Tag Archive for: dimensional accuracy

What are the molding methods in the silicone industry?

Silicone, as a widely used material in various fields, has various molding methods, each with its unique advantages and applicable scope.

Compression Molding

Compression molding is the most common and fundamental process in the production of silicone products. The core of this process lies in the use of molds, and the shape of the molds directly determines the shape of the final product. The specific process of compression molding is as follows:

1. Raw material preparation: Mix raw materials such as silicone rubber, vulcanizing agent, color masterbatch, etc. in a certain proportion, and then mix them evenly through a rubber mixing machine. The blended silicone raw materials should have appropriate viscosity and flowability for subsequent molding operations.

2. Mold design and production: Design and produce corresponding molds based on the shape and size of silicone products. Molds are usually made of steel with high hardness and precision to ensure the dimensional accuracy and surface smoothness of the formed products.

3. Molding operation: Place the mixed silicone raw material into the mold, and then place the mold into the vulcanizing machine for heating and pressure. At a certain temperature and pressure, silicone raw materials undergo sulfurization reactions to form the desired shape. The temperature for compression molding is usually within the high temperature range to ensure that the silicone raw material can be fully vulcanized.

4. Demolding and post-processing: After vulcanization is completed, remove the mold from the vulcanizing machine and perform demolding operations. After demolding, silicone products still need some post-processing, such as trimming burrs, cleaning, inspection, etc., to ensure the quality of the product.

The compression molding process has the advantages of high production efficiency, high product size accuracy, and suitability for large-scale production. However, this process also has some drawbacks, such as high mold costs and limited product shape. Therefore, when choosing compression molding, it is necessary to comprehensively consider factors such as specific product requirements, production conditions, and costs.

Silicone molding has three ways of molding, injection and extru

Injection molding

The injection molding process has higher quality requirements. It combines the advantages of liquid silicone and plastic, making the product have excellent thermal stability, cold resistance, excellent electrical insulation performance, and will not produce toxic substances during combustion. This characteristic makes injection molded silicone products occupy an irreplaceable position in fields such as health products, automobiles, baby products, medical supplies, diving products, kitchen utensils, and seals.

The specific process of injection molding is as follows:

1. Raw material preparation: Store the liquid silicone raw material in two components, A and B. Before molding, mix the raw materials of components A and B in a certain proportion to ensure stable product performance.
2. Mold design and production: Similar to compression molding, design and produce corresponding molds based on the shape and size of silicone products. The mold needs to have high precision and temperature resistance to adapt to the high temperature and high pressure environment of injection molding.
3. Injection molding: Inject the mixed liquid silicone raw materials into the mold through an injection molding machine. Injection molding machines are usually composed of injection systems, mold clamping systems, heating systems, cooling systems, etc. At a certain temperature and pressure, liquid silicone gel undergoes vulcanization reaction to form the desired shape.
4. Demolding and post-processing: After vulcanization is completed, remove the mold from the injection molding machine and perform demolding operations. The silicone products after demolding also need to undergo post-treatment to ensure product quality.
The injection molding process has the advantages of high precision, high smoothness, and high production efficiency. However, this process requires high equipment and molds, and the cost is relatively high. Therefore, when choosing injection molding, it is necessary to comprehensively consider factors such as product quality requirements, production scale, and cost.

Extrusion molding

Extrusion molding is the process of using a silicone extruder to extrude silicone raw materials into shape. This process is commonly used to produce tubular silicone products with longer shapes that can be cut freely, such as silicone tubes, silicone strips, etc. The specific process of extrusion molding is as follows:

1. Raw material preparation: Similar to compression molding and injection molding, raw materials such as silicone rubber, vulcanizing agents, colorants, etc. are mixed and blended to meet the requirements of extrusion molding.
2. Extruder debugging: Select a suitable extruder based on the shape and size of the silicone product and debug it. Extruders are usually composed of screws, barrels, heads, heating devices, etc. During the debugging process, it is necessary to ensure that the parameters such as screw speed and heating temperature meet the product requirements.
3. Extrusion molding: The blended silicone raw material is added to the extruder, and under the rotation of the screw, the silicone raw material is gradually pushed towards the machine head. At the machine head, silicone raw materials are extruded into the desired shape through a mold. During the extrusion molding process, it is necessary to control the speed of the screw and the heating temperature of the extruder to ensure the dimensional accuracy and surface quality of the product.
4. Cooling and cutting: The extruded silicone products need to go through processes such as cooling and cutting. Cooling can be achieved through water or air cooling to quickly solidify silicone products. Cutting can be done manually or automatically to cut silicone products into the desired length.

The extrusion molding process has the advantages of high production efficiency, regular product shape, and suitability for continuous production. However, this process also has some drawbacks, such as relatively low product size accuracy and high mold costs. Therefore, when choosing extrusion molding, it is necessary to comprehensively consider factors such as product shape requirements, production scale, and cost.

summary

The three main molding methods in the silicone industry – compression molding, injection molding, and extrusion molding – each have unique advantages and applicability. Compression molding is suitable for the production of various silicone products and has the advantages of high production efficiency and high product size accuracy; Injection molding requires higher quality and is suitable for fields such as health products and automobiles, with characteristics such as high precision and high smoothness; Extrusion molding is suitable for producing tubular silicone products with longer shapes that can be cut freely, and has the advantages of high production efficiency and regular product shapes.

/by

What are the processing techniques for silicone products and what are the differences in the techniques?

The processing technology of silicone products mainly includes the following:

Compression molding:

Process description: Place silicone material into a mold and cure it into shape through heating and pressure. Application: Widely used in manufacturing seals, gaskets, buttons, etc. Features: Simple process, low cost, suitable for large-scale production.

Injection molding:

Process description: After heating and melting the silicone particles, they are injected into the mold and cooled to form. Application: Suitable for manufacturing silicone products with complex shapes. Features: High production efficiency, suitable for large-scale production, but high equipment cost.

Extrusion molding:

Process description: Silicone material is extruded into shape through an extruder, commonly used for manufacturing tubular or strip-shaped products. Application: such as silicone tubing, silicone strips, etc. Features: High production efficiency, suitable for continuous production, but the product shape is relatively simple.

Rolling forming:

Process description: The silicone material is rolled into thin sheets or films through a rolling machine. Application: such as silicone film, silicone film, etc. Features: Suitable for manufacturing thin silicone products, but with low production efficiency.

Adhesive molding:

Process description: Wrap silicone material onto other substrates (such as metal or plastic) and shape them through vulcanization. Applications: such as silicone hardware packaging, silicone plastic packaging, etc. Features: Provides additional protection and improves hand feel, but the process is complex and the cost is high.

3D printing:

Process description: Use 3D printing technology to print silicone material layer by layer. Application: Suitable for manufacturing silicone products with complex shapes. Features: High flexibility, suitable for small batch production, but high equipment and material costs.
Differences in craftsmanship

Compression molding: using pre formed silicone blocks. Injection molding: using silicone particles. Extrusion molding: using silicone strips or particles. Rolling forming: using silicone blocks. Encapsulation molding: using liquid silicone gel. 3D printing: using silicone printing materials.

Processing technology of silicone products

Equipment requirements: Compression molding: requires a compression molding machine and mold. Injection molding: requires injection molding machines and molds. Extrusion molding: requires an extruder and mold. Rolling forming: requires rolling machines and molds. Rubber molding: requires a vulcanizing machine and mold. 3D printing: A 3D printer is required.

Production efficiency: Compression molding: Medium, suitable for large-scale production. Injection molding: High, suitable for large-scale production. Extrusion molding: high, suitable for continuous production. Rolling forming: Low, suitable for small batch production.

Adhesive molding: Medium, complex process. 3D printing: Low, suitable for small batch production.

Product complexity: Compression molding: Suitable for simple shapes. Injection molding: suitable for complex shapes. Extrusion molding: suitable for tubular or strip-shaped products. Rolling forming: suitable for thin sheets or films. Encapsulation molding: suitable for complex shapes, providing additional protection. 3D printing: suitable for complex shapes.

Cost considerations: Compression molding: lower cost. Injection molding: The equipment cost is relatively high. Extrusion molding: Medium cost. Rolling forming: Low cost. Encapsulation molding: high cost. 3D printing: Equipment and material costs are relatively high.
Each process has its unique advantages and scope of application, and the choice of process depends on factors such as product design requirements, performance requirements, and production costs. If you need further assistance or have specific questions, please feel free to contact me at any time.

/by

What are the factors that affect liquid silicone molding?

Liquid silicone integrated molding can achieve environmental protection and sustainable development.

There are many influencing factors for liquid silicone integrated molding, from raw material quality, molding temperature, mold structure to environmental temperature, each link may have a profound impact on the final molding effect.

First of all, the composition and properties of silica gel will directly affect the effect of integrated molding. The viscosity, fluidity, curing speed, hardness and other characteristics of silica gel will affect the molding process. High-quality silica gel raw materials usually have good fluidity and toughness, which can ensure that the silicone can be successfully filled in the mold during the molding process, while maintaining good physical properties after the molding. The poor quality of silica gel raw materials may lead to bad phenomena such as fractures and bubbles in the molding process, affecting the molding quality.

Secondly, the molding temperature, humidity and other environmental conditions will also affect the liquid silicone integrated molding. Especially in the curing stage, the control of environmental conditions is crucial to the quality of the molded product. Under normal circumstances, the viscosity of silica gel will decrease with the increase of temperature, and the fluidity will increase. Therefore, it is necessary to reasonably control the molding temperature during the molding process to ensure that the silicone can fully fill the mold and avoid gaps or bubbles. At the same time, too high molding temperature may also lead to silicone aging or burning, affecting the quality of the finished product.

Liquid silicone integrated molding can achieve environmental protection and sustainable development.

In addition, the design and manufacturing quality of the mold is crucial to the liquid silicone integrated molding. The surface finish of the mold, dimensional accuracy, exhaust system design, etc., will affect the quality of the molded product. The design of the mold should take into account the fluidity and molding characteristics of the silicone to ensure that the silicone can be successfully filled to each fine part. Molds with more complex structures may require higher molding temperatures to ensure that the silicone can be filled to every corner. At the same time, the material and surface roughness of the mold will also have an impact on the molding quality.

Finally, the ambient temperature is also a factor that can not be ignored affecting the integrated molding of liquid silicone. In the winter or low temperature environment, the fluidity of silica gel may be reduced, resulting in molding difficulties or adverse phenomena. Therefore, in the production process, the molding temperature and process parameters need to be reasonably adjusted according to the change of environmental temperature to ensure stable molding quality. In addition to the above factors, liquid silicone integrated molding may also be affected by other factors, such as molding pressure, vulcanization time, etc. These factors need to be adjusted and optimized according to the specific production conditions and product requirements to ensure the best quality and performance of the final product.

To sum up, there are many influencing factors of liquid silica gel molding, and it is necessary to comprehensively consider raw material quality, molding temperature, mold structure, environmental temperature and other factors in the production process, and ensure that the final molding effect reaches the best state through reasonable process parameter adjustment and control. Liquid silicone integrated molding using liquid silicone fluidity and formability, simplify product structure, improve production efficiency. This technology can realize the sealing of complex structures, reduce assembly errors, reduce costs, achieve material diversity, environmental protection and sustainability, and is widely used in automotive, electronics, medical and other fields, with broad prospects.

/by