What is the air pressure of the bottle blowing machine?

The air pressure range of the blow molding machine is usually between 0.6 MPa to 4MPa The specific values vary depending on equipment type, process requirements and bottle type. The following is a detailed explanation:

1. Basic air pressure range

1. general standard
   The air supply pressure of most blow molding machines requires 0.6 MPa to 0.8MPa Between, this pressure range can meet basic bottle blowing needs, such as bottle wall thickness uniformity, bottle fullness, etc. If the pressure is too low, it may lead to poor bottle forming quality (such as too thin the bottle wall and partially sunken); if the pressure is too high, it may damage pneumatic components or molds.
2. Blow pressure range
   During the actual blowing process, the blowing pressure (the air pressure directly acting on the preform) is usually between 2MPa to 4MPa between. This pressure needs to be dynamically adjusted according to the preform material (such as PET, PE), bottle shape (such as round, square) and size (such as capacity 0.1L to 2.2L). For example:
   • When blowing small capacity bottles (such as 0.1L), the blowing pressure may be close to 2MPa;
   • When blowing large-capacity or shaped bottles (such as 2.2L), the blowing pressure may need to be increased to 4MPa to ensure molding stability.

2. Differences in air pressure between different types of bottle blowing machines

1. Low pressure bottle blowing machine
   Suitable for small or simple bottle sizes, the air source pressure is usually between 0.6 MPa to 0.8MPa During this period, the blowing pressure may be less than 2MPa. Such equipment is mostly used to produce thin-walled, lightweight bottles (such as disposable beverage bottles).
2. Medium pressure bottle blowing machine
   Air source pressure range is 0.8 MPa to 1.2MPa, blowing pressure can reach 2MPa to 3MPa。This type of equipment can handle bottles with medium thickness bottle walls (such as edible oil bottles and wine bottles), taking into account molding quality and production efficiency.
3. High-pressure bottle blowing machine
   Air source pressure may exceed 1.2MPa, blowing pressure can reach 3MPa to 4MPa。This type of equipment is suitable for thick-walled, high-strength bottles (such as pharmaceutical bottles, chemical containers), or scenarios that require special processes (such as multi-layer co-extrusion).

3. The influence of air pressure on the quality of blowing bottles

1. Impact of insufficient stress
   • The bottle cannot be blown fully, and the thickness of the bottle wall is uneven;
   • Forming defects on the mouth or bottom of the bottle (flying edges, collapsing);
   • Reduction in production efficiency (due to multiple blow molding or manual correction).
2. Effects of excessive stress
   • Bottle burst or mold damaged;
   • Energy waste (high pressure causes increased load on the air compressor);
   • Shorter equipment life (increased wear on pneumatic components).

4. Suggestions for air pressure adjustment and optimization

1. dynamic adjustment
   Adjust the blowing pressure in real time according to the preform material, bottle type and production speed. For example:
   • When increasing the temperature of the preform, the blowing pressure can be appropriately reduced (the high temperature makes the preform easier to stretch);
   • When producing large-capacity bottles, it is necessary to gradually increase the blowing pressure (to avoid instantaneous high pressure causing the bottle to break).
2. equipment selection
   • Small production line: Choose a low-pressure bottle blowing machine to reduce energy consumption and costs;
   • Large-scale or high-precision production line: Select medium and high-pressure bottle blowing machines to ensure molding quality and stability.
3. Maintenance and monitoring
   • Regularly check the output pressure of the air compressor, the tightness of the air pipe and the accuracy of the pressure gauge;
   • Install pressure sensors and automatic adjustment devices to achieve accurate control of air pressure.