The truss purchase is considered from the following aspects:
Firstly: the welding level and technology of the truss, the high-quality truss, its welding must be precise, and the welder rules, the scale is accurate, there will be no screw hole misalignment. The defective soldering and the high quality are exactly the opposite, so it is very useful to identify it.
Secondly: the color, high-quality trusses are treated with tannic acid, the standard is bright silver, and the appearance of the truss is gray.
Thirdly: The two planes of the high-quality truss are polished by the grinding machine. Because of this, it is very good to ensure that the two planes of the truss are equally balanced. After the truss is welded, the two planes are not polished, the appearance is not flat, and the joint is not flat.
Now that you know, to distinguish the quality of the truss, we can start from the above three aspects, without having to know too much information about the quality of the product.