First, the external dimensional accuracy of the heat insulation strip

The inaccuracy of the external dimensional precision of the heat-insulating strip not only affects the quality of the profile composite, but also easily causes the deviation of the external dimensions of the composite heat-insulating profile and the generation of internal stress, which will have a direct impact on the guarantee of the "three qualities" of heat-insulating doors and windows (watertightness, airtightness, wind pressure resistance). Nylon extrusion to get precision size, there must be high-precision molds and add stabilizer nylon quality materials.

Second, the internal fiberglass structure of heat-insulating strips

The quality of the internal structure of the heat-insulating strip is the principle guarantee of the strength and stability of the profile.

1, the choice of glass fiber reinforced reasons

As nylon 66 has creep characteristics. That is, under a certain amount of external stress, its deformation increases with time and the phenomenon of increasing. In order to inhibit the creep properties of nylon 66, experiments have proved that the glass fiber reinforced nylon 66 is comparable to aluminum alloy in terms of strength, rigidity and heat distortion temperature. The danger of the insulation strips falling out from between the profiles due to thermal expansion and contraction effects is avoided.　　Now on the market a number of manufacturers in the sale of nylon 66 thermal bar, the test found that: some completely cheap mineral (such as calcium carbonate, talc, etc.) to fill, some use most of the minerals and a small amount of fiberglass (less than 10wt%) mixed filling method for enhancement; there are even nylon 66 to be added to the inside of some of the non-engineering plastics such as polypropylene, polyvinyl acetate, and so on!

2, Glass Fiber Arrangement

　　Glass fiber in the aluminum profile processing process hot strip horizontal + vertical arrangement, you can improve the longitudinal tensile strength, but also to improve the transverse tensile strength. But to let the glass fiber to achieve the horizontal and vertical arrangement must have 4040 aluminum profile accessories supply suitable molds, propulsion screws and special hexagonal fixtures, and these technologies are now only mastered by Germany.