Heating Ventilation Air Conditioning
Heating Ventilation Air Conditioning projects include: seven sub -branch projects such as exhaust system, smoke anti -exhaust system, dustproof system, air -conditioning system, purifying air system, refrigeration equipment system, and air -conditioning water system.
The focus is: the composition of ventilation and air conditioning system; engineering construction content, procedures and technical points; the level of cleanliness and the technical requirements of clean air -conditioning engineering construction.
Master the construction procedures for ventilation and air -conditioning engineering:
1. The composition and category of ventilation and air conditioning system
(1) Composition of ventilation system
Including: intake processing equipment, such as air filtering equipment, hot and wet treatment equipment and air purification equipment, etc.;
Permanent fir or exhaust fan;
Wind duct system, such as air ducts, airports, exhaust ports, exhaust hoods, etc.;
Exhaust treatment equipment, such as dust collectors, harmful gas purification equipment, hats, etc.
2. The category of the ventilation system is:
(2) Composition of the air conditioning system
——It air treatment equipment, heat source and cold source, air -conditioning wind system, water system, control, adjustment device
(1) Air treatment equipment: air heating or cooling equipment, air humidification or humidifying equipment and air purification equipment, etc.; Its role is to deal with air supply air to a certain state.
(2) heat source and cold source: commonly used heat sources include boilers with hot water or steam, electric heater, etc.
(3) Air conditioning wind system: consisting of a fan and a duct system.
(4) Water system: Including the cooling water system that transports frozen water (or hot water) from the refrigeration system (or thermal source) to the air treatment equipment and the cooling water system of the refrigeration equipment, consisting of the water pump and the water pipe system.
(5) Control and adjustment device: The role of the device is to regulate the cooling, calories, air volume, etc. of the air -conditioning system, so that the work of the air -conditioning system can adapt to changes in the air conditioning conditions, thereby controlling the indoor air condition within the scope of the required range.
2. The main content and construction procedures of ventilation and air -conditioning engineering construction
——The construction content of ventilation and air -conditioning engineering:
Mainly include: installation of ventilation and air treatment equipment, prefabrication and installation of other pipeline systems, installation, system debugging and engineering trial operation of other pipeline systems.
——The construction procedures for ventilation and air -conditioning engineering:
Construction preparation — → air duct and component processing — → air duct and component intermediate acceptance — → air duct system installation — → blasting system strict test — → air -conditioning equipment and air -conditioning water system installation — → air duct system test and adjustment — → Air conditioning system debugging → Completion and acceptance of the comprehensive performance of cold air -conditioning system.
3. The construction technology points of the air duct system
The ventilation and air -conditioning engineering air duct system can be divided into:
Low -voltage system (P≤500Pa), mid -voltage system (500 <P≤L500Pa) and high -voltage system (P> L500Pa).
(1) General requirements for the production of air duct system
1. The production and installation of the air duct system shall be carried out in accordance with the approved construction drawings, contracts, or engineering records, related construction plans and standard specifications.
2. The plate materials, profiles, and other finished materials used in the air pipes shall meet the requirements and design requirements of relevant national product standards, and have corresponding factory inspection certification documents.
Construction technology note:
A -Non -metallic composite air duct board must be a non -combustible material. Internal thermal inside the air tube with insulation performance should not be lower than the difficult BL Class; Grade material;
C — The fire resistance level of a smoke -proof system air duct should comply with the design regulations. The body, framework, connecting fixed materials and sealing cushions, valve components, insulation materials, and flexible short pipes and mufflers must be non -burning. Material.
If there is no requirements for the thickness of the smoke duct board, the thick -pressure system duct board can be selected. Key point:
The appearance quality requirements of ventilation and empty withered engineering pipeline pipelines
The splicing seam of the plate should be reached:
——The stitching is straight, flat, strict and firm, and does not expose the insulation layer;
——The intensity requirements for the structural connection;
——The air duct for its working pressure level, plate thickness, air duct length and section size, and take the corresponding reinforcement measures; ——Cian -shaped internal diagonal lines and internal arc elbows should be conducted to reduce local resistance of the air duct And noise.
(2) The installation points of the air duct system
Construction technology note:
Cutting branches, suspension, bracket steels and its snail holes should be processed by mechanical processing, and electrical welding shall be used; branches and hanging racks should not be set at air outlets, valves, inspection doors and self -control devices.
Construction technology note:
The air or smoke that is higher than 70°C in the anti -smoke discharge system or the transport temperature is higher than 70°C.
Sending gases containing corrosive media should be used for acid -resistant rubber plates or soft polyethyl chloride plates.
The point is: air duct installation position program
——Pougly upper layer, then lower layers, first tube tube and then support, first pipe tube, and horizontal tube, you should pay attention when you are in place.
Construction technology note:
When the air duct through the fire -fire explosion -proof floor or wall, the thickness of the steel plate shall be set up with a embedded pipe or protective sleeve with a thickness of not less than 1.6mm. The non -combustible flexible material should be blocked between the air duct and the protective sleeve.
2. After the air duct system is installed, a strict test must be performed, and the main test must be performed:
——The bite seam, rivet pores, flange edges of the air ducts, and the connection between the air duct sections are tight!
The tight inspection of the air duct system, under the premise that the processing process is guaranteed, the duct system with different work pressure adopts different methods:
——The low -voltage duct system can be detected by light leakage method;
——The medium pressure system shall be performed after passing the light leakage method to pass the air leakage test;
——The high -voltage system conducts air leakage tests.
(3) The requirements for debugging and air -conditioning engineering debugging
1. Process process of ventilation and air -conditioning engineering debugging
Organize on -site debugging teams
— → debug preparation and on -site survey
—→ various inspections before system debugging
— → System air volume and water volume measurement and adjustment
— → ventilation and air -conditioning system Equipment Single -machine trial operation and adjustment
— →building and fire self -control system related equipment related equipment Inspection
— → air conditioning and ventilation single equipment self -control debugging
— → air conditioning and ventilation, smoke anti -exhaust system self -control linkage
— → The system has no production load combined trial operation and debugging
— → data finishing and transfer.
2. The main content of system debugging
Wind volume measurement and adjustment, stand -alone trial operation, and no production load joint trial operation and debugging.
The normal joint trial operation of the air -conditioning system with a cold (thermal) source shall make a decision according to the completion season and design conditions. In summer, you can only use the cold source test to run, and only the heat source test movement during the winter.
The construction unit can enter the completion acceptance after the system has no production load joint trial operation and debugging. 3. The comprehensive efficiency test and adjustment of the production load of ventilation and air -conditioning engineering belt shall be carried out under the conditions of production trial operation. The construction unit shall be responsible and the design and construction unit will cooperate.
The comprehensive performance test measurement and adjustment project shall be determined by the construction unit according to the engineering nature and production process requirements.
Understand the construction technology of clean air conditioning project
In addition to meeting the temperature, humidity, indoor positive pressure, and noise standards required by the cleaning room, it is more important to make the air cleaning the cleanliness of indoor air after filtering the medium -efficiency and high -efficiency filter.
1. Cleanliness level
The standard of air purification is commonly used to measure the level of air cleanliness. The air cleanliness mainly controls the minimum control particles and the number of particles in the air, that is, the maximum number of particles per cubic meter of volume to determine. The current specifications specify the nine cleanliness levels of NL to N9.
Remember:
The standard for air purification is measured by the level of air cleanliness;
The current specifications specify the nine cleanliness levels of NL to N9.
Second, the construction points of clean air conditioning system
(1) Technical points for the production of air ducts
Key point:
——The technical difference between the air ducts of the clean air conditioning system and the air duct construction of the general ventilation air -conditioning system:
The difference between the air ducts of the clean air -conditioning system and the air duct of the general ventilation air -conditioning system are higher requirements for the degree of cleaning and strictness of the surface of the duct.
1. The stiffness and strictness of the air -conditioning system to make the air -conditioning system are carried out in accordance with the duct requirements of high voltage and mid -pressure system, of which:
Cleanliner NL level to N5 level, according to the air duct production requirements of the high -pressure system;
N6 -level to N9 level -based air duct production requirements.
2. The production of clean air -conditioning system ducts and components should be carried out in a relatively closed and clean environment. The ground should be paved with rubber plates or other protective materials.
3.(1) Machined galvanized steel plate duct should avoid damaging the galvanized layer. If it is damaged, anticorrosion should be treated.
The air duct must not have horizontal seams, and minimize the vertical stitching seams as much as possible;
When the side length of the rectangular duct is not greater than 800mm, there must be no vertical seams;
All bits, edges, and rivets of the air duct must be applied to sealing
(2) Technical points for the installation of the air duct system
The air duct installation of the clean air -conditioning system also has higher requirements for its cleanliness and strictness.
Remember the environmental requirements of construction:
Before the installation of the air duct, the construction site was completely cleaned, so as to achieve dust -based operations, and to establish effective dust prevention measures.
After cleaning the packaging and sealed ducts and parts, it must not be removed before installation; if the installation is paused, the port should be seal again.
The air duct connection must be tightly, the flanges should be used for elastic materials that are not produced and not easy to aging. It is strictly forbidden to brush the coatings on the surface of the pad.
