Share with you the criteria for plastic mould inspection

Fri Apr 14 14:55:57 CST 2023

Plastic Mould Inspection Standards

1.0 Scope of application.

Applicable to the acceptance inspection of all self-made and outsourced plastic moulds in our factory.

2.0 Inspection plan.

2.1 Definition of defect level.

Critical Defective: Defects that contradict national safety regulations or cause personal safety or property safety of the carrier or user.

Major Defective: A product item that exceeds the established specifications, loses or reduces its proper function, prevents normal operation or has the potential to reduce reliability. Minor Defective: A product item that exceeds the established specifications and reduces the satisfaction of use but does not affect the normal operation or reliability of its primary function.Plastic moulds

2.2 Acceptance Criteria (AQL%).




3.0 Inspection equipment

3.1 Vernier calipers

3.2 Multimeter

3.3 Hardness gauge

3.4 Tape measure

3.4 Micrometer

4.0 Appearance inspection criteria.

4.1 Choose a suitable standard mould base according to the size of the product, the external dimensions of the mould base should be in accordance with the industry standard dimensions.

4.2 The appearance of the moulds should be flat and clean on all six sides and should not be damaged.

4.3 The mould base must be of the same type and material (steel) as specified in the contract.

4.4 The slides and auxiliary devices made on the external surface of the moulds must be reasonably tight.

5.0 Mould structure (guide and ejector section)

5.1 The design of the mould structure must be reasonable.

5.2 The material of the guide pillar and guide sleeve (heat treatment hardness) should be reasonable, with good fit and no obvious gap, (with additional guide pillar auxiliary ribs)

5.3 The slider must be smooth, if necessary with heat treatment or oxidation (the material and hardness after heat treatment must be reasonable), with oil groove on the slider, and with spring return and stop screw, no damage to the appearance of the slider.

5.4 The slanting top must move smoothly, be heat treated or oxidised if necessary (the hardness after heat treatment must be reasonable), have oil grooves on the slanting top and be reasonably positioned.

5.5 The inserts and interchangeable moulds must be in good condition and undamaged, and can be easily removed and exchanged or randomly exchanged.

5.6 The ejector pin, return column and ejector plate must be smoothly moved, with a reasonable return spring and a reasonable stop-position device.

6.0 Cooling section

6.1 Reasonable arrangement of the cooling water circuit of the mould

6.2 Check that the circulating water circuit is clear and free from air or water leaks.

6.3 The size and pitch of the circulating water circuit connections must be in accordance with the requirements of the mould contract.

7.0 Pouring system

7.1 The size of the nozzle positioning ring is suitable for the injection moulding equipment, and the size and slope of the main flow path are reasonable.

7.2 Reasonable arrangement of the glue inlet and manifold, easy release of the water outlet.

7.3 The location and size of the glue inlet are reasonable, the glue is evenly distributed and the spout can be easily removed or automatically dislodged.

8.0 Product section

8.1 Good appearance of male and female moulds, no damage, clear corners of mould cavities, surface treatment in accordance with design requirements.

8.2 The size of the mould insert is suitable and the safety margin between the product edge and the edge of the mould insert is reasonable.

8.3 The exhaust position of the mould is reasonably designed, with no air inclusion or poor exhaust.

8.4 The dimensions of the mould are reasonable and the product produced is in accordance with the design requirements.

8.5 The parting surface of the product must not have pitting.

8.6 A movable wheel with the date, month, year and material identification is installed at a suitable location on the male part of the mould. (depending on the product) 8.7 The product must not have any mould pulling, shrinkage, deformation or other defects caused by the mould design.

8.8 The position of the ejector pin must be reasonable and must not affect the appearance of the product.