① General purpose bolts: There are many varieties, including hexagon head and square head.
② Bolts for reaming holes: When using, insert the bolts tightly into the reamed holes to prevent dislocation of the workpiece.
③Stop bolt: There are square neck and vertebra.
④Special purpose bolts: such as T-slot bolts, joint bolts, and anchor bolts.
⑤ High-strength bolt connection pair for steel structure: generally used for friction-type connection of steel structures such as buildings, bridges, towers, pipeline supports and hoisting machinery.
①General purpose nuts: mainly refers to hexagonal nuts, and square nuts.
② Slotted nut: mainly refers to the hexagonal slotted nut, that is, the groove is processed above the hexagonal nut. It is used in conjunction with a bolt with a hole in the screw and a split pin to prevent the relative rotation of the bolt and the nut.
③Lock nut: refers to the nut with locking function, including nylon insert hexagonal lock nut and all-metal hexagonal lock nut.
④Special purpose nuts: such as dish nuts, ring nuts, cap nuts, knurled nuts and embedded nuts, etc.
①Machine screws: Divided into many varieties due to different head and groove types. The head type has cylindrical head, pan head, countersunk head and half countersunk head. The head shape is slotted (in-line material) and cross grooved.
②Set screw: The set screw uses its tail end to prevent mutual displacement between the workpieces and transfer less torque
③ Hexagon socket screws: Hexagon socket screws are suitable for occasions where the installation space is small or the head of the screw needs to be buried.
④Special purpose screws: such as positioning screws, do not come off screws and eyebolts.
①Unequal length double-ended studs: suitable for occasions where one end is screwed into the body of the component for connection or fastening.
②Equal-length double-ended stud: suitable for matching the connecting end and the nut to play the role of connection or distance.
①Flat washers: used to overcome the unevenness of the supporting surface of the workpiece and increase the stress area of the supporting surface.
②Spring (elastic) washer: spring washer, etc.
③Return washer: There are internal tooth lock washer, external tooth lock washer, single ear stop washer, double ear stop washer, round nut stop washer, etc.
④Slanted washer: In order to adapt to the inclination of the supporting surface of the workpiece, an inclined washer can be used. There are square bevel washers for I-beam steel and square bevel washers for channel steel.
⑹Self tapping screws:
①Ordinary self-tapping screw: The thread conforms to the self-tapping screw thread, with a large pitch, suitable for use on thin steel plates or copper, aluminum, and plastics.
②Self-tapping locking screw: The thread conforms to the ordinary metric coarse thread, which is suitable for use in occasions requiring vibration resistance.
①Hot-forged rivets: Generally, they have larger specifications and are mostly used in locomotives, ships, and boilers. Usually, hot forging is required to shape the head.
②Cold-heading forming rivets: the general diameter specification is ≤16mm, and the head is usually formed by cold heading.
③Hollow and semi-tubular rivets: hollow rivets, semi-tubular rivets, etc.
④Special purpose rivets: headless rivets, tubular rivets, sign rivets, etc.
①Cylinder pins: cylindrical pins with or without thread, cylindrical pins with internal threads, cylindrical pins with external threads, elastic cylindrical pins, cylindrical pins with holes, etc.
②Taper pins: with or without thread cylindrical pins, internal thread cylindrical pins, threaded tapered pins, and taper pins with open ends.
③ Split pin: Generally, it is matched with the screw bolt with a hole and the slotted nut to prevent the bolt and nut from loosening.
① Retaining ring: Retaining ring with holes. Elastic retaining ring for shaft and split retaining ring for shaft.
② Wire retaining ring: wire retaining ring for holes, wire retaining ring for shaft and wire locking ring.
③Locking retaining ring for shaft parts: retaining ring locked with taper pin, retaining ring locked with screw, etc.
④Shaft end retaining ring: A shaft end retaining ring fastened with screws and a shaft end retaining ring fastened with bolts.
There are many varieties due to the different head and trough types. The head type has round head, countersunk head, half countersunk head, etc. The head groove shape is slotted (slotted groove) and cross groove.