The difference between flat head screws and countersunk head screws
Flat head screw: The axial surface of the screw body is formed with axially extending threads, and there is at least one slot at the end. A chip groove is dug toward the center of the screw at the notch. The chip groove must penetrate into the screw body and exceed the center line by a predetermined angle. The main function is to prevent the chip from blocking the notch.
Countersunk head screw: The head of the screw is a 90-degree cone, and the head has a tool tightening groove, such as a slot, a cross groove, a hexagon socket, and a hexalobular socket.
The difference between flat head screws and countersunk head screws:
One: the contact surface is different, the contact surface of the flat head screw and the workpiece is the bit plane, and the countersunk screw is the bit cone;
Second: the force is different, the force of the grub screw is larger, and the force of the countersunk screw is smaller;
Third: the combination is different, flat head screws can be used in combination with this flat washer, and countersunk head screws can only be used in combination with tapered washer;
Fourth: The use method is different. The flat head screw can go deep into the counterbore or exposed to the outside, but the countersunk head screw is generally only inside the counterbore.