Quality control process in injection molding plant

1、The First Inspection, Record And Mark.

1.1 In the process of injection molding production, operators must do a good job of self-inspection records, test the appearance of the product, inspectors do a good job of signing and sealing the first sample of the product before starting the machine, and fill out the “first inspection report”, the production process to carry out product sampling work as required by the inspectors, each inspection project should be complete, and at the same time the three links of the packaged products, workbench products and random products on the machine to verify, find problems, timely Correction and coordination of processing.

1.2 The sampling inspector has the right to request the operator to rework the products that fail the self-inspection, and to record, mark and review the reworked products until reaches the product quality requirements, otherwise they are not allowed to be stored, and to ensure that the information is completely conveyed to the off-duty personnel during the handover shift to prevent the continued generation of defective products.

1.3 inspection supervisor every day to take back the inspection report and check the inspection records of the situation, the records are inaccurate or there are doubts to find the relevant quality inspectors to understand the confirmation, such as careless work, mistakes, lack of responsibility is required to inform criticism and, for many times not according to the implementation of the inspection work guidance personnel will consider changing jobs or other sanctions.

1.4 After the finished products of each injection section are qualified, the operator should make a good indication on the product outsourcing before moving to the next process. The finished products, semi-finished products, qualified and unqualified products of injection molding should be placed neatly according to the specified area and marked according to the principles of marking and traceability management, and the inspector has the right to control and coordinate the process, and has the right to request the staff to rectify or stop for rectification if the marking is not standardized.

2、Process In Confirmation.

2.1 Inspection and confirmation of products after material change and mold change

     Inspection process when the machine has a change of material, change of mold, quality inspection should be in accordance with the first inspection standards, item by item to confirm the appearance of the product, engineering dimensions, performance strength and component assembly degree and other quality parameters, investigate and understand whether the batch of materials used has changed, to facilitate the recording and prevention of defects.

2.2 Inspection and confirmation of products after mold repair

     When the mold is abnormally repaired and the trial sample is put on the machine, the quality inspection should confirm the appearance, engineering size, performance strength and component assembly degree and other quality parameters of the product item by item according to the first inspection standard, and compare with the previous samples to confirm that they are correct before putting them into mass production; if the mold is a major maintenance matter, it should be checked by the process group according to the above items before mass production, and if necessary, a long time is needed for verification tracking.

2.3 Inspection and confirmation of products after the newcomer’s operation

     When there is a change in the machine, newcomer operation, etc., the foreman, inspection must strengthen the number of inspections, clearly tell the product precautions and ensure that all employees understand, repeatedly check the proficiency of the newcomer operation in the process, abnormalities should be corrected in a timely manner, and if necessary, change the skilled staff to work to ensure the stability of quality.

2.4 Inspection and confirmation of products after shutdown

     During the production process, the machine is restarted due to special reasons, at this time, the machine is in an unstable state, the inspector should confirm the appearance of the product, engineering dimensions, performance strength and assembly degree of components and other quality parameters one by one according to the first inspection standards, and compare with the previous samples to make sure the product is qualified before mass production, and continue to follow up until the operation of the machine and product quality until the machine operation and product quality become stable.

2.5 Inspection and confirmation of products after process tuning

     Production process, product variation, workshop foreman or workshop supervisor to re-adjust the machine, when changing the machine molding parameters and the original problem is overcome, the inspector to reconfirm the quality of other inspection items whether the variation, various performance requirements, such as by increasing the temperature to overcome the product appearance of bad whether it will affect the physical properties of plastic and make the product brittle, etc., to avoid the occurrence of new bad problems caused by batch quality accidents occur.

2.6 Inspection and confirmation of the product of the handover process

     Workshop in the process of shift change, due to changes in personnel, new replacement materials not confirmed to have arrived at shift change time, the inspector of the previous shift forgot to thoroughly hand over or other reasons to the machine production quality hidden risks, for the risk that may cause batch quality accidents, the inspector of the succeeding shift in addition to strictly implement the inspection, must confirm the inspection sheet of the previous shift, self-inspection sheet, understand the use of materials, etc., timely familiar with the quality of the previous shift, the Take measures to ensure timely response to changes affecting process capability.

3、Defective Product Handling Process.

3.1 Concession release

     When the production of urgent needs and mold problems, the process can not be corrected or process control negligence caused by the occurrence of batch problems products, the strict implementation of the release review process, through the assessment can be let go, by the workshop to let go of the application for release, the quality of confirmation, superior review and approval to the relevant leaders to let go, the relevant supervisor to implement the responsibility and deductions and penalties for processing, without the approval procedures for the quality inspection of the products to be processed shall not release, warehouse management shall not enter the warehouse or transfer order.

3.2 Rework and re-inspection

     When the process control is negligent or the employees do not process the products according to the inspection requirements, resulting in bad batch needing processing, the workshop will arrange for the employees to rework the products outside the normal working hours in accordance with the “Management Regulations of Injection Moulding Workshop”, and the reworking will be completed after the sampling inspector has re-inspected the products before they can be billed for storage or transferred to the sequence.

3.3 Bad and end-of-life treatment

The release of products to implement the relevant provisions of the review process, through the review can not be reused, the need to implement the scrap or recycling shredded material processing, by the production plant application, confirmed by the relevant leadership signatures, leadership approval before scrapping or shredding, major bad accidents must be referred to the general manager ruling to deal with.

4、Process Improvement.

4.1 Problems found should be corrected in a timely manner, analyze, find ways to improve, and implement control according to corrective and preventive measures control procedures, contact the workshop to deal with the machine and mold that have not been improved have the right to implement downtime for rectification until the problem is solved before production.

4.2 The processing of defective products must be implemented to implement responsibility, the implementation of deductions and penalties, and the implementation of corrective and preventive measures through the investigation report, ordering the relevant departments and personnel to improve, after verification by the quality department is considered closed, the process of follow-up and feedback by the quality department is responsible for the implementation of arrangements, other departments must cooperate with the implementation.

4.3 The improvement of the injection molding process involves the modification of process documents or quality management documents should be in accordance with the requirements of the document and data management procedures, in response to the occurrence of abnormalities and the causes of the process out of control, to explore the shortcomings and omissions in the inspection specifications and work instructions, and gradually improve the process control documents and improve the process control capabilities.