The complexity of the properties of plastic materials determines the complexity of the injection molding process. And the performance of plastic materials varies greatly because of different varieties, brands, manufacturers, and even batches. Different performance parameters may lead to completely different molding results.
The melt flows into the cooling cavity, dissipating heat due to heat conduction. At the same time, the heat generated by shearing may lose more or less heat than heat conduction, depending mainly on the injection conditions. The viscosity of the melt decreases with increasing temperature. In this way, the higher the injection temperature, the lower the viscosity of the melt, and the smaller the required filling pressure. At the same time, the injection temperature is also limited by the thermal degradation temperature and decomposition temperature.
The lower the mold temperature, the faster the heat loss due to heat conduction, the lower the melt temperature, the worse the fluidity. This phenomenon is especially evident when the injection rate is low.
The effect of injection time on injection molding is manifested in three aspects.
- Shortening the injection time, the shear strain rate in the melt will be increased, and the injection pressure needed to fill the cavity will also be increased.
- Shorten injection time, increase the shear strain rate in the melt. Because of the shear thinning of plastic melt, the viscosity of the melt decreases, and the injection pressure needed to fill the cavity also decreases.
- Shortening the injection time, the higher the shear strain rate, the greater the shear heat, and the less heat dissipated by heat conduction. Therefore, the higher the melt temperature and the lower the viscosity, the lower the injection pressure needed to fill the cavity.
As a result of the combined action of the above three conditions, the curve of injection pressure required to fill the cavity presents a “U” shape. That is to say, there is an injection time, and the injection pressure is small at this time.
JasonMould Industrial Company Limited, established in 2010, is a leading injection moulding manufacturer in China. JasonMould specializes in plastic mould production for household appliances, medical equipments, electronic equipments, safety equipments as well as monitoring system.
The company has over 15000 square metres factory. With plastic injection tooling divisions possessing different machinery and expertise, JasonMould offers tools from small and precise mobile phone parts to as big as automotive parts. Our tools are mainly exported to U.S.A., Europe, Japan and UK. JasonMould’s diversification strategy and full service has won compliment from customers all over the world.
Our mission is to provide our customers high quality moulding products and services. We aim to exceed our customers’ expectations of pricing, quality and on-time delivery. To achieve our mission, JasonMould:
- Commits to continually improve employee skills and efficiency,
- Provides our employees a clean and safe working environment,
- Upgrades machine technology and support equipment through a strict maintenance program, and
- Maintains customers’ tooling to its highest peak of performance
For more about custom manufacturer of plastic molding products,please visit https://www.jasonmolding.com/
Contact person: James Yuan
Company name: JasonMould Industrial Company Limited
Address: LongGang Village,LongXi Town,BoLuo County,HuiZhou City,GuangDong Province, China
Email: [email protected]