PCB proofing and baking problems in SMT chip processing plant

Circuit board proofing, whICh can be disassembLED and understood. PCB, that is, epoxy resin circuit board, proofing, that is, the production of product samples. Therefore, PCB proofing, that is, before the mass production of PCB circuit boards, is to confirm whether the circuit design and product production plan are feasible, and the number of samples commissioned by manufacturers is generally SMAll.

Charging

Is there charge for circuit board proofing? There is no absolute answer to this. The MARKet strategy, sample difficulty, sample delivery date, cooperation time and other reasons of circuit board manufacturers will affect its results. However, judging from the current development trend of PCB boards, the majority of manufacturers charge for PCB proofing, for the following reasons:

First, cost. Cost is an important indicator that any enterprise must evaluate. In the rigid circuit board industry, no matter how many pieces of circuit boards are produced, manufacturers must invest a certain amount of cost, such as labor, materials, technology, water and electricity. The technical fees and production processes invested in producing 1pcs and 1Kpcs PCBs are equal. A large number of samples will bring a certain amount of cost pressure to manufacturers;

Secondly, market factors. In PCB industry, "good and bad are mixed", and there are also real demanders, but there are also countless middlemen (especially individuals) doing trade. In order to minimize costs, such traders often cheat manufacturers to make PCB samples, take the samples and sell them to other traders or demanders, and then they will not order more batches, which leads to large losses for enterprises;

Third, the charge for proofing can attract the attention of manufacturers, thus ensuring the delivery date and quality to a certain extent.

Distribution of PCB proofing manufacturers

PCB belongs to the electronics industry, and the electronics industry is concentrated in the Pearl River Delta region of Guangdong Province. Especially, Shenzhen has become a world-class electronic market. Therefore, PCB manufacturers are mainly distributed in Shenzhen, Dongguan, Zhongshan, Zhuhai and other coastal areas.

Baking board problem in SMT small batch chip processing plant

Before SMT small batch patch processing plant's patch processing, there is a process that is not particularly noticed, that is, baking plate. In the electronic processing plant, some circuit boards that do not meet the requirements of Xi'an SMT chip processing due to long storage time and humidity in the storage environment can be removed of excess water after a reasonable baking process, which is conducive to the processing quality and makes SMT chip components and pads better combined. PCB baking is generally necessary only when the boards have been washed. Otherwise, more baking times will cause the boards to bubble. But generally, the original PCB will have a humidity card. First, confirm whether the humidity exceeds the standard. Sometimes even if there is a drying bag in it, it will be affected with moisture, so baking is necessary.

Xi'an SMT small batch patch processing plant

Precautions for baking boards before chip processing in small batch chip processing plants.

1、 Requirements: the temperature is 120 ± 5 ℃, generally baking for 2 hours, and the time starts when the temperature reaches the baking temperature. Specific parameters can refer to the corresponding PCB baking specifications.

2、 Temperature and time:

1. Bake at 120 ± 5 ℃ for 2 hours if the manufacturing date is 2 to 6 months.

2. Bake at 120 ± 5 ℃ for 4 hours when the manufacturing date is 6 months to 1 year.

3. If the seal is unsealed for more than 5 days within 2 months of manufacturing date, bake at 120 ± 5 ℃ for 1 hour.

4. The PCB that is one year later than the manufacturing date shall be baked for 4 hours at 120 ± 5 ℃ and re sprayed with tin before being put into production.

5. The circuit boards that have been baked must be processed within 5 days, and those that have not been processed need to be baked for another hour before they can be put online.

3、 Processing method:

1. components that will not be used after repair do not need to be baked.

2. Most small and medium-sized circuit boards are placed horizontally, which can be stacked with 40 pieces. The number of vertical circuit boards is unlimited. Take them out of the oven within 10 minutes after baking, and then place them horizontally at room temperature for natural cooling.

3. The medium and large circuit boards in SMT small batch SMT chip processing plants are mostly placed horizontally, which can be stacked for 30 pieces, taken out of the oven within 10 minutes after baking, and naturally cooled at room temperature.