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How to identify the quality of phenolic composite air duct?

How to identify the quality of phenolic composite air duct?


1. Check the materials used

(1) Density: refers to the sandwich part, which should be greater than/equal to 50kg/m3

Identification method: pinch it by hand. The low-density sheet feels softer when it is pinched. It can also be weighed. Workers can feel its weight when moving the sheet.

(2) Aluminum foil: Due to the price increase of aluminum foil, it is a factor that affects the quality of the plate. Commonly used in the market are ordinary aluminum foil and coated aluminum foil. After coating treatment, the corrosion resistance of the aluminum foil can be greatly improved, thereby prolonging the service life of the air duct. At present, there are two types of aluminum foils commonly used in the market: 0.05mm~0.07mm, both of which meet the requirements of the "Regulations", but after all, there are differences in strength and life. There is at least a 10% difference in cost. Moreover, ordinary uncoated aluminum foil is generally used for 0.05 aluminum foil. Compared with the two, the material cost is 20% lower than that of 0.07 coated aluminum foil.

Identification method: Rub the surface of the aluminum foil hard, there will be black marks on the aluminum foil that has not been coated

2. Touch, press and press by hand

(1) Check the hardness, the harder you pinch, the better;

(2) Check the thickness of the outer protective layer, of course the thicker the better, the coated one is better than the uncoated one;

(3) Check the thickness of the interlayer. Generally, the standard thickness of the interlayer is 20mm, plus and the lower two layers are about 21mm, and the upper and lower 1mm can be used normally. If it is too thin, the flange will not be pinched tightly, and the duct will easily become disjointed; if it is too thick, the flange will simply not be pinched in and cannot be used at all;

(4) Check bonding, it refers to the bonding strength between the outer protective layer and the interlayer. At present, all products on the popular market are added with a non-woven bonding layer, which greatly improves the problem of weak direct bonding between the outer protective layer and the interlayer. Under high temperature conditions, it is normal for the local adhesion to be weak or slight bulging is normal, and the phenomenon of large-area peeling will not work;

(5) Check the flatness of the board, as long as there is no too deep grooves or depressions, it is normal and does not affect normal use. But if you find the plate bulging phenomenon, you need to pay special attention. In other words, as long as the outer protective layer is close to the interlayer, a little dent will not affect the normal use;

(6) Check the degree of fineness and uniformity of the interlayer.

3. Inspect the manufacturer and inspect the relevant qualifications of the manufacturer's phenolic board

When buying phenolic insulation board, you must choose a regular manufacturer, because the products produced by regular manufacturers are controlled by strict quality supervision departments. The products produced by such regular manufacturers have relatively few quality problems.

4. Acceptance method

(1) Perform a flame burning test on the phenolic board, and perform a burning test on the samples after construction to see if the real area has a fireproof effect. This acceptance method is very easy;

(2) The appearance acceptance method of the phenolic board, generally the color of the phenolic board of good quality is relatively smooth, there is no smell or odor, it will not be deformed by pressing hard, and there will be no cracks or wrinkles;

(3) Method of blistering: Phenolic board not only has the function of fire prevention, but also has the effect of waterproofing. You can put the sample into the water for the acceptance test. The quality is not deformed, softened, and peeled when exposed to water;

(4)Construction acceptance method: Even if the quality of the phenolic aldehyde analysis is passed, if the construction is not in place, it will cause the use effect. Whether it is flat, seamless, no displacement, no unevenness, etc., these are for whether a construction is qualified Acceptance Criteria;

(5)Product quality specification (contract), in order to ensure that the quality of the product is guaranteed in the later use process, some parameters and specifications of phenol must also be written into the contract when signing the contract, for example, the phenolic board of Class A and B fire protection There is a big difference. This is the acceptance standard for product specifications;

(6) Record some important aspects of construction with mobile phone video as a reference for acceptance standards.



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