Mould design standards and specifications

1. General design principles

1. Standardisation and interchangeability

Prioritise the use of standard mould bases (e.g. the Longji standard) and components to enhance mould versatility.

Standardise parameters such as mould base dimensions, ejector pin holes and cooling channels to reduce manufacturing costs.

2. Practicality principle:

Avoid redundant functions and pursue designs that are simple to manufacture, have a long service life and are cost-effective.

Parting line designs should be simple and reasonable in terms of strength and ease of maintenance.

3. Materials and hardness

Select materials based on product characteristics (e.g. high temperatures or corrosive environments) and ensure the mould base meets hardness standards.

2. Key design specifications

1. Structural design:

Guide mechanism: The clearance between the guide pins and the guide bushings must be ≤0.02 mm on both sides, and there are high requirements for the surface finish.

Ejection system: Ejector pins should be distributed symmetrically to prevent product deformation. Small ejector pins (Φ2 or smaller) should use a double-layer structure.

Cooling system: The cooling channels should be designed to pass through the deep rubber moulding areas of the mould cavity to avoid interference with the ejector pins/screws.

2. Venting and overflow

The depth of venting channels should be less than the material flash value (e.g. 0.03 mm for ABS). Venting inserts can be added to areas prone to trapped air.

3. Tolerances and dimensions:

Dimensions are annotated using the coordinate method, with views projected using the third-angle method.

Functional dimension tolerances must be confirmed with the manufacturing department and allowance for mould modifications must be made.

III. Manufacturing and Inspection Standards

1. Machining requirements:

The deviation of the mould base reference edge must be ≤0.1 mm and the angular deviation must be ≤0.1°.