Any negligence in any link of the electronic component supply chain may lead to inherent deficiencies in the final product. And when a batch of components go through twists and turns and arrive at your warehouse, conducting scientific and standardized incoming inspection is like building the first line of defense for product quality, and it is also a crucial line of defense. Many teams just rely on "looking at the appearance" to get by, without realizing that a standard incoming inspection process can not only effectively intercept fake and inferior products, but also systematically reduce production risks and long-term costs. So, as a purchaser, how should we conduct an efficient and comprehensive "physical examination" of the received components?
Step 1: Document Verification - Verify the Authenticity of Materials
The first step in inspection before opening the packaging and touching the components begins with a strict review of the accompanying documents. This is not only a manifestation of management standardization, but also the cornerstone of tracing responsibility. You need to compare the delivery note provided by the supplier with your company's internal purchase orders item by item to ensure that the material model, quantity, packaging form, packaging requirements, etc. are completely consistent. Any slight differences need to be confirmed immediately with the purchasing personnel.
Next, it is to verify the 'Material Quality Inspection Report'. This document provided by the supplier is like a "birth certificate" for the material, detailing the key testing data of the batch of products at the production end. Please confirm that the batch number and production date in the report match the information on the physical label. A responsible supplier will provide truthful and reliable reports, and missing or confusing reports themselves are a warning sign. After completing the document review and confirming its accuracy, this batch of materials obtained the "admission ticket" to enter the next round of physical inspection.
Step 2: Outer Packaging and Label Review - Exploring the Clues in First Impressions
After opening the outer transport packaging, do not directly remove the components. At this point, your gaze should be focused on the smallest sales packaging of the material. The packaging material, size, and design of genuine products usually have their fixed standards. Check whether the reels, tubes, or trays used to hold electronic components are damaged, deformed, or heavily stained.
The most crucial step is to examine the packaging labels. The label is the "ID card" of the material, and the information must be complete, clear, and unaltered. You need to focus on:
Product name and model: Ensure 100% consistency with order requirements, any difference of a letter or number may lead to disaster.
Production batch number and date: Batch number is the key to tracing the production cycle of the original factory, while date reflects the age of the material. Logically contradictory production dates (such as "future" dates) or ambiguous batch numbers are all worthy of high vigilance.
Original factory information and place of origin: Check if it matches the original factory and place of origin you specified.
If there are traces of replacement or secondary pasting on the label, or if the label information does not match the internal physical object, the inspection should be immediately suspended and the inquiry process with the supplier should be initiated.
Step 3: Physical Appearance Inspection - Illuminate the Truth with Details
This is one of the most crucial steps in the inspection process, requiring inspectors to have keen observation skills and sometimes even the use of tools. It is recommended to develop standardized "Appearance Inspection Operation Guidelines" for different types of components to ensure uniform inspection standards. The main focus areas include:
Screen printing and labeling: Check the printing of trademarks, models, batch numbers, etc. on the component body under sufficient light. The silk screen of the original product is clear, firm, with sharp edges, and the font and logo proportions are coordinated. The silk screen of refurbished or counterfeit products often appears blurry, uneven in color, uneven in font thickness, and even fades after being gently wiped with anhydrous alcohol.
Pin/Solder End: The new component pins should present a uniform metallic luster, consistent color, and be arranged neatly and uniformly without any bending, oxidation, or soldering marks. The pins of refurbished parts are often the "hardest hit areas", with common states including dull color and oxide layer; Although re tinned, the luster is glaring and uneven; There is residual flux or slight scratches at the root of the pin.
Packaging body: Check whether the surface of the plastic or ceramic packaging body is smooth and flat, whether the edges and corners are neat, and whether the color is uniform. Devices that have been polished and refurbished often have fine horizontal scratches on their surface, or appear too bright or have localized discoloration due to high-temperature treatment.
Section 4: Electrical Performance and Functional Sampling Testing - Let Data Speak
For critical or high-value materials, after passing the appearance inspection, deeper performance verification is required. This step requires professional testing equipment and environment.
Basic electrical testing: Use tools such as multimeters to measure basic parameters such as impedance, capacitance, or diode characteristics between component pins, and compare them with typical values in the data manual or known good products. A serious deviation from the normal range means that the interior may have been damaged.
Function and parameter testing: Build a standard testing circuit (or use existing testing fixtures) to perform power on testing on the components. Verify whether its core functions are normal and whether key performance parameters (such as operating current, operating frequency, amplification gain, accuracy, etc.) fully comply with the specifications in the data manual. Many "refurbished parts" removed from old boards may still have basic functions, but their performance has significantly "shrunk" and are on the edge of specifications, which cannot guarantee long-term stability in the final product.
The sampling ratio should be determined based on the criticality of the material, the supplier's past performance, and the batch size. For new suppliers or high-risk materials, the sampling ratio should be increased or even full inspection should be conducted.
Step 5: Recording, Feedback, and Closed loop Management
The value of inspection work lies not only in "detecting" problems, but also in "preventing" problems. The results of each batch of incoming inspection, whether qualified or not, must be clearly and accurately recorded in the 'Incoming Inspection Report'. The report should include material information, inspection quantity, defect quantity, description of defect phenomena, judgment results, and inspector signature.
For qualified products, handle the warehousing process; For non-conforming products, they must be immediately isolated and labeled, and a "Non Conforming Product Report" must be issued to notify the procurement, quality, and R&D departments for review, and to decide whether to return, exchange, or grant special release. At the same time, these data will be entered into the supplier performance management system as an important basis for future supplier ratings and procurement decisions. Through this closed loop, incoming inspection has evolved from a passive "screening" action to a powerful engine that actively drives supply chain quality improvement.