1. Ordinary external hexagon-widely used, characterized by a relatively large tightening force, the disadvantage is that there must be enough operating space during installation. You can use adjustable wrenches or open-end wrenches, or wrenches above glasses wrenches. Large operating space. 2. Cylinder head hexagon socket-is the most widely used of all screws, because it has a relatively large tightening force, it can be operated with an internal hexagon wrench, and it is very convenient to install. It is almost used in various structures, and the appearance is more beautiful and neat. The disadvantage is that the fastening force of the pin is lower than that of the outer hexagon. In addition, the inner hexagon is easily damaged by repeated use and cannot be removed. 3. Pan-head inner hexagon-rarely used mechanically, mechanical properties are the same as above, used under special environments and conditions. 4. Headless inner hexagon-must be used on certain structures, such as the top wire structure that requires a lot of tightening force, or where the cylindrical head needs to be hidden. 5. Countersunk head hexagon socket-there seems to be no such screw in the national standard. 6. Woolen nut-a frictionless surface, a structure that prevents sparks, and is rarely used mechanically. 7. Flange nut-I don't know much about it, there are blue nuts that need rust prevention. 8. Ordinary outer hexagon nuts-are used for ordinary screws.
Then, do you know how to pack all these parts? Fastener Counting Packing Machine!
