Injection products need to prevent warpage and deformation

2021-03-23 10:57:52 admin

Injection products need to prevent warpage and deformation




Recently, a batch of plastic boxes worth 4,200 US dollars exported to Japan by a plastic products company in Ninghai were returned due to the inability of the lid to open freely, which could not meet the needs of customers.


Ningbo Ninghai Inspection and Quarantine Bureau immediately dispatched personnel to investigate the return. After investigation, it was found that the lids of this batch of pp plastic boxes were warped and deformed and could not be opened after the inner buckle was tightly closed. After further in-depth understanding, it was learned that because the company implemented piece rate management, employees adjusted the process parameters of the injection molding machine without authorization for the speed of the chart. The cooling time was reduced from 7 seconds to 5 seconds, which caused the pp lid to warp and deform, which directly caused the customer's functional requirements to be unachievable. .


It is understood that there are many factors that cause warpage and deformation of injection molded products. In addition to the performance of plastic raw materials, the most important factor is the setting of injection molding machine process parameters, including holding pressure, melt temperature, injection time and cooling time, etc. Both will affect the molding of injection molded parts to varying degrees.


For this reason, relevant companies are reminded that one is to strictly establish the awareness of establishing a quality company, to make it clear that the company is the first person responsible for product quality, and to strengthen employee training. The second is to scientifically set the production process. Before production, it is necessary to make an injection molding process table according to the product structure and material similarities and differences, combined with the first piece of test mold verification to ensure that the process parameters are adequate and sufficient. The third is to implement quality control of the production process, strengthen the monitoring and measurement of process parameters and product characteristics for key control procedures such as the injection molding process, and prevent product warpage and deformation quality problems caused by poor process and improper operation.