Views: 5 Author: Xicheng EP LTD Publish Time: 2022-09-02 Origin: Xicheng EP LTD
PP ducting construction mainly uses processing equipment
Platform type sizing sawing machine.
Portable dicing saw.
Electrothermal plastic welding torch.
Woodworking planer, small hand hammer,
pistol drill, angle grinder, impact drill and other tools.
1. Before construction, the project manager and professional engineers should arrive at the construction site to determine the construction drawings, technical plans, construction plans, and construction cooperation plans, and report to the on-site engineer;
2. The on-site engineer must be familiar with the on-site construction environment and construction drawings, be familiar with the system layout, ventilation equipment, air duct, tuyere layout and design technical requirements, understand the relevant specifications, regulations and the air duct and tuyere manufacturing and installation process, according to the "Technical Disclosure System" Provide technical disclosure to the construction team leader.
1. GB50243-2016 Ventilation and Air Conditioning Engineering Construction Quality and Acceptance Specifications.
2. T-635 plastic air duct and accessories.
PP plastic ducting is often used for air supply and exhaust of corrosive gases. It is generally used in laboratory ventilation duct systems, factory exhaust gas discharge pipes, air conditioning ventilation pipes, chemical plant exhaust gas treatment, etc.
The technological process is: blanking - production - welding - reinforcement - transportation
The advantages of PP plastic ducting are corrosion resistance and good sealing; the processing flexibility is not as good as that of galvanized sheet. PP plastic ducting should reduce the diameter of the air duct as much as possible during processing, and the branch pipe can be opened on the main pipe to be reduced in diameter. When the length of the air duct exceeds 20m, a flexible flexible joint should be added. The thickness is determined according to the specification requirements and the diameter of the air duct. It must not be thin and thick to avoid reducing the toughness of the flexible joint. The surface of the soft joint should be flat and beautiful, and there should be no obvious distortion. The dimensions of both ends are equal, and the length of the soft joint is generally 200mm. connect. The air duct connection of the air duct in this project is in the form of sleeve socket welding, and all welds are fully welded.
PP rectangular air duct material table
Rectangular air duct processing specifications (mm) PP board material thickness (mm)
The blanking of this project is the factory processing welding and on-site production method
1. If the cutting of the air duct is to be processed in batches, the ruler can be set from the sawing machine, which can not only ensure the cutting speed, but also make the cutting accurate.
Because the PP material has a certain brittleness, the cutting saw blade must be kept sharp when cutting, and the cutting should be measured frequently to ensure the accuracy of the cutting air duct. A single small section of the board is lined with ink and then cut with a saw or hand-held saw. The sawn air duct material is flattened by tools, and the burrs can also be used for beveling in the angle grinder. The portable angle grinder has strong flexibility and can be used on site.
2. Processing of PP ducting.
The processing site of the air duct must be flat. If there are no special requirements for construction, the general specification of the air duct shown in the drawing is the inner size of the air duct. Now, the rectangular air duct is used as an example to explain the precautions for processing the air duct. The weld must be broken before welding. Processed air ducts The air ducts should be handled with care during handling.
3. Welding of PP ducting.
Air duct welding adopts hot air welding and PP special electrode. The specification stipulates: single-sided welding for plates below δ=5mm, U-shaped double-sided welding or X-shaped welding for plates above δ=5mm. Relatively speaking, the U-shaped weld has better strength. When welding, pay attention to whether the well-aligned air duct is twisted or not, the weld should be full, and the electrode arrangement should be uniform and beautiful. The surface of the welded air duct should be free of defects such as fracture and false welding, and the welding rod joints should be staggered. The contact surface of the welding rod should not have coke and fracture. If it occurs, it should be removed with a tool in time and re-welded. Since the external climate, temperature and airflow change have a great influence on the welding process, the air duct should be welded indoors. Due to the poor strength and toughness of PP air ducting, it is relatively bulky. In order to facilitate transportation, the processing length of each pipe section should be about three meters.
4. Reinforcement and transportation of PP ducting
Because the strength and toughness of PP air ducting are not large, it needs to be reinforced. Specification requirements: The 630-800 mm air duct in the straight pipe section should be reinforced inside the air duct, the thickness of the reinforced PP should not be less than the thickness of the plate of the air duct, the reinforcing strips and the air duct must be fully welded, and the reinforcing strips should be arranged evenly and neatly. Avoid skewing. In order to ensure the appearance and neatness of the lock angle surface. After welding, it should be placed in a good place to avoid damage and damage.