Views: 0 Author: Site Editor Publish Time: 2022-10-28 Origin: Site
Following the news updated on Oct. 24, we continue to introduce the ventilation and air conditioning duct installation method for you:
1. The installation of various air duct components and operating mechanisms should be able to ensure their normal use functions and be easy to operate. The installation direction of the check air valve and automatic exhaust valve should be correct. The installation direction and position of the fire damper should be correct. When the diameter or length of the fire damper is greater than or equal to 630mm, independent supports and hangers should be provided. The fire dampers on both sides of the partition wall of the fire compartment should not be more than 200mm away from the wall surface. The position of the exhaust valve (port) and the manual control device (including the embedded casing) shall meet the design requirements. The embedded casing shall not have dead bends and sags. The regulating valve of the suction pipe section of the dust removal system should be installed on the vertical pipe section.
2. When the air duct passes through the fire-proof and anti-riot wall or floor that needs to be closed, a pre-buried pipe or protective casing should be provided, and the thickness of the steel plate should not be less than 1.6mm. Between the air duct and the protective casing, a non-combustible and non-hazardous flexible material should be used to block it.
3. When the air duct passes through the settlement joint, a 100mm thick asbestos rope should be placed between the duct and the wall bushing.
4. Duct detection
1). After the installation of the air duct system, the tightness inspection should be carried out according to the system category, and the air leakage should meet the design and the following requirements:
(1) The strength of the air duct should be able to meet the requirement of no cracking at the joint under 1.5 times the working pressure.
(2) The allowable air leakage volume of low-pressure and medium-pressure circular metal air ducts, composite air ducts and non-metallic air ducts in the form of non-flanges shall be 50% of the specified value of rectangular air ducts.
(3) The allowable air leakage volume of the soil air duct should not be greater than 1.5 times the specified value of the rectangular low-pressure system air duct.
(4) The smoke exhaust, dust removal, and low temperature air supply system shall comply with the regulations on the air duct of the medium-pressure system, and the 1~5-level purification air-conditioning system shall comply with the regulations of the air duct of the high-pressure system.
2). The tightness inspection of the air ducts of the low-voltage system shall adopt random inspection, and the sampling inspection rate shall be 5%, and there shall be no less than one system. On the premise that the processing technology is guaranteed, the light leakage method is used for detection. When the test fails, the air leakage test shall be carried out according to the specified sampling rate; for the tightness inspection of the air ducts of the medium-voltage system, after the light leakage method is qualified, the system air leakage test shall be subject to random inspection. The sampling rate is 20%, and shall not be Less than 1 system; the tightness inspection of the air ducts of the high-pressure system, the air leakage test is carried out for all of them. If the sampling system is all qualified, it will be passed, and if it is not qualified, the sampling inspection should be doubled until all qualified.
5. Fabrication and installation of composite air ducts
See also the production plan for the production of composite air ducts; at the joints of composite air ducts, the joints should be firm and free of holes and cracks. When using plug-in connection, the interface should be matched without loosening, and the port gap should not be greater than 5mm. When flange connection is used, measures to prevent cold bridges should be taken. The installation of supports and hangers should be carried out in accordance with the provisions of product standards.
6. Air outlet installation
The connection between the tuyere and the air duct adopts a riveting gun to pull riveting. The wall of the air duct is on the inner and outer sides of the tuyere, and the space between the tuyere pipe wall and the air duct is sealed with a sponge strip or 8501 sealing tape. Two people are required to cooperate during installation. One person holds up the tuyere with his hands and levels it, and the other person rives the tuyere, and seals it with plastic sheeting after installation.
In short, in the installation process of ventilation ducts, the installers must install in strict accordance with the construction process and carry out quality control work. Only in this way can the installation quality of the ventilation ducts be guaranteed and meet the requirements for use.
