During operation of fully automatic plastic bottle blowing machines, constant temperature control within the workshop is critical for preform heating and blow molding quality. Per production process requirements, the environmental temperature in the bottle blowing workshop should typically be maintained between 20°C–25°C, while the process temperature in the preform heating zone is generally set within the range of 100°C–130°C. Specific temperatures require adjustment based on material type (e.g., PET) and bottle specifications.

I. Key Temperature Control Zones and Setting Standards for Blow Molding Machines

Workshop Ambient Temperature (Temperature-Controlled Clean Zone)

Recommended Temperature: 20°C–25°C
Control Purpose: Maintain stable air conditions to prevent condensation or airflow turbulence caused by temperature differentials, which could compromise cleanliness and equipment precision. Particularly in pharmaceutical and food-grade packaging production, environmental control must comply with ISO Class 7 (Class 10,000) cleanroom standards.

Preform Heating Zone Temperature (Infrared Tunnel)

Common Temperature Range: 100°C–130°C
Zone Control: The heating zone is typically divided into 3–4 temperature control sections. By independently adjusting the power of infrared lamps in each section, gradient heating from the bottom to the neck of the preform is achieved, ensuring uniform material heating.
Temperature Adjustment Criteria:
- Larger bottle capacity requires higher heating temperatures;
- The neck area often requires enhanced heating due to wall thickness;
- When environmental humidity is high, oven temperature should be appropriately increased to compensate for heat loss.

Mold Cooling Temperature

Cooling water temperature is recommended to be maintained between 5°C–10°C to accelerate bottle body setting, enhance production efficiency, and reduce deformation risks.
II. Key Technical Support for Constant Temperature Control
Automatic Temperature Exhaust System: Continuously expels accumulated hot air from the tunnel to prevent localized overheating that causes uneven preform softening.
Adjustable Reflector and Lamp Tube Layout: Adjust lamp height, width, and reflector angle to accommodate heating requirements for different preform structures, improving thermal efficiency;
Microcomputer Control System: Supports temperature curve memory and automatic compensation, enabling rapid parameter recall during product changeovers to ensure process consistency.
III. Workshop Design Considerations for High-Temperature Environments

To ensure long-term stable operation of blow molding machines, workshop construction and layout must meet the following requirements:

Table
Element    Design Standard
Wall and Ceiling Materials
304 stainless steel sheets or high-temperature resistant color steel sheets, with fully sealed joints to prevent dust accumulation and thermal deformation
Floor Treatment
Anti-slip epoxy self-leveling flooring resistant to 100°C thermal shock, featuring a slight slope toward drainage grates
Air Cleanliness
Blow molding zone designed to ISO Class 7 (Class 10,000) standards; critical areas (e.g., neck cooling) require vertical unidirectional flow protection
Compressed Air Cleanliness
Equipped with a three-stage filtration system (water removal, oil removal, bacterial removal), utilizing terminal 0.01μm sterile-grade filters

Actual case study: A pharmaceutical company experienced frequent clogging of downstream filling filters due to airborne fibers entering bottles, resulting in a 30% reduction in overall line efficiency, because the blow molding area lacked laminar flow protection.