First, poor contact

Metal conductors in metal stamping parts, metal terminals and wiring terminals are the core parts of terminals, which transmit voltage, current or signals from external wires or cables to the corresponding contacts of their matching connectors. Therefore, contacts must have excellent structure, stable and reliable contact retention and good electrical conductivity. If the structural design of the contact piece is unreasonable, the material selection is wrong, the mold is unstable, the machining size is out of tolerance, the surface is rough, the surface treatment technology such as heat treatment and electroplating is unreasonable, the assembly is improper, the storage and use environment is harsh and the operation is improper, which will cause poor contact at the contact part and the mating part of the contact piece.

Second, poor insulation

The function of the insulator is to keep the contacts in the correct position arrangement, and to insulate the contacts from each other and between the contacts and the shell. Therefore, the insulating parts must have excellent electrical properties, mechanical properties and process formability. Especially with the wide use of high-density and miniaturized terminals, the effective wall thickness of insulators is getting thinner and thinner. This puts forward more stringent requirements for insulating materials, injection mold accuracy and molding technology. If there are metal residues, surface dust, flux and other pollution on or inside the insulator, organic material precipitates and harmful gas adsorption films fuse with the surface water film to form ionic conduction channels, moisture absorption, mildew growth, aging of insulation materials and other reasons, it will cause short circuit, leakage, breakdown, low insulation resistance and other poor insulation phenomena.

Third, poor fixation

Poor fixation, light impact on contact reliability and instant power failure, serious product disintegration. Disintegration refers to the abnormal separation between plug and socket, pin and jack caused by the unreliable structure of the terminal in the plugged state, which will lead to the serious consequences of the interruption of power transmission and signal control of the control system. If the design is unreliable, the material selection is wrong, the molding process is not selected properly, the quality of heat treatment, mold, assembly, welding and other processes is poor, and the assembly is not in place, etc., it will cause poor fixation.

Metal stamping parts, metal terminals, wiring terminals, poor appearance due to peeling, corrosion, bruise, plastic shell flash, cracking, rough processing of contact pieces, deformation and other reasons, and poor interchangeability due to out-of-tolerance positioning and locking fit size, poor processing quality consistency, excessive total separation force and other reasons are also common and frequently-occurring diseases. These faults can generally be found and eliminated in time during inspection and use.