Analysis of the Thermoforming Process for Thick-Plate Refrigerators

　　Refrigerator Thick-sheet thermoforming Process analysis: In summer, the refrigerator is an indispensable appliance for freezing and preserving food. With economic growth, demand for refrigerators continues to rise, leading to an increase in supply. Among the components, the refrigerator inner liner—being a critical part—requires particularly careful manufacturing. So, what does the thermoforming process for refrigerator inner liners entail during production?

　　As a thick‑sheet thermoforming process, molds are indispensable. For refrigerator inner liners with blistered surfaces, the appropriate mold is selected based on mass‑production data. Typically, two types of molds are commonly used: wooden molds or aluminum molds.

　　1. Wooden mold

　　Creating a wooden mold has a very short production cycle—typically just one to two days—and the process is similar to vacuum‑forming prototyping, resulting in relatively low costs. However, when using a wooden mold for vacuum forming, the surface of the finished part tends to be rather rough and lacks fine detail. Additionally, wooden molds cannot meet the forming requirements of products with significant depth or thick material.

　　2. Aluminum formwork

　　Aluminum molds are manufactured using electronic control. The mold’s geometry is first designed on a computer based on the engineering drawings, then machined on a CNC milling machine. The production cycle is moderate. Once an aluminum mold is produced, no further post‑processing is required—drilling operations are performed during CNC machining. These molds are highly durable and deliver excellent dimensional accuracy for thermoformed parts; however, their main drawback is the high cost. Thick‑sheet thermoforming.

　　For thermoformed refrigerator liners, when the batch size is sufficiently large, we typically recommend using aluminum molds. The advantages of aluminum molds are clear: ① high precision with minimal tolerances—typically within 0.1 mm; ② a smooth surface that allows for internal plating, resulting in a uniformly smooth, blemish-free finish; ③ exceptional durability and a long service life, making them ideal for high-volume production; ④ uniform heat distribution and sharp edges.

　　These advantages ensure that our thermoformed refrigerator liners boast an attractive appearance and superior quality. Thick‑sheet thermoforming.

　　Once the mold is completed, the next step is plastic molding.

　　Refrigerator Thick-sheet thermoforming Forming is a type of vacuum forming. It involves securing a thermoplastic sheet or film—such as ABS or HIPS—and heating it by radiant heating. The center of the plastic is blown into a hollow bubble, after which a mold is inserted into the plastic bubble. A vacuum pump then evacuates the air between the sheet and the mold, allowing atmospheric pressure to shape the sheet. The part is formed by adhering to the mold; following cooling and holding pressure, compressed air is blown in to release the molded piece from the cavity.

　　Of course, blistering doesn’t always go smoothly; occasionally, issues such as deformation, insufficient blistering, excessive thinning after thermoforming, scratches and streaks, and uneven wall thickness may arise.