Fabric air duct, also known as bag air duct and air distributor, is made of cloth woven from special industrial fiber materials.
The cloth bag duct, as the name implies, is an air duct like a cloth bag. It has the characteristics of flexibility and light weight, so it is simple and convenient to install, such as hanging curtains.
Therefore, the installation period of the project is short, which is nearly 90% less than that of the traditional air duct installation period, obviously reflecting its advantages in installation.
A complete project of fiber cloth air duct can be divided into three parts: field measurement and drawing design in the early stage, factory processing in the middle stage and field installation in the late stage.
For the late installation, mainly from the preparation and control before construction, installation process control, debugging, testing and acceptance of three aspects.
Picture 1. Preparation and control before construction
The installation process of the fabric duct system should be carried out on the premise that the site is clean after the installation of the civil works and all the equipment, especially the sand, paint, polish and engineering debris have been cleared.
The focus is mainly on the following aspects:
(1) Selection of installation mode
The scheme form of air duct is mainly composed of steel wire rope suspension, H-type slide rail suspension and T-type slide rail suspension. The reasonable installation form and hanging point can be selected according to different ceiling elevation and ceiling style.
Wire rope suspension
H-type slide suspension
T-shaped slide rail suspension
(2) Preparation of installation materials
1) Contact the forklift in advance to determine the length and tonnage of the plug plate before the air duct arrives;
2) When the air ducts are stacked, the labels on the containers should face outwards as far as possible or the container number can be clearly seen;
3) When the forklift is unloaded, extra attention should be paid to the insertion plate not to touch the goods to prevent scratches;
4) Accessories shall be classified and stacked according to the type of accessories. The mark of the container shall be placed outwards. If the ground is damp, a cushion shall be added.
5) The stacking place should be dustproof, moisture-proof and waterproof.
(3) Ensure the cleanliness of the construction site before installation
1) It is more reasonable to carry out installation work after indoor cleaning;
During installation, workers’ hands, installation tools, related contact pipes and equipment must be kept clean.
2) Workers should clean their hands before operating the air duct.
3) Finally, in order to ensure the cleanliness of the operating environment of the air duct, before the hanging of the air duct, it is necessary to start the air conditioning or ventilation equipment to blow out the residual dust, debris and other stolen goods in the unit to avoid entering the inside of the air duct.
Two, installation process control
(1) First of all, the expansion hook is fixed on the reference point that has been done with an electric hammer (using laser positioning). The expansion hook should be fixed firmly, with each spacing of 1.5 meters.
(2) The prepared suspension component is hung on the hook and fixed firmly. Its length should be confirmed according to the lifting height of the air duct.
(3) When making 1.5mm steel rope ring, the aluminum sleeve should be fixed at least three points, and the fixing tool should be steel wire pliers or vise. The indentation of the aluminum sleeve should be qualified as 0.5 times the thickness of the aluminum sleeve.
The suspension regulator is mounted synchronously with the suspension steel rope.
(4) Install the horizontal hanging steel wire rope assembly. When installing, pay attention to the size of the fastening force to prevent the jitter of the air duct after installation.
If the sliding rod is installed, the single length of the sliding rod is 3 meters;
When 28 pipe diameter slider is used (when the duct circumference is greater than 2 meters), cross-section reinforcement of the duct should be considered within 5 meters of the slider. Self-tapping bolts should be used for secondary reinforcement in the position of direct connecting parts.
When the sliding rod is used for hoisting, the air duct is connected with the sliding rod through the hook, and the sliding rod is fixed on the roof through the hanging steel rope.
The circumference of the air duct is less than 2 meters, and the slide rod is 19mm.
When 19mm slide rod is used for installation, gunpowder nails can be used for the suspension point. When 28mm slide rod is used for installation, expansion hooks are required in principle.
(5) Find the size and number of the corresponding air duct section through the air duct washing identification (containing the pipe diameter and pipe segment number), combined with the drawing of the air duct, and then connect it with YKK zipper.
For the tee, reducing and reducing pipe sections to be closed and fixed.
(6) Before hanging the air duct, if the inner support ring needs to be installed, it must be installed in advance. In the process of hanging, attention should be paid to the protection of the air duct, so as to avoid dirtying the air duct.
When installing, the assembly drawing should be strictly compared to ensure that the corresponding specifications and length of the air duct are installed in the corresponding position according to the drawing.
The air duct hanger shall be hung from the fan inlet to the other side. The hanger shall adopt special hooks (one section of the hook is connected with the air duct and the other section is hung on the slide rod or steel rope), and the spacing of the hooks shall be 500mm.
Debugging, testing and acceptance
After the precise installation process is completed, the debugging work of technicians is also needed to finally ensure the safe and stable operation of the system.
The specific work of senior engineers has the following aspects:
(1) Before debugging the system, it is necessary to clean the pipe of the system to ensure the cleanliness of the system, and then pull up the zipper between the entrance and the pipe.
(2) During installation and debugging, if the speed of the fan is adjustable, it should gradually rise to the working pressure to avoid the damage of the end of the fabric air duct system caused by instantaneous high pressure.
(3) After the fan is normally opened, observe the air duct system pipe inflation state, whether has been neatly formed along the entire suspension system straightening state, whether there are wrinkles and other phenomena in the middle.
If there is such a phenomenon, it should be checked and dealt with in time.