Blow molding is a plastic processing technique that primarily involves heating flat plastic sheets to soften them, then using vacuum to draw them onto a mold surface, and finally cooling and shaping them. It is widely used in industries such as plastic packaging, lighting, advertising, and decoration. Next, Nanjing Chenghui Hardware & Mechanical Factory shares the blow molding process flow.
1. Prepare materials. Understand customer requirements and accept orders. Once the factory receives an order, prepare materials according to the customer's needs, typically including PET and PVC.
2. Confirm Design Drafts. Confirm order details with the client, requesting either a design draft from them or designing one based on their requirements.
3. Ink Printing: After the design artwork is confirmed, the factory will print flat layouts on PET or PVC boards. This process currently features both automatic and semi-automatic printing. Only one color can be printed at a time, and the factory currently accepts orders for up to seven or eight colors. The more colors, the longer the production time and the higher the cost, as each color printing requires cleaning of machinery and equipment as well as additional ink. This process consumes time and ink.
4. Blister Molding. The flat PVC sheets are placed on the equipment for blister forming. An additional note is that molds are required for the production of blisters. Typically, molds are made of copper or aluminum. Copper molds are usually made from plaster and copper. Aluminum molds are made entirely of aluminum throughout the body, which is costly to produce. However, the significant advantage of aluminum molds is their smooth surface, producing sharp and high-quality large pieces.
5. Trim the excess material. After vacuum forming, there is a lot of leftover material around, which is cut off by a robot (previously requiring manual handling), and may involve piercing, etc. After cutting, there might be some burrs left, which need to be manually inspected and smoothed to reduce and sharpen the edges.
