Purchase cost of PCBA proofing materials

The basic process of purchasing can be divided into the formulation of purchasing plan, the occurrence of purchasing behavior, the supervision of purchasing process, the tracking of manufacturers' production, the delivery of goods, the inspection of goods, the warehousing, storage and delivery of products. Supply and marketing settlement, etc.

Procurement cost refers to the cost incurred in the process of PCBA proofing and material procurement. Some costs are visible, that is, those that can be easily analyzed or derived directly from financial statements. Some are invisible, that is, difficult to analyze or easy to ignore. These two kinds of costs are divided into "explicit cost" and "implicit cost". The following hundred thousand into electronic Xiaobian for you to do a simple explanation.

The first type is: explicit cost, including procurement plan cost, raw material cost, semi-finished or finished product cost, procurement management cost, transportation cost, acceptance cost, etc.

An accurate procurement management planning economy can accurately predict and master the production and development plan of an enterprise, and enable Chinese enterprises to minimize the occupation of procurement funds on the premise of meeting their own product design, production and living needs. At the same time, they also need to conduct a relatively comprehensive analysis of the supply market information, adjust the order plan, evaluate and select suppliers. The preparation method of procurement work plan can be said to be the first link of the whole procurement system process, and its expenditure is also called the preparation cost of procurement plan.

The cost of raw materials, semi-finished products and finished products refers to the price of the commodities purchased. There are many reasons that affect the price of materials purchased, including commodity market price, commodity quality, market supply and demand relations, etc.

The cost incurred in the process of purchasing business is the cost of purchasing management. Including labor costs, bidding costs, construction costs, entertainment expenses, office expenses, travel expenses, etc.

Transportation costs must be incurred for the materials purchased. This is the transportation cost. Choose scientific, economic, reasonable mode of transportation, will save a lot of transportation costs for enterprises. Enterprises with a certain scale and strength should pay more attention to the transportation link, and realize the standardization and specialization of the procurement process. Choose the right mode of transportation, planning reasonable transportation routes, save freight, reduce procurement costs.

Purchased raw materials, semi-finished products or products need to be inspected before storage. In order to prevent the warehousing of unqualified or substandard raw materials, semi-finished products or semi-finished products, the warehousing of this level of materials must be strictly checked. Once the product is purchased, it is found that the product quality is unqualified, damaged, insufficient quantity or even wrong variety. The enterprise not only faces the problems of variety, quality and quantity, but also needs to return the time cost. It may also cause the production line to stop causing the shortage of raw materials or semi-finished products and the shortage of production cost.

What are the quality and detection points of small batch PCBA proofing? In order to achieve the quality management goals of SMT patch proofing and processing enterprises with primary qualification rate and high reliability, it is necessary to effectively control the Printed Circuit Board Design research scheme, components, data, process, equipment, rules and regulations. Among them, based on the development process can be controlled in SMT patch proofing industry is particularly important. In each step of the SMT patch proofing and manufacturing process, scientific and reasonable detection and analysis methods should be followed to avoid various problems, defects and hidden dangers, so as to truly enter the next process.

SMT patch proofing production processing and welding technology testing is to improve the overall testing of the products of welding enterprises.

Generally, the points we need to pass the detection are:

1, detection and spot welding surface quality is smooth, there are holes, holes, etc.;

2, spot welding is crescent shape, there is no more tin less tin, there is no monument, bridge, parts using mobile, missing pieces, tin beads and other defects.

3. Whether there are defects of different development levels among the components;

4. Search for defects such as short circuit and conduction when welding, and check that the color of the printed circuit board design surface can change.

The quality inspection of surface mount chip calibration includes feed inspection, process inspection and surface mount inspection. Quality problems found in process inspection can be corrected according to the rework situation. The cost of incoming material inspection, solder paste printing and rework of unqualified pre-welded products is relatively low, and the impact on the reliability of electronic products is relatively small. But the rework of defective parts after welding is completely different. In addition to working hours and materials, components and circuit boards can be damaged by post-weld repairs, which require de-soldering and re-soldering. According to defect analysis, the quality inspection process of smt chips can reduce the defect rate and reject rate, reduce rework and repair costs, and avoid quality hazards at the source.

In order to guarantee the welding quality of printed circuit board (pcb), it is necessary to pay attention to the process parameters of reflow welding. If the parameter setting is wrong, the welding quality of PCB cannot be guaranteed. Therefore, under normal conditions, furnace temperature must be tested twice a day, low temperature test once. Only by constantly improving the temperature curve of welding products and setting the temperature curve of welding products, can the quality of processing products be guaranteed.

Professional SMT chip proofing quality inspection must be very strict. Only strict quality inspection can guarantee the reliable quality of SMT products. The Pearl River Delta region is full of chip processing factories. It can even be said that nine out of ten industrial zones have electronic processing plants. If you want to survive and thrive in this environment, ensuring the quality of your products is a prerequisite.