12 Parts of Fasteners
2021-03-22
1. bolt: a type of fastener composed of head and screw (cylinder with external thread), which shall be matched with nut to fasten and connect two parts with through hole. This type of connection is called bolt connection. If the nut is unscrewed from the bolt, the two parts can be separated, so the bolt connection belongs to the detachable connection. 2. stud: a type of fastener without head and only thread on both ends. When connecting, one end of it must be screwed into the part with internal threaded hole, the other end passes through the part with through hole, and then screw on the nut, even if the two parts are tightly connected into one see the whole. This connection form is called stud connection and also belongs to detachable connection. It is mainly used for the occasion where one of the connected parts is of great thickness, compact structure, or it is not suitable to use bolt connection because of frequent disassembly. 3. screw: it is also a kind of fastener composed of head and screw. According to the purpose, it can be divided into three types: Machine Screw, setting screw and special purpose screw. Machine screw is mainly used for a part with fixed thread hole and fastening connection with a part with through hole, and nut is not required (this connection form is called screw connection, which is also detachable connection; it can also be used with nut for fastening connection between two parts with through hole.) The set screw is mainly used to fix the relative position between the two parts. Special purpose Screws such as eyebolt are used for lifting parts. 4. nut: with internal screw hole, the shape is generally flat hexagon column, and there are flat square column or flat cylinder. It is used to fasten and connect two parts to make it a whole. 5. tapping screw: similar to machine screw, but the thread on the screw is the thread for special tapping screw. It is used to fasten and connect two thin metal members to make them a whole. Holes need to be made in advance. Because of the high hardness of the screw, the screw can be directly screwed into the hole of the member to form the responsive internal thread. This connection form is also a detachable connection. 6. wood screw: it is similar to machine screw, but the thread on the screw is a special rib for wood screw, which can be directly screwed into the wood component (or part), which is used to fasten and connect a metal (or non-metallic) part with through hole with a wooden member. This connection also belongs to a detachable connection. 7. washer: a kind of fastener with flat circular shape. It is placed between the support surface of bolt, screw or nut and the surface of connecting part, which can increase the contact surface area of the connected part, reduce the pressure per unit area and protect the surface of the connected part from being damaged; another kind of elastic washer can also prevent the nut from loosening. 8. retaining ring: it is used for installation in shaft groove or hole groove of machine and equipment, which can prevent the parts on the shaft or hole from moving left and right. 9. pin: mainly for parts positioning, some for connecting, fixing, transferring power or locking other fasteners. 10. rivet: a type of fastener composed of two parts of head and nail rod, used to fasten and connect two parts (or components) with through holes to make it a whole. This kind of connection is called rivet connection, which is called riveting. It is connected with the non detachable connection. Because to separate the two parts that are connected together, rivets on the parts must be destroyed. 11. assembly and connection pair: assembly refers to a type of fastener supplied by combination, such as combining a certain machine screw (or bolt, self supplied screw) with Flat Washer (or Spring Washer, lock washer); connecting auxiliary refers to a kind of fastener which is provided with a special bolt, nut and washer, such as high-strength and large Hexagon Head Bolt connection pair for steel structure. 12. welding pin: because of the dissimilar fasteners composed of light energy and nail head (or without nail head), fix it on one part (or component) by welding method so as to connect with other parts.
Mr. andy