1. Surface of the door hinge: check whether the surface material of the product is flat. If you see scratches and deformation, it is produced from waste materials (leftover materials). The appearance of this kind of hinge is ugly, making your furniture no grade.
2. Hydraulic performance of the door hinge : we all know that the key of the hinge is the function of a switch, so this is very important. The key is the damper of the hydraulic hinge and the assembly of rivets. The damper mainly depends on whether there is noise when opening and closing. If there is noise, it is a poor product. It also depends on whether the round speed is uniform. Is the hinge cup loose? If there is looseness, it proves that the rivets are not riveted tightly and are easy to fall off. Close it several times to see if the indentation in the cup is obvious. If it is obvious that there is a problem with the thickness of the cup material, it is easy to "burst the cup".
3, Screw of the door hinge: General hinges with two screws, all belong to adjusting screw, upper and lower adjustment screws, front and rear adjustment screws, some new hinges also bring the left and right adjustment screws, that is, the so-called three-dimensional adjustment hinge, generally with two adjustment stations enough. Tips: use a screwdriver to adjust the upper and lower adjusting screws three to four times, and then remove the screws to see if the teeth of the hinge arm are damaged, because the hinge arm is made of iron material, which is not as hard as the screws and is easy to wear. In addition, if the accuracy of the factory tapping is not enough, it is easy to slide or cannot be screwed. The front and rear adjusting screws are also some tests.