The final quality and production efficiency of plastic products are related to product design, mold design, auxiliary machinery, raw materials, injection molding machines, and injection molding processes

The impact of this relationship is approximately 40% in product design, 40% in mold design and processing, and 20% in raw materials, injection molding machines, and processes

Production efficiency is determined by production demand. If a product has a high production demand or requires long-term production, it is necessary to consider the difficulty and speed of production

In addition to considering appearance and functional structure, product design should also consider the adverse effects of processing, as it has a 40% impact on the final quality of the product

Usually, product designers are less knowledgeable about molds and injection molding, so it is necessary to form a planning team with senior mold designers and injection molding personnel to jointly review

Issues to consider during product design

1. Environment during assembly, transportation, and use (temperature and humidity, light resistance, negative charge, etc.), function, and lifespan.

2. Performance and material of the parts assembled with it.

3. Datum points for shape, dimensional accuracy, dents, deformations, flow patterns, glossiness, appearance, thickness changes, etc

4. Painting, printing, assembly, inlay, production quantity, number of holes

5. Expected cycle, molding machine capacity parameters, etc.

Mold Design and Processing

1. Estimated process parameters, temperature, pressure, time, and molding cycle time of each part

2. Filling, pressure maintaining, and cooling time

3. Determination of shrinkage rate, diameter, length, and arc of nozzle

4. Runner type, hot runner, cross-sectional shape, size, and branch configuration

5. Channel length, branching, pressure loss, temperature, viscosity, flow rate

6. Gate type, exhaust hole

7. Mold temperature, medium, and mold compressive strength

Mold Design and Processing (Cooling)

1. Calculation of cooling hole, medium temperature, flow, pressure and heat transfer coefficient

2. Configuration, position, shape, local cooling

3. Calculation of cooling time

Mold design and processing (ejection and extraction)

1. Diameter, quantity, position, sleeve, ejector plate of pins

2. Mold materials, local special materials, special processing, skateboards

3. Parting surface, insert type, groove extraction stop

4. Auxiliary equipment, extractor, special box, correction fixture, special fixture

5. Take out the machine fixture, inspect the fixture, and inspect the card

6. Possible problem prediction and response discussion

Form individual forms of the above questions, execute them according to the plan, and review them

Modal flow analysis is an ideal approach

What should be avoided in product design as much as possible

1. Do not vary the wall thickness too much, as it may affect the appearance, deformation, insufficient filling, etc

2. Avoid sharp transitions where wall thickness changes

3. The ratio of the cross-section to length of the extension bar will affect shrinkage and filling

4. Arc transition at corners

5. The threaded connecting rod should have holes and sufficient depth to avoid shrinkage and deformation