Certain components in a PCB assembly (PCBA) are sensitive to static charges. Improper handling, even at the slightest, may render the PCB defective or may create short circuits that make the electrical connections faulty. During assembly, proper handling must be practiced at all times. Proper storing and packaging of components and circuit boards must be implemented to avoid electrostatic discharge (ESD) and electrical overstress.
Proper management contributes in maintaining the quality of assembled products, as well as of the tools, machines, and materials used during assembly work. Proper management is categorized into at least three essential divisions: handling, storing, and packaging.
Correct Handling Management
Before proceeding to the assembly house, know the dos and don’ts of handling. Once in awhile, perhaps once a week, every worker in each area of the assembly house should be given a brief refresher of the precautions being followed before, during, and after assembly work. This is to ensure that no one is at risk of being exposed to contaminants and dangerous metallic residues, while at the same time keeping the PCB assembly safe from static discharge. Here are some tips and techniques in handling PCBA:
•Always hold the board or component by the edges. Use ESD-safe gloves at all times.
•Wear a wrist strap for grounding.
•Use two heel grounders to avoid electrical shock.
•Use only lotions and hand creams specially formulated for assembly work.
Storing Printed Circuit Board Assembly
In every industry, there will always be work in progress. To maintain the effectiveness of a circuit board and its components, these works-in-progress should be stored properly. Here are some tips in storing PCBA:
•Use bags or boxes with static shielding capabilities, anti-static properties, or static dissipative to store them.
•Use racks and trays with anti-static properties in stacking finished circuit boards that are ready for packaging. Never stack items on top of the other.
Sometimes, baking is also necessary before packing the finished PCB. It is the process of removing all traces of moisture that may have accumulated during storage and even in the packaging process. However, it must be noted that the process may affect the quality of soldered components.
Transportation after PCB assembly is associated with risks of electrical shock. Thus, proper packaging is important to keep the item free of any damage. ESD-safe packaging materials should be used to maintain quality. Some tips in proper packaging are as follows:
•Use only packaging materials that can keep moisture from entering the package.
•Place desiccants or silica gels to absorb any moisture that may seep through the outer packaging.
•Make sure that inner packaging is properly bundled to prevent damage due to accidental drops during transportation.
•Careful handling and transportation should be maintained to avoid causing shock to the PCB.
•Proper warnings and labels should be seen on the outer packaging so as to let the next transporter know that the product is sensitive to moisture, shock, and other environmental stressors.
•Humidity indicator can also be placed to ensure quality.
When the finished product leaves the PCB assembly house, it is hard to monitor how it is handled. So, it is very important for labels and warnings to be made visible on the box. Even though, your company has done every possible measure to ensure the quality of the product, be prepared for any returns due to mishandling and other accidents beyond the control of the company.
In cases of product returns, make sure to handle the situation in a professional manner and start the repair immediately. In addition, investigate and properly evaluate why a product was returned and what part of the process rendered it defective.