What is the appropriate temperature for blow molded products

The suitable temperature range for blow molded products is generally between 180 ℃ and 220 ℃. Within this temperature range, plastic can fully melt, have good fluidity, facilitate blow molding, and avoid excessive expansion of plastic to produce bubbles, thereby ensuring the compactness and strength of the product. ‌

Temperature requirements for different materials and products

HDPE: The temperature of the blow molding machine is generally set between 170-210 ℃, and the specific temperature parameters need to be adjusted according to the size of the product. Small products have lower temperatures, while large products require higher temperatures. Low temperature can cause embryo rupture, while high temperature can result in uneven wall thickness of the product.

TPV material: The recommended drying temperature before blow molding is 170 ± 10 ℃, and the mold temperature is generally recommended to be below 40 ℃. Lowering the mold temperature helps with product shaping and demolding speed, but may affect the appearance and strength of the product.

The influence of temperature on the quality of blow molding

Low temperature: It can cause the plastic to not melt completely, affecting the quality of blow molding, resulting in surface defects and reduced aesthetics and performance.

High temperature: It can cause excessive melting and expansion of plastic, which can easily form bubbles inside the product, affecting its mechanical properties and durability. In addition, high temperatures may also cause plastic to decompose, producing harmful gases that pose a threat to human health and the environment.

Specific measures for temperature control

Material drying: Before blow molding, ensure that the material is fully dried to avoid air holes or fog spots that may affect the transparency of the final molded product.

Heating temperature of the billet: The heating temperature of the billet needs to be strictly controlled. If it is too high, the viscosity of the molten material will decrease and it is easy to deform. If it is too low, it will accumulate more internal stress inside the product, which is prone to stress cracking during use.