PET Stretch Blow Molding Machines
PET Stretch Blow Molding Machines: High-Speed, Linear & Large-Capacity Reheat Systems
PET stretch blow molding machines (SBM) produce clear, lightweight rigid plastic containers via a two-step reheat process. Cold injection-molded preforms are fed into infrared heating ovens, thermalized to orientation temperature (90 C to 115 C), biaxially stretched by mechanical rods, and expanded with high-pressure dry compressed air (2.8 to 3.5 MPa) into high-precision aluminum or steel molds.
Two-step linear reheat blow molders offer operational flexibility, lower tooling switching costs, and modular maintenance compared to rotary systems. Linear setups support production capacities ranging from 1,000 bottles per hour (BPH) up to 12,000 BPH for standard neck finishes (28 mm to 38 mm PCO/1881/1810) and container volumes from 50 ml up to 20 liters.
For B2B packaging convertors and beverage bottling lines, equipment evaluation centers on four technical parameters:
Production Output & Cavitation: Output per cavity per hour (typically 1,000 to 1,500 BPH/cavity for linear machines) and cavity pitch stability.
Energy Management: Infrared heating efficiency, oven air circulation, and high-pressure air recovery rates (up to 30 percent reduction in compressor power demand).
Dimensional Consistency: Wall thickness uniformity, base stress-crack resistance under CSD (carbonated soft drink) pressures, and neck verticality.
Mechanical Reliability: Mold clamping force (toggle/hydraulic/servo-driven locking mechanism) to eliminate mold flash under high blowing pressure.
Key Product Features
Servo-Driven Mechanical Motion
Stretching System: Driven by independent servo motors for precise stretching speeds up to 1.8 m/s, ensuring wall-thickness uniformity along the bottle profile.
Mold Clamping Mechanism: High-rigidity mechanical toggle system synchronized with servo control prevents mold opening during 3.5 MPa high-pressure blowing, eliminating visible seam lines.
Precision Thermal Regulation
Infrared Lamp Modules: Short-wave IR heat penetration allows uniform temperature gradient across preform walls up to 4.5 mm thick.
Air-Cooled Neck Protection: Forced-air cooling channels isolate the preform neck finish from radiation, preserving neck tolerances for leak-free capping.
Pneumatic Energy Recovery Integration
Air Recycle System: Dual-stage valve manifold collects exhaust air from high-pressure blowing (3.0 to 3.5 MPa) and redirects it to low-pressure actuation circuits (0.8 to 1.0 MPa) or pre-blowing stages, reducing total compressed air consumption by 15 percent to 30 percent.
Product Types and Configurations
Linear PET stretch blow molding equipment categorizes into three primary structural variants based on automation level, container volume, and neck geometry:
|
Machine Type |
Cavity Range |
Container Volume Range |
Target Production Speed |
Core Application |
|
High-Speed Fully Automatic Linear Series |
2 to 8 Cavities |
50 ml to 2.0 L |
2,400 to 12,000 BPH |
Bottled Water, CSD, Juices, Cosmetics, Personal Care |
|
Large-Gallon / Large-Format Series |
1 to 2 Cavities |
5.0 L to 20.0 L (3 to 5 Gal) |
400 to 1,200 BPH |
Edible Oil, Water Coolers, Chemical Drums |
|
Semi-Automatic Reheat Blow Series |
1 to 4 Cavities |
50 ml to 20.0 L |
600 to 1,600 BPH |
Small Batch, Wide-Mouth Jars, Custom Specialty Packaging |
Structural & Drive Configurations
Electric Servo vs. Pneumatic Drive: Servo-driven stretching and mold toggle mechanisms provide precise positioning within +/- 0.1 mm, consistent stroke times, lower noise levels, and reduced oil contamination risk compared to pneumatic or hydraulic equivalents.
Heating System Architecture: Reheat ovens utilize short-wave infrared lamps with independent multi-zone temperature adjustments (up to 8 vertical zones) and cooling blowers to prevent preform neck deformation during thermalization.
Key Specifications
|
Specification Parameter |
High-Speed Small Bottle Series (2 to 8 Cavity) |
Large-Format Series (1 to 2 Cavity) |
Wide-Mouth Jar Series (2 to 4 Cavity) |
|
Max Container Volume |
2.0 L |
20.0 L |
5.0 L |
|
Max Production Output |
Up to 12,000 BPH |
Up to 1,200 BPH |
Up to 3,000 BPH |
|
Neck Diameter Range |
18 mm to 38 mm |
38 mm to 120 mm |
38 mm to 110 mm |
|
Max Bottle Diameter |
105 mm |
320 mm |
180 mm |
|
Max Bottle Height |
350 mm |
500 mm |
380 mm |
|
Low-Pressure Air Supply |
0.8 to 1.0 MPa |
0.8 to 1.0 MPa |
0.8 to 1.0 MPa |
|
High-Pressure Air Supply |
2.8 to 3.5 MPa |
2.8 to 3.2 MPa |
2.5 to 3.0 MPa |
|
Chilled Water Requirement |
10 C to 12 C, 0.3 to 0.5 MPa |
10 C to 12 C, 0.3 to 0.5 MPa |
10 C to 12 C, 0.3 to 0.5 MPa |
|
Total Power Installation |
22 kW to 75 kW |
18 kW to 45 kW |
25 kW to 55 kW |
When specifying a PET blow molding machine, plant managers and procurement teams evaluate the following technical criteria:
Bottle Geometry & Material Distribution
Carbonated Containers: Require Petaloid base designs capable of withstanding 6.0 bar internal pressure without base clearance loss.
Hot-Fill Packaging (85 C to 92 C): Requires specialized heat-set molds with oil circulation temperature control (up to 120 C) and vacuum-resistant panel design.
Wide-Mouth Containers: Neck sizes above 38 mm require expanded oven pitch and specific preform clamping mandrels.
Air Compressor System Matching
High-pressure blowing accounts for 60 percent to 70 percent of total electrical power consumption. Calculate actual air flow requirements (m3/min) based on bottle volume, target cycle time, and inclusion of air recovery systems before sizing oil-free high-pressure screw compressors or piston boosters.
Mold Changeover Efficiency
Modular quick-change mold structures reduce tooling swap times from 4 hours down to under 45 minutes, minimizing downtime on multi-SKU production lines.
Applications
Linear PET stretch blow molding machines process containers across diverse industries:
Beverage Bottling Lines: Still mineral water, carbonated soft drinks (CSD), isotonic sports drinks, ready-to-drink (RTD) teas, and hot-fill fruit juices.
Edible Oils & Condiments: Square, rectangular, or round PET bottles from 500 ml to 5 Liters with integrated handle inserting mechanisms.
Large Bulk Water Packaging: 3-gallon to 5-gallon reusable or disposable PET/PC water cooler bottles.
Personal Care & Household Chemicals: Detergent bottles, hand soap containers, shampoo bottles, and pharmaceutical packaging requiring tight neck tolerances for pump integration.
Customization and Supply Scope
Machine & Tooling Customization Capabilities
Custom Neck Finishes: Non-standard neck diameters up to 120 mm, flip-top profiles, and snap-on necks.
Integrated Handle Insertion: Automatic insertion mechanisms for external plastic handles on 3L to 5L edible oil or water bottles during the molding cycle.
Heat-Set Molds: Molds equipped with internal heating channels for hot-fill liquid packaging applications.
Standard Scope of Supply
Automatic Preform Elevator and Unscrambler unit.
Reheat Oven Module with multi-zone heating controls.
Linear Stretch Blow Molding Machine Main Frame.
PLC Control Unit with multi-language industrial touchscreen UI.
Pneumatic Valve Manifold and Filtration Unit.
Optional Auxiliary Equipment
High-Pressure Oil-Free Air Compressor (3.0 to 4.0 MPa).
Low-Pressure Screw Air Compressor (0.8 to 1.0 MPa).
Air Dryer, Precision Filters, and Air Storage Tanks.
Industrial Water Chiller (5HP to 30HP).
Multi-Cavity Aluminum (7075-T6) or Stainless Steel Blow Molds.
FAQ
Request a Quote
Request a detailed engineering specification sheet, turnkey line layout plan, or commercial quotation tailored to your production parameters.
Technical Information Required for Engineering Evaluation:
Container Specifications: Bottle drawing/3D CAD file, target volume (ml/L), neck size (mm), and target bottle weight (grams).
Target Capacity: Required output per hour (BPH) or monthly production volume.
Liquid Medium: Product type (still water, CSD, edible oil, hot-fill juice, chemical).