Mold factory talks about the main work content and precautions of process inspection management
by：Vowin Rapid Prototyping2023-02-20
1. Process inspection (PQC) process
When there is a change of injection mold production or shift production, PQC conducts the first piece inspection, and continues production if it is qualified, and continues production after adjustment if it is unqualified; PQC conducts inspections on products in the production process according to product categories; inspections pass and continue production If there is an abnormality, fill in the unqualified report, and the technical staff will convene the relevant department personnel to hold an MRB meeting; if the MRB meeting resolves the abnormal problem, continue production, otherwise until a solution to the problem is found.
2. Process inspection (PQC) control
1. First article inspection
When changing injection molds, repairing molds, shutting down for reproduction, or replacing materials, PQC must complete the first piece inspection within 30 minutes after the technicians adjust the product, fill in the inspection results on the inspection record sheet, and keep the records. The first part is placed in the designated position, and the first part of the injection mold is saved until the lower mold. The first item of a shift is saved until the end of the next shift, and it is automatically discarded after the first item of the next shift appears.
The production workshop judges the results according to PQC: if the product passes the inspection, continue to produce; for minor defects, inform the craftsman, adjust the machine and rectify the production; for serious defects, immediately stop production, and notify the technical, quality and related departments to hold a meeting for review.
2. Process inspection
The PQC personnel of Shanghai Mulan Injection Mold Factory conduct inspections on the production process in accordance with relevant standards such as inspection documents, drawings, and the first piece of startup. The appearance inspection of injection molds for A and B products is 8~10 pieces/90min, and for C products The frequency of appearance inspection is 8~10 pieces/120min, and the inspection cycle and sampling number for functionality, assembly, reliability, size and inspection are based on the inspection file (SIP), and the inspection results are recorded in the 'PQC Inspection Report'. The inspection frequency is adjusted by each injection mold factory according to the product characteristics of the factory.
3. Process exception handling
Shanghai Mulan Injection Mold Factory, aiming at the major defects of the products and problems in the process, the PQC personnel fill in the unqualified report, and after the confirmation of the workshop team leader, the technicians of the injection mold workshop, the production plan and other relevant personnel are called to analyze and propose countermeasures. PQC confirms the effect of the countermeasures proposed by the responsible unit. If it is invalid, PQC will return the countermeasures to the original responsible unit and propose again.
PQC found more than 5 major defects of the same kind in a row, and the defect rate of the process was too high, and the production rate was not higher than the last time. The MRB meeting was hosted by the injection mold technicians to deal with the problems.
4. Disposal of unqualified products
C. Unqualified products found in the production process should be marked as 'unqualified products' on the product identification sheet. After confirmation by the team supervisor, the products to be packaged should be placed in the non-conforming product area for isolation and control. Unqualified products are handled according to the conclusion of the MRB meeting .
3. Main work content and precautions of process inspection (PQC)
(1) Timely (after the upper mold of the injection mold is qualified for debugging or after the shift is handed over) do the first piece inspection, including the first piece at startup and the first piece in the shift.
(2) Feedback the unqualified information of the first piece inspection to the craftsmen and team management personnel in a timely manner, and issue the 'Unqualified Report' when necessary.
(3) When doing the first article inspection, it is necessary to explain clearly to the workers the quality self-inspection requirements of the product, and mark some key quality characteristics and control points on the product.
(4) Carry out patrol inspection according to regulations, the inspection cycle of key products is 90 minutes, and the inspection cycle of C-type products is 120 minutes.
(5) The number of inspection samples is 8~10 inspection frequency.
(6) During the inspection, carefully and carefully compare the samples.
(7) Strictly implement the regulations of the inspection documents during inspections to carry out sampling, sample delivery, inspection of size, color difference and assembly inspection, etc.
(8) During the inspection, it is found that the unqualified workers are caused by improper working methods, and the workers' practices are corrected immediately. If there is no change, it is necessary to feed back to the operator's superior supervisor and mark the unqualified products that have been produced. isolation.
(9) During the inspection, it is found that the unqualified products are caused by the production process of injection molds, and then timely feedback to the craftsmen and team leaders on duty, asking them to track and deal with the matter, and make a decision on the unqualified products that have been produced. Disposal and isolation; if the problem cannot be resolved, the superior supervisor should give feedback in time, and the superior supervisor will further organize and solve it according to the procedure.
(10) Defective products that are seriously defective and whose batch size exceeds 2 hours should be submitted to the relevant responsible department for rectification.
(11) For quality problems that cannot be judged, feedback should be made to the inspection supervisor, and the problem points must be clearly described when feeding back problems.
(12) PQC must fill in the inspection record form in time as required, especially the records of the inspection data must be true and reliable, and any record has the signature and date of the inspector, otherwise it will be regarded as an invalid record.
(13) PQC should promptly communicate with FQC the bad quality information found during the inspection process.