PCB News - Professionals deeply analyze the work content of the SMT processing process

Professionals deeply analyze the work content of the SMT processing process

1. Production planning process and preparation before production

The supervisor of the production workshop arranges the workshop plan reasonably according to the weekly and monthly plans of the planning department, combined with the supply of materials, and sends them to the elongation and technicians of each line of the workshop.

Stretching and technicians make preparations in advance according to the issued production plan, and check whether there is a steel mesh and whether the serial number is printed well

The BOM list is confirmed, the placement machine program is confirmed, and the production process is confirmed.

According to the production plan issued by the workshop, the material staff counts the production materials and the ingredients list, and sends them to each line after the count is completed. The solder paste and red glue are warmed up in advance according to the process requirements.

The equipment engineer, combined with the weekly and monthly plans of the planning department, prepares the program in advance for the new proofing products.

The operator prepares the materials for the next work order in advance according to the workshop plan, and tests the steel grid frame and tension.

Before production, the technician needs to transfer the program backed up in the computer into the placement machine, adjust the track thimble of the placement machine, check whether there are springboards, other errors, etc. in the program, and then load the material after confirming that it is correct. And adjust the use temperature of the reflow soldering product, and adjust the track.

The technician needs to check the solder paste and red glue printing quality of the printing operator before production, whether the material of the placement machine is good, and the FEEDER standard is placed, and the production can be started after all confirmations are correct.

2. Work management during production operation:

The printing operator needs to check the quality of the solder paste every 1 hour, check the stencil cleaning every 2 hours, test and record the thickness of the solder paste, and deal with simple faults of the printing machine. If the problem cannot be solved, the technician should be notified to solve it in time.

The placement machine operator needs to check the materials on the machine every 2 hours. If there is any abnormality in the material throwing inspection, the technician must be notified in time. The placement quality inspection, simple troubleshooting of the placement machine, and the unsolvable problems must be notified to the technician in time.

Inspectors conduct product inspections in accordance with the inspection specifications. If more than 3 problems with the same tag number are continuously found during the production process, the technicians shall be notified to deal with them in time.

During the production process, technicians need to check and confirm the machine throwing condition, solder paste printing quality, machine equipment operation condition, product quality condition every (two hours), check and record the reflow soldering temperature, and find that the problem needs to be solved in time. To solve the problem, the engineer or workshop extension and supervisor shall be notified in time.

The elongation of the workshop needs to do well in staff production discipline, standardized operation supervision and guidance at any time, and follow-up of the achievement of the production plan.

Engineers need to do a good job in the supervision and guidance of the operator's equipment standard operation, and the inspection of the machine's operation.

3. The process of solving abnormal production problems:

In the process of SMT processing, when there is an abnormality in the production that cannot be produced or the defective products with the same tag number and the same problem are continuously found to exceed 3PCS, the operator should immediately report to the technician, and the technician should analyze and solve the problem in time, and analyze the reason. Products or processes caused by machine failures, materials, processes, designs, human factors, and environmental factors do not conform to standards or regulations, and based on the causes, formulate solutions, and implement and track them.

If the material is abnormally elongated, it is necessary to fill in the abnormal form in time, indicate the reason for the abnormality and the defect ratio, and notify the production supervisor for confirmation and review. After the production supervisor confirms, it must be promptly submitted to the production manager for confirmation, and finally to the quality department for confirmation and analysis. If the material needs to be returned to the warehouse after the response to the abnormal order, the material staff shall be notified in time to return the abnormal material to the warehouse for processing.

When the equipment abnormality cannot be solved by the technician, the engineer must be notified in time. When the engineer is unable to repair, he must report to the production manager. After the production manager confirms, the engineer informs the manufacturer’s maintenance engineer to repair at the factory and register the cause of the abnormal repair result in the "equipment resume" superior.

For the abnormal feedback in the latter stage (welding, inspection, maintenance, quality), the defect that is responsible for the outflow of the shift is responsible for filling in the reason for the abnormality by the extension of the shift. The technician writes the reason for the outflow and the improvement countermeasures. After filling it out, it will be submitted to the workshop supervisor for confirmation. Elongation and technicians need to strictly follow the improvement measures, and the workshop supervisor is responsible for tracking and confirming the follow-up production improvement.

4. Placement machine program and new product management:

The engineer combined the monthly plan and the BOM and PCB number map provided by the engineering department to prepare the product program for the new product proofing in advance to ensure that the program can be produced before going online.

For permanent BOM changes issued by the engineering department, engineers need to modify the computer backup program immediately. After the modification is completed, copy the new program to the computer backup to overwrite the old program, including the program stored in the machine, to ensure that it is not needed before the product goes online It can be produced directly in the adjustment procedure.

When the new product is produced for the first time, the engineer needs to enter the program into the machine to adjust the coordinates, angles, and parts database to ensure the smooth and qualified production of the new product.

After the new product proofing is completed; the engineer needs to make a summary report on the product, and notify the production technicians, quality, engineering, and planning personnel of the proofing summary report in the form of e-mail to make follow-up improvements. The engineer needs to track the improvement in the next production. Need to give feedback to relevant personnel again.

Production technicians are not allowed to change the program privately (placement position number, material change, FEEDER position number change). The main rights of technicians to modify the placement machine are: program transfer, position coordinate adjustment, position angle adjustment, alarm information release, parts Adjustment of the database.

5. Machine equipment management:

Acceptance of equipment:

The equipment engineer handles the test machine and acceptance according to the requirements of the order contract and the specifications and performance data provided by the manufacturer.

When the supplier sends the equipment to the factory, the engineer is responsible for receiving and acceptance. After the acceptance is passed, the relevant content of the acceptance will be filled in the "Equipment Resume Form", and the relevant unit will provide comments and countersign. Finally, the general manager will sign and approve (according to the company's order approval authority), and send the "equipment resume" draft to the procurement.

Create equipment information:

After the equipment is checked and accepted, the engineer logs in the "equipment and fixture list", and the engineer establishes the equipment’s "equipment resume" and various equipment usage specifications and maintenance checklists. The specific contents of the resume include the product name, serial number, Value, payment, supplier/brand, shared logo, put into use date, damaged or scrapped date, period of use, and update the ledger to be shared for easy reference and understanding by all departments.

The equipment is numbered according to the coding principle, and is managed by the account.

All equipment accompanying materials are kept by the equipment engineer. When the user or technician needs to borrow them, they can obtain the borrowing from the equipment engineer. The equipment engineer must prepare the equipment random data account and borrowing account.

Maintenance work:

The production operator must do the daily inspection and maintenance of the machine in accordance with the maintenance inspection table formulated by the engineer.

Production technicians must do routine inspections, weekly maintenance, and reflow oven temperature tests in accordance with the maintenance inspection table formulated by the engineer.

Production engineers must do monthly and annual maintenance in accordance with the maintenance checklist. (Explained by PCB factory)