Views: 4 Author: Xicheng EP LTD Publish Time: 2022-08-29 Origin: Xicheng EP LTD
PP plastic ductwork is also known as plastic air duct. The main production material is PP polypropylene. There are two kinds of conventional air ducts and flame retardant air ducts. PP plastic ductwork can be divided into round duct, rectangular duct, oblate duct and so on. Because pp material has strong corrosion resistance and toughness, it is favored by chemical plants, electroplating plants, laboratories and other enterprises that produce acid and alkali corrosive gases for ventilation. In terms of toughness, pp air ducts are more prominent than pvc air ducts, so in terms of service life, PVC air ducts cannot be compared.
1.Extrusion molding of polypropylene raw material by injection molding machine
The injection-molded PP plastic ductwork is fully automated, with uniform specifications and small errors, and can be customized in various lengths. At present, the size of the injection-molded air duct is only suitable for diameters below 600MM.
2. Bending and forming of polypropylene sheet
For large-diameter plastic air ducts, it is necessary to use a specific PP sheet for welding and production. Plastic air ducts with a diameter greater than 500 are prone to deformation, so flanges need to be used to reinforce the PP air duct body.
1.The specifications, types, properties, and thickness of PP air duct materials should conform to the design drawings and the national industry product standards.
2.Quality requirements during production:
(1) The specifications and dimensions of the PP plastic ductwork must meet the design requirements;
(2) The appearance requirements of PP air ducts must meet the requirements of straight folding angles, uniform arcs, parallel surfaces at both ends, and no warped feet;
(3) The inner surface of the air duct should be smooth, and it is strictly forbidden to have horizontal joints and set reinforcing ribs in the duct or adopt the reinforcement method of convex ribs. Minimize longitudinal seams at the bottom. When the bottom edge of the rectangular air duct is less than 800mm, there shall be no longitudinal seam on the bottom edge. All nuts, bolts, washers and rivets should be matched with the performance of the pipe, using materials that will not produce electrochemical corrosion, or galvanized, etc.; the bite seam of the clean air duct must be tightly connected, with uniform width and no holes. Half bite and bursting phenomenon.
(4) After the air duct is made, perform a wipe test again; check the inner surface of the air duct with white silk cloth, and there must be no oil stains and floating dust, and then seal the opening with plastic film. Installation, the stacking yard of the air ducts should be flat, and the number of stacking layers should be determined according to the wall thickness of the air duct and the diameter of the air duct. cause deformation.
(5) The gasket of the air duct connection flange should be closed-cell sponge rubber, and its thickness should not be less than 5mm.