Common problems of automobile terminal welding

The plastic insulation material and conductive parts of the terminal are directly related to the quality of the terminal, which respectively determine the insulation and conductive properties of the terminal. The failure of any terminal will lead to the failure of the entire system project. It is said that prevention is the goal and analysis is the foundation. It is pointed out that from a certain application point of view, the function that the terminal should reach is: the center of the conduction of the contact part must be conductive and the contact is firm. The central part of the insulation that should not be conductive must be securely insulated. There are three common faults in automobile terminal welding:

1. The metal conductor inside the poor contact terminal is the central part of the terminal, which transmits the voltage, current or signal from the external wire or cable to the corresponding contact with its matching adapter. Therefore, the contact parts must have the structure, stable and reliable contact persistence and good electrical conductivity. Due to unreasonable structural design of contact parts, incorrect selection of materials, unstable mold, poor processing size, rough appearance, unreasonable external disposal process such as hot disposal electroplating, improper assembly, poor storage and use environment and improper operation, poor contact will be formed in the contact parts and matching parts.

2. The function of the poorly insulated insulator is to make the contacts adhere to the correct position arrangement, and to insulate each other between the contacts and the contacts, and between the contacts and the shell. Therefore, insulation parts must have electrical properties, mechanical properties and process forming properties. Especially with the widespread use of high-density and miniaturized terminal blocks, the effective wall thickness of insulators is getting thinner and thinner. This puts forward more stringent requirements for insulation materials, injection mold accuracy and molding processes. Due to the existence of metal residues on the surface or inside the insulator, external dust, flux and other pollution by moisture, organic data precipitates and harmful gas adsorption film and external water film blend to form an ionic conductive channel, moisture absorption, mildew, insulation data aging and other reasons, will form short circuit, leakage, breakdown, low insulation resistance poor insulation phenomenon.

3. The fixed bad insulator not only plays an insulating role, but also usually provides accurate neutralization and maintenance for the extended contact, and also has the function of positioning the device and locking it on the equipment. Poor fixation, light affect the contact of the formation of instant power failure, serious is the product collapse. Breakdown refers to the terminal in the plug state, due to data, design, process and other reasons to cause the construction of the plug and socket, the abnormal separation between the pin and the jack, will form a serious result of the control system power transmission and signal control infix. Due to unreliable design, material selection errors, improper selection of molding process, poor process quality such as hot disposal, mold, assembly, welding, and assembly is not in place, poor fixation will be formed.

In addition, due to coating peeling, corrosion, damage, plastic shell flash, crack, rough processing of contact parts, deformation and other reasons formed by the appearance of poor, due to the positioning lock with the size of the excess, poor processing quality divergence, total separation force is too large and other reasons formed by poor exchange, is also common disease, frequently occurring. These problems can generally be found and eliminated in time in the process of inspection and use. Without a reliable terminal, there is no reliable system engineering. Failure and reliability are two sides of a contradiction that correspond and relate to each other. After terminal reliability selection to find a variety of failure forms and failure mechanisms, can lead to a lot of experience and eliminate a variety of hidden dangers, for the improvement of design, process, inspection and application to provide a scientific basis, it is also an important basis for revising and formulating terminal technical conditions.