DIN 965 Cross groove countersunk head screw is a kind of screw. The head is flat head, countersunk head, or semi countersunk head. Countersunk head screw can also be called flat head screw, countersunk head screw, half countersunk head screw. Generally, countersunk head screws are cross grooved.
DIN 965 Product Details
DIN 965 Application scope
Cross grooved countersunk head screws are commonly used in power equipment, electronic machinery, mechanical equipment, household appliances, digital products, water conservancy projects, decoration and construction, etc.
countersunk head screws are usually made of metal screws and wire blocks. After forming, they are in cylindrical shape. The head is flat head, such as an inclined surface around the side of the screw, so that the screw can lock the screw cap or other objects.
The top diameter of countersunk head screw is larger, and it can be round or hexagonal, so that tools such as screwdrivers or spanners can turn the screws.
The protruding top also prevents the screw from drilling too deep into the material and increases the pressure on the material. Countersunk screws can be removed or re tightened at will without loss of efficiency.
They provide greater force than screws and can be reused. The head of countersunk screw can be completely sunk on the product material used for countersunk screw, and the screw head will not hinder it.
Cross groove countersunk head screw is also a precision screw.
Generally, the size of small size is commonly used in the market. The specifications of countersunk head screws are m2, m3, M4, M5, M6 and M8. This refers to the diameter of the countersunk screw.
The countersunk screws are 4, 5, 6, 8, 10, 12, 14, 16, 20, 25, 30, 35, 40, 45, 50 and so on.
The measurement of countersunk screw length includes the thickness of countersunk head, that is to say, the length of countersunk screw is the total length including the thickness of the head.
Most countersunk screws are used after installation, and the surface of the parts can not be raised. There are two types of parts to be fastened.
The so-called thick one is that the thickness of the parts to be fastened is greater than that of the countersunk head screw. After the screws are tightened, some of the screw threads do not enter the threaded holes. In this case, the countersunk screws can be tightened.
There is usually another case, that is, the thickness of the fastening parts is less than the height of the countersunk screw head, which is common in the mechanical equipment, such as the connection between the hinge of the chassis and the door and the box, the connection between the sheet metal cover of the equipment and the equipment, etc.
Due to the small thickness of the part, the screw through hole of the sheet metal part is completely a conical hole. In this case, when the countersunk screw is tightened, the screw head does not compress the sheet metal part with the conical surface, but the bottom of the screw head and the top of the threaded hole are squeezed.
Although the sensing screw is tightened, the sheet metal part is stuck rather than pressed, Although the screw is felt to be tightened, the sheet metal part is not tightened. This is very common. Let’s talk about the processing reasons: the head of the countersunk screw has a 90 ° cone angle, and the top angle of the newly purchased drill is 118 ° – 120 ° generally.
Some workers who lack training do not know the angle difference at all, and often use a 120 ° drill to ream the hole directly. This causes that when the countersunk screw is tightened, it is not the cone surface of the head, but a line at the bottom of the screw head One of the reasons why the so-called countersunk screw can not be tightened.