Quality standards for conventional injection molded parts

I. Explanation of Common Defects

• First Measuring Surface: The top or side surfaces that users often see.

• Second Measuring Surface: Side surfaces, corners, or edges that users occasionally or rarely see.

• Third Measuring Surface: The bottom surfaces of assembled parts, components, or parts that are in contact with each other during assembly.

II. Inspection Conditions

1. This standard is based on the premise that there is no impact on functionality and is compared by visual inspection. It is not superior to limit samples and individual special standards.

2. Usually, visually inspect at a distance of 30 cm for 3 - 5 seconds. If a defect is found, move to 50 cm and observe for 3 - 7 seconds. Defects that are difficult to see and not very obvious are acceptable.

3. The inspection light source is the fluorescent lamp in the production factory, and the visual acuity should be above 0.7.

4. Observation angles: perpendicular to the observed surface and at 45 - degree angles above and below.

III. Technical Requirements and Inspection Methods for Surface (Appearance) Quality

IV. Routine Inspection Standards for Injection - Molded Product Quality - Functional Quality

1. Flash

• There should be no flash in any horn holes, key holes, switch holes, and all holes that cooperate with moving parts. Flash on hidden posts and ribs should not affect assembly and functionality. For exposed or potentially exposed flash (e.g., battery doors) that affects safety, it should not feel scratchy when touched by hand.

2. Deformation

• The deformation of the bottom shell supported on the platform should not be greater than 0.3 mm. The deformation of the front shell that matches the bottom shell supported on the platform should also not be greater than 0.3 mm. Deformation of other plastic parts is acceptable as long as it does not affect assembly functionality.

3. Dimensions

• Dimension requirements follow PARTSPEC. When there is no SPEC, refer to the sample and control according to the following tolerance requirements: (Note: Specific tolerance requirements are not provided in the original text, so it is left blank here)

4. Residual Sprue Gels

• a) For exposed or potentially exposed sprue locations (e.g., battery doors) that affect appearance and safety standards, the sprue location should be flat and meet safety standards, without being scratchy.

• b) For sprue locations with assembly requirements that are not exposed and do not affect assembly, the residual sprue gel should be controlled within 0.5 mm and not affect functionality.

• c) For non - exposed sprue locations with no assembly requirements and no impact on functionality, the residual sprue gel should be controlled within 1.5 mm. The fracture shape of the sprue location can be in a free state.