The installation of spiral air ducts is a very important link, and the main work of ventilation and air conditioning engineering focuses on the installation of air ducts. Therefore, it is necessary to master the technical characteristics of multi-functional silencing pipes, be familiar with construction drawings, understand the relevant conditions of civil engineering and other professional types of work with this type of work, and verify whether the elevation, axis, reserved holes, and embedded parts of the air duct system meet the installation conditions. Prepare various auxiliary materials for installation, hoisting machines and other tools for installation, and mark and position the air duct system.

風管的組對：將成品或預制好的風管運安裝地點，結合實際情況進行檢查、復核，再按編號進行排列，風管系統的各部分尺寸和角度確認準確無誤后，即開始風管組對工作。風管各管段之間的連接采用法蘭連接，接口處要求嚴密不漏風。

Air duct assembly: Transport the finished or prefabricated air duct to the installation site, inspect and recheck it based on the actual situation, and then arrange it according to the number. After confirming that the dimensions and angles of each part of the air duct system are correct, the air duct assembly work begins. The connection between each pipe section of the air duct shall be flange connected, and the interface shall be tight without air leakage.

一次吊裝風管的長度要根據建筑物的條件，風管的壁厚，吊裝方法和吊裝機具配備情況確定，組對好的風管可把兩端的法蘭做為基準點，以中間法蘭為測點，拉線測量風管的連 接是否平直，偏差大時要進行調整，吊裝前，要對風管支、吊架，吊裝機具，選用吊裝機具的支、吊點，是否正確、牢固進行檢查，起吊前要仔細檢查，把桿、 滑輪、繩索等是否 固定，綁扎可靠并要吊裝范圍內的各種不因素。起吊時，要進行試吊，當離地200-300毫米時，停止起升，再一次對吊裝機具進行一次檢查，確認無誤后，繼續起升到所需高度。把風管固定在支、吊架上之后，才能解開繩索，拆移吊裝 機具。

The length of the primary air duct to be lifted should be determined based on the conditions of the building, the wall thickness of the air duct, the lifting method, and the allocation of lifting equipment. After the air duct is assembled, the flanges at both ends can be used as reference points, and the intermediate flange can be used as the measuring point. Draw a line to measure whether the connection of the air duct is straight. If there is a large deviation, it should be adjusted. Before lifting, the support and hanger of the air duct, the lifting equipment, and the support and lifting points of the lifting equipment should be selected to determine whether they are correct Check firmly. Before lifting, carefully check whether the rods, pulleys, ropes, etc. are fixed, and whether the binding is reliable. All unsafe factors within the lifting range must be removed. During lifting, a trial lifting should be carried out. When 200-300mm above the ground, the lifting should be stopped, and a comprehensive inspection of the lifting equipment should be conducted again. After confirming that there is no error, the lifting should continue to the required height. After fixing the air duct on the support and hanger, the rope can be loosened and the lifting equipment can be removed.

水平干管經找平找正并固定在支、吊架上后，就可進行支管的安裝。立管可在水平干管安裝前進行安裝，支架間距不應大于4米，每根立管固定件不應少于二個。風管水平安裝，水平度的允許偏差每米不應大于3毫米，總偏差不應大于20毫米，風管垂 直安裝，垂直度的允許偏差每米不應大于2毫米，總偏差不應大于20毫米。

After leveling and aligning the horizontal main pipe and fixing it on the supports and hangers, the branch pipe can be installed. The riser can be installed before the installation of the horizontal main pipe. The spacing between supports should not be greater than 4 meters, and each riser should have at least two fasteners. For horizontal installation of air ducts, the allowable deviation for levelness should not be greater than 3mm per meter, and the total deviation should not be greater than 20mm. For vertical installation of air ducts, the allowable deviation for perpendicularity should not be greater than 2mm per meter, and the total deviation should not be greater than 20mm.