China Stud Bolt Manufacturer introduces what are the ways to use hexagon socket countersunk head screws?
There is usually another situation, that is, the thickness of the fastened parts is less than the height of the head of the countersunk screw, which is common in sheet metal parts in mechanical equipment, such as the connection of the hinge of the chassis and the door and the box; the sheet metal of the equipment The connection between the cover and the equipment, etc.
Due to the small thickness of the part, the screw through hole of the fastened sheet metal part has become a conical hole completely. In this case, when the countersunk screw is tightened, the screw head is not a conical surface to compress the sheet metal part. , But the bottom of the screw head and the top of the threaded hole are squeezed. Although the screw feels that the screw is tightened, the sheet metal part is stuck instead of being pressed. In this case, although the screw feels that the screw is tightened, the sheet metal The gold piece is indeed not tightened. This is a very common situation.
Let me talk about the reasons for processing:
The head cone of the countersunk screw has a 90° taper angle. Usually the top angle of the newly purchased drill bit is 118°-120°. Some workers who lack training do not know this angle difference, and often use a 120° drill bit directly. Reaming, which causes the conical surface of the head of the countersunk screw to be difficult to tighten, but the line at the bottom of the screw head is difficult. This is also one of the reasons why the so-called countersunk screw cannot be tightened. This is not the fault of the screw.
Through the above introduction, China Bolts Factory hopes that you can simply refer to the content of this article in future use.
