Silicone products are a relatively common product in our life. Compared with plastic, silicone is more stable and environmentally friendly. It is widely used in mother and child products, such as baby pacifiers, children’s toys, silicone phone cases, watch bands, oxygen masks, etc. So many friends will be curious: how to turn such a soft thing into a shaped object?
Silicone products are divided into A and B rubber. A dosing device controls the ratio of 1:1, then mixed by a static mixer and injected into the injection machine tube for injection molding.
The silicone is injected into the hot sprue mold to make silicone products, achieving the advantages of one-time molding, no waste, and automation.
Due to the low viscosity of silicone, silicone product manufacturers have to consider the backflow and leakage of material during the process, so the sealing of the screw needs to be carefully confirmed.
Silicone processing has a high expansion coefficient, which expands when heated but shrinks slightly when cooled, so the part cannot maintain an accurate side margin in the mold. Therefore, use the cold runner processing, where keep the silicone at a low temperature and flowable. The cold runner is a closed system. The closed system uses a “sealing pin” or “needle valve” in each runner to control the accurate metering of the LSR material during the injection cycle. The closed system uses a “sealing needle” or “needle valve” in each flow channel to control the accurate dosing of LSR material.
The silicone material has good thermal expansion characteristics, with a 2-4% (vulcanization temperature of 150°C), while silicone has the deformation characteristics under pressure. The softness and stability of silicone injection molded products make them ideal for seals and hardware-covered products. Silicone is an environmentally friendly material. Because of its good performance has been favored, accepted, and widely used by various industries to produce various individually shaped products.
Features of LSR injection molding machine
1. The German “2KM” (200L) liquid silicone feeding host is included.
2. Multi-stage precision mold electric heating temperature control.
3. LSR special oil pressure water-cooled closed injection nozzle.
4. LSR particular material tube set.
5. Heat-break cold water board.
6. Heat insulation glass fiberboard.
7. Rotary or double sliding plate design (one upper and two lower molds), more convenient to pick up and put down parts. Moreover, the operator can use the pause time when LSR heat-set molding to do the work of picking up/putting down another mold and cleaning up the mold, which significantly increases the production efficiency.
8. Special feeding and injection design, more accurate feeding, and measuring.
9.Adjustable vacuum device is optional to prevent product air bubbles.