The first is solid, and steel doors, windows, frames, and four corners are usually welded. The average angular strength required by the national standard must reach 3000N or more. In this regard, there is a need for regular welding equipment to ensure that there are no guarantees for small processing shops along the road. The other is that the connectors and fasteners should be solid, because the main material of the plastic window is PVC, and the wall thickness of its section is usually about 2.3mm, and it cannot withstand the hardware such as hinged window hinges. They need to have sufficient thickness of steel lining support inside, so before buying it is necessary to carefully observe the existence of a small amount of pounds or the possibility of cutting corners, the door and window after the finished product is not easy to check the thickness of the internal steel liner. The other is flatness, which includes the fact that the welding angle cannot be misaligned and the two windows cannot be uneven. This is mainly reflected in appearance, and it is also an important item that brings beauty to our vision. In the national standard, there are also concrete examples, such as: the difference between the height of the welding angle should be in the range of 0.3mm. It doesn't matter if you don't understand the national standard, but you have to look at his sample window and then ask for the quality of the appearance. The quality of the sample displayed by the average merchant is still OK. The third is accurate, mainly reflected in the accuracy of the size. It includes the size of the actual measurement of the hole and the size of the fan and frame after installation. Inaccuracy of the size often affects the opening of doors and windows and the sealing of doors and windows. The user can simply know that the ordinary door and window frame and the fan overlap are generally 8-10mm. If the size is too small (such as 4-5mm), the sealing performance is questionable. The fourth is the sealing performance. The dimensions mentioned above will affect the seal. If the manufacturer purchases the unqualified accessories, it will affect the seal. For example, inferior rubber bands used by some manufacturers will shrink within six months, resulting in a large gap between the glass and the fan. Rain and air can easily enter the room. Doors to buy building materials knowledge windows and doors glass hangers glass doors Shelf Pillar Roll Forming Line Change Rolling Machine,Shelf Roll Forming Machine,Shelf Pillar Roll Forming Line,Shelves Working Line Xinxiang Tianfeng Machinery Manufacture Co., Ltd. , http://www.tfrollforming.com
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