Home / Company News / Specification for installation of PP air duct for exhaust air

Specification for installation of PP air duct for exhaust air

Views: 10     Author: Xicheng EP Ltd     Publish Time: 2022-01-19      Origin: Xicheng EP Ltd

The installation of polypropylene PP air duct is the most time-consuming and accident-prone link in the exhaust gas treatment system. Therefore, whether it is the production of the air duct before installation or the specification during installation, strict installation procedures are required to reduce accidents in the exhaust gas treatment system. happened. Let the source and editor take you to see the specifications before and after the installation of the air duct.

PP air duct

Polypropylene PP air duct

General provisions

(1) The general piping is based on the principle of open pipe installation. Unless otherwise specified, all pipelines shall not be buried in concrete.

(2) All indoor piping should be matched with other system pipelines, and should be installed at the highest point or close to the wall. The pipeline should be parallel or perpendicular to the wall, and the outdoor piping should be parallel or perpendicular to the building.

(3) The inside of the pipe should be removed first at the connection to prevent blockage.

Ventilation duct installation project

The scope of the project depends on the system requirements of the design drawing, and at least shall include the fabrication, installation and adjustment of exhaust pipes, air volume regulators, drain valves, manholes and accessories of the exhaust system. In the process exhaust pipe, the exhaust pipe of acid and alkali gas should be assembled with PP pipe. The required pipe thickness, joint method and reinforcement method should be manufactured according to the requirements of the design drawing and the regulations in the attached table.

3. Body reinforcement: The body of the air duct is processed with the plate used. When joining each unit of air duct, direct butt welding is not allowed, and a PP reinforcing ring with a width of more than 60mm (appropriately widened according to the diameter of the pipe) must be used to fix it. The welded PP air duct above 300? (inclusive) needs to be reinforced with PP flanges for every 1.5M air duct. The thickness should be more than 1.5 times the material of the air duct body, and its height should not hinder the installation of ceilings and lamps. Specific parameters See the seventh PP duct processing specification below.


(1) The air duct should be properly suspended (supported), and its own weight should not be added to the connected pipe line.

(2) The distance between the hanging supports shall not be greater than 3 meters.

(3) Single hanging is not used for air ducts with a diameter of 300mm (inclusive) and above, and the fixing ring must be sheet type. The specifications are shown in the table below.

(4) For pipelines with a diameter greater than (equal to) 850mm, in addition to the use of hanging braces, the distance between them is not greater than 10 meters, and a fixed bracket should be used to fix them on the beam. The material is the same as (4) above, and the specifications are shown in the table below.

(5) The screw holes on the support and hanger should be machined, and the holes should not be cut with gas.

(6) The position of the embedded parts of the air duct, component support and hanger is correct and firm, and the hanger adopts the bottom hanger and hard gasket.

(7) The boom of the hanger should be straight, the thread should be complete and smooth, the splicing of the boom should be welded, the lap length should not be less than 6 times the diameter of the boom, and should be welded on both sides, and the weld should be close to the end point of the expansion bolt.

Ventilation duct

Construction details of plastic PP air duct

(1) All air ducts shall be made according to the dimensions shown in the design drawings and detailed drawings, and their surfaces shall be flat and free of air leakage. However, in order to cooperate with the site, if changes must be made such as meeting conflicts, etc., the contractor shall explain the reasons and draw detailed drawings. The construction can be started only after the owner's approval.

(2) Unless otherwise specified, the air duct should be provided with air guides inside the right-angle turn, and the upper and lower ends should be firmly attached to the air duct.

(3) The connection between the branch air duct and the main air duct should be equipped with an air volume regulator for air volume adjustment.

(4) The hangers, supporting steel plates, angle iron screws, nuts and other devices are all made of galvanized material.

(5) The plastic air duct must be installed firmly, and the flexible air duct should be the shortest distance. Unless otherwise specified, the cross-sectional area of the plastic air duct connection shall not be reduced or recessed.

 Copyrights 2021 China Xicheng EP Ltd  All rights reserved. 
We use cookies to enable all functionalities for best performance during your visit and to improve our services by giving us some insight into how the website is being used. Continued use of our website without having changed your browser settings confirms your acceptance of these cookies. For details please see our privacy policy.