insulation specification are that it needs to have an appropriate thickness to prevent condensation and reduce heat loss, and also consider the fire performance of the insulation material. Therefore, the specific thickness of the insulation should be determined according to the actual situation of the building, the ambient temperature, the use requirements and the temperature difference between the inside and outside of the building.

In general, the requirement in the fire exhaust ventilation insulation specification is that the minimum insulation thickness is not less than 50mm, and according to different insulation materials and use requirements, it may be necessary to increase the insulation thickness. For example, when silicate insulation materials and polystyrene insulation materials are used, it is generally necessary to increase the thickness of the insulation layer in accordance with the requirements of the specification.

In short, in the design of fire smoke exhaust ventilation and thermal insulation, it is necessary to combine the actual situation and specific requirements of the building, and reasonably determine the thickness of the insulation material according to the code requirements and technical standards, so as to ensure that the heat loss inside the building is reduced, and at the same time meet the safety requirements of the building. In order to ensure the accuracy of the design, calculations and guidance should be carried out by professional engineers.

How thick should the specifications of fire smoke exhaust ventilation and thermal insulation be, which is determined according to the requirements of the drawings, the specifications usually used are special glass wool small bright finger time and 1 hour fire resistance limit, the materials and fire resistance limits used in each part of Senjian Jing are different, silicate fireproof wrapping has 1-2 hours Fire resistance limit This caution, fiber reinforced fireproof board has 2-3 hours fire resistance limit.

There are 2 ways to achieve fire resistance for 1 hour:

The first type: metal air duct fire-resistant coating system

The refractory coating system of metal air duct is filled with 50mm rock wool on the outer surface of the original metal air duct and covered with 9mm magnesium crystal air duct plate. After coating, the fire resistance integrity and heat insulation of the original metal air duct are increased to 3 hours.

The second type: magnesium crystal metal composite refractory air ductMetal composite refractory air duct is a set of metal layer, heat insulation layer, reinforcing layer as one of the refractory air duct, in order to meet the requirements of the standard fire resistance limit at the same time, metal composite refractory air duct to achieve integrated installation, process reduction, convenient installation, greatly reduce the construction cost.

It's good for you to use the refractory air duct directly, and another way is to make a package after the air duct is done.

There are the following ducts that need to be insulated:

1. The air duct medium is the gas after cold and heat treatment, such as air conditioning air supply pipe and air conditioning fresh air duct.

2. The air duct entering the air-conditioned area needs to be insulated. For example, the exhaust smoke duct (high-temperature resistant insulation material) entering the air-conditioning area

3. According to the fire protection requirements, the fire smoke exhaust air duct in the ceiling must be insulated with non-combustible materials.

If you are not clear, you can consult the heating and ventilation design code and the national civil building technical measures - HVAC - power.

Answer: The air duct of the fire smoke exhaust fan generally does not need to be insulated, but I don't know whether there are local standards in the cold areas of the north. However, there are requirements for fire air ducts, which are non-combustible materials. If you're using non-combustible materials, then fire protection doesn't have to be a concern.

The fire smoke exhaust pipe has high requirements for the selection of air ducts, considering that it should be flame retardant, followed by fire resistance. There are two commonly used categories:1

High-temperature ventilation pipe: national certification flame retardant performance, the temperature of high-temperature ventilation pipe can reach -70 degrees to 350 degrees, the main structure is a special flame retardant insulation fiber in the middle, the inside and outside are covered with high-temperature glue, the middle contains steel wire, which can be supported and telescopic, and the appearance is reinforced with white fiber threads. Generally, the application of high-temperature ventilation pipes in aviation equipment and military equipment, in the industry with strict regulations, the performance of high-temperature ventilation pipes can basically meet the use, and it is more general.

2.High-temperature rubber ventilation pipe: The high-temperature rubber ventilation pipe is light in texture, excellent in extraction and conveying, and the pipe wall will not be concave when bending, nor will there be any deformation.

Therefore, in the fire smoke exhaust system, the high-temperature rubber ventilation pipe is a good choice.

Hope it helps, dear