PCBA Tech - The management system of SMT workshop transfer line

The following is an introduction to the management system of SMT workshop transfer line

Purpose: To formulate transfer rules, reduce transfer time, improve production efficiency, and at the same time meet quality control requirements.

1. The job responsibilities of personnel from various departments when transferring:

1.1PMC, material warehouse (including tool room)

1.1.1 PMC arranges the production schedule, determines the production date, target capacity, and shipment date, and issues the "SMT Production Plan"

1.1.2 The material warehouse and tool room ensure that all direct and indirect materials (PCB fixtures, steel mesh, solder paste,red glue, etc.) are prepared on time.

1.1.3 Ensure that all materials can be loaded on the feeder before the production line is stopped (except for individual components that cannot be loaded on the feeder due to feeder or material problems), and try to ensure that the feeder is filled for the first time.

1.2SMT production

1.2.1 Clean up the bulk materials of the previous product (including auxiliary materials such as solder paste) before transferring, and clean the steel mesh scraper back to the warehouse. For the lead-free to lead-free process, the production line needs to be fully cleaned. The cleaning content includes printing,placement,reflow track cleaning, scraper, suction nozzle cleaning and recorded in the "Non-RoHS and RoHS Model Conversion Confirmation Form".

1.2.2 Before the transfer, the production line leader prepares relevant documents including "Operation Instructions","Bills of Materials","ECN Change Notice", etc. and carefully reads the production process documents.

1.2.3 Ensure that the disassembly and loading work after shutdown can be carried out promptly and quickly to avoid abnormal working hours.

1.2.4 Ensure that all operators' operations are carried out in accordance with the work instructions.

1.2.5 Coordinate the relevant departments to solve the related problems of the production line.

1.2.6 Ensure that all operators have relevant job certificates to complete their jobs independently.

1.3SMT project

1.3.1 Provide detailed, clear and easy-to-operate work instructions and "station table" to the production line.

1.3.2 Provide training on relevant production precautions and customer special production process requirements to all operators in the production line.The training objects for new products should also include the responsible technicians in this section.

1.3.3 For new products, PCB files, steel mesh, fixtures, solder paste,red glue,etc. should also be prepared in advance.

1.3.4 Ensure that the program is prepared in time and sent to the machine after the production line is shut down.

1.3.5 Confirm the condition of the machine and make preparations in advance before the start of the transfer, such as suction nozzle (please refer to "Nozzle Picking Component Type List" for details on suction nozzle selection), scraper, tube feeder, etc.

1.3.6 Preparation for furnace temperature test and furnace temperature test.

1.3.7 Optimize the working hours of each machine after one hour of normal production. The optimization standard is that the difference between the placement time of the two high-speed machines should not exceed 5Sec, so as to determine the production capacity.

1.3.8 After the standard production capacity is established, the production line must not adjust the machine placement speed at will. If there is a quality problem, it must be adjusted. Please communicate with the SMT engineering to monitor the production capacity in time. The department manager will decide whether to change the production capacity after evaluation. Production capacity formulation method: 3600Sec/bottleneck station time*number of puzzles * time relaxation rate (90%).

1.4 Quality Assurance

1.4.1 During the transfer process, check whether all the work of the production line is ready and check the material installation status according to the CHECK LIST.

1.4.2 If any defects are found during the inspection, a record shall be given, and production shall be stopped immediately if the circumstances are serious.

1.4.3 When the lead process is converted to lead-free process, the quality assurance check whether the production line is clean as required and recorded in the confirmation form (see "Confirmation Form for Conversion of Non-RoHS and RoHS Models")

Second, the work content of the material warehouse

2.1 After receiving the transfer notice, the material personnel in the material warehouse and tool room immediately send the prepared materials (including steel mesh, solder paste, jigs) to the production line half an hour before the shutdown of a product on the production line, and prepare the materials record.

Three, the work content of the SMT production line

3.1 The production line leader who received the notice half an hour in advance verifies the preparation of the warehouse materials and the corresponding preparations for the SMT project.

3.2 After receiving the notice, the leader of the production line arranges the inventory check of the previous product according to the production situation, to ensure the smooth completion of the previous product and the smooth progress of the line transfer, and record the start time of the line transfer.

3.3 The printer and the operator should confirm in advance whether the input quantity of the PCB of the previous product has reached the planned quantity, and after the last product is finished, take out the steel mesh and scraper to clean and return to the warehouse. The stencil and PCB of the next product are provided by the tool room for the printer to lead the transfer line. If there is a lead process to lead-free process, the printing equipment must be thoroughly cleaned.

3.3 The production leader is replaced with the corresponding process file, and the process file of the previous product is recovered and saved for the next production use.

3.4 SMT technicians go to the tin printing station in advance to check the model of the stencil and whether the stencil and scraper are deformed or damaged. Ensure that the OK stencil is used. If an abnormality is found, replace it in time and notify the engineer to repair it.

3.5SMT technicians confirm whether there are special requirements such as sealing the stencil according to the process; set the thimble position correctly according to the process (refer to the top PIN template or film chart); set the printing parameters correctly to ensure that the printing quality meets the requirements.

3.5 The printer confirms that the type of the solder paste meets the requirements of the process and whether the unpacking and use time of the solder paste is within the qualified range of the process regulations, and confirms whether the printing quality meets the process requirements.

3.6 IPQC will check the PCB, stencil and solder paste models according to CHECK LIST and make relevant records.

3.7 The operator uses the normal feeder to load the materials according to the "station table", and self-checks whether the feeder is used correctly, whether the components are in place, etc.

3.8 IPQC checks the materials according to the station table.

3.9 The technician should send the program to the machine immediately after the machine stops.

3.10 Technicians should follow the actual situation and try their best to do work such as track adjustment, thimble setting, nozzle replacement, inspection component identification, etc. at the same time as IPQC material inspection, and check whether the bulk material box is cleaned and placed in the correct position.

3.11 After IPQC checks the materials, check the thimble setting according to the top PIN template again (whether there is a top component).

3.12 The technicians check whether the mounting direction and position of the components meet the process requirements, and then place them on the next machine after they are correct.

3.13 After all the placement machines have pasted a complete board, reconfirm the direction and position, and send the sample board for the first inspection after it is correct.

3.14 The technician must ensure that the machine runs smoothly when the machine is turned into production. The operator can ask the technician to continue to adjust the machine if he finds that there is material throwing or deviation.

3.15 If there is a lead-free process, the track of the placement machine must be cleaned thoroughly.

3.16 When the last board of the previous product passes through the reflow furnace, the technician calls the program to run the furnace temperature consistent with this product, and adjusts the track width according to the PCB size.

3.17 If it is a new product or a product that has not been made in this reflow furnace, it can be passed through the furnace after the furnace temperature curve is tested.

3.18 If there is a lead process to lead-free process,the reflow furnace and track need to be cleaned completely;

3.19 After the transfer of all stations is completed,the engineer and quality assurance will confirm the quality from the loading machine to the furnace. After OK, fill in the end time in the confirmation column of the transfer report, and the transfer is completed.