1. According to function and structure, power fittings can be divided into suspension clamps, tension clamps, UT clamps, connecting hardware, splicing hardware, protective hardware, equipment clamps, T-type clamps, busbar hardware, and guy wire hardware; according to application, they can be divided into line hardware and substation hardware.
2. According to product unit, power fittings are divided into malleable cast iron, forged, aluminum-copper-aluminum, and cast iron categories, a total of four units.
3. They can also be divided into national standard and non-national standard categories.
4. According to the main performance and application of fittings, they can be roughly divided into the following categories:
1) Suspension fittings, also known as support fittings or suspension clamps. These fittings are mainly used to suspend conductors and insulator strings (mostly used in straight-line towers) and to suspend jumpers to insulator strings.
2) Anchoring fittings, also known as fastening fittings or tension clamps. These hardware fittings are mainly used to fasten the ends of conductors, fixing them to the insulator string. They are also used to fix the ends of lightning protection wires and anchor guy wires. Anchoring hardware bears the entire tension of the conductor and lightning protection wire; some anchoring hardware even acts as a conductor.
3) Connecting hardware, also known as hanging parts. This type of hardware is used to connect insulators into strings and to connect hardware to hardware. It bears mechanical loads.
4) Splicing hardware. This type of hardware is specifically used to splice various bare conductors and lightning protection wires. The splice bears the same electrical load as the conductor, and most splicing hardware bears the entire tension of the conductor or lightning protection wire.
5) Protective hardware. This type of hardware is used to protect conductors, insulators, etc., such as equalizing rings for protecting insulators, counterweights to prevent pull-out from insulator strings, and vibration dampers and protective strips to prevent conductor vibration.
6) Contact hardware. This type of hardware is used to connect rigid busbars, flexible busbars to the outgoing terminals of electrical equipment, T-joints of conductors, and non-load-bearing parallel connections. These connections are electrical contacts. Therefore, high conductivity and contact stability are required for the contact hardware.
7) Fixtures, also known as power plant hardware or high-current busbar hardware. These hardwares are used for fixing and connecting various rigid or flexible busbars to post insulators in power distribution equipment. Most fixing hardware does not act as a conductor, but only serves to fix, support, and suspend. However, since these hardwares are used for high currents, all components should be free of hysteresis loss.