1. Process Comparison
🔹 Extrusion Blow Molding (EBM)
In extrusion blow molding, melted plastic is extruded into a hollow tube (called a parison). The parison is then clamped inside a mold, and air is blown into it to form the shape of the container.
Main steps:
Plastic melting → Parison extrusion → Mold clamping → Air blowing → Cooling & demolding
Key features:
- Simpler and more flexible process
- Ideal for larger, more complex bottle shapes
- Bottleneck and body formed in one step
- Commonly used with HDPE and other high-flow materials
🔹 Injection Blow Molding (IBM)
In injection blow molding, plastic is first injected into a mold to form a preform. The preform is then transferred to a blow mold, where it is reheated and blown into its final shape.
Main steps:
Preform injection → Cooling & transfer → Air blowing → Cooling & demolding
Key features:
- High neck precision and tight dimensional control
- Excellent surface finish
- Suitable for small-sized, high-precision containers like eye drop bottles and cosmetic jars
- Commonly used with PET, PP, and similar materials
2. Application Scenarios
| Aspect | Extrusion Blow Molding (EBM) | Injection Blow Molding (IBM) |
|---|---|---|
| Suitable Materials | HDPE, LDPE, PP | PET, PP |
| Typical Capacity Range | Medium to large containers (30ml - 7L) | Small containers (5ml - 1L) |
| Common Products | Protein powder jars, shampoo bottles, and household cleaners | Pharmaceutical bottles, essential oil bottles, and cosmetic packaging |
| Mold Cost | Relatively low | Relatively high |
| Neck Precision | Moderate | High |
3. Mingda's Blow Molding Capabilities
As an experienced manufacturer of plastic containers, Hubei Mingda offers both extrusion blow molding and injection blow molding services. We recommend the best-suited process based on product design, material, and usage requirements.
Currently, HDPE products account for 59.99% of our total annual output, mostly made via extrusion blow molding - ideal for large-volume supplement bottles, protein jars, and functional drink containers.
Meanwhile, PET containers, often used for fish oil, liquid calcium, and gummies, are mainly produced through injection blow molding to ensure precise shapes and excellent appearance.