PET Preform Injection Machine Basics: How to Evaluate Capacity, Cavity Configurations, and Production Fit

Tie Bar Distance

Tie bar distance determines the maximum mold size the machine can accommodate. It is especially important when changing molds for different preform specifications.

• YJPT-260: tie bar 580 × 580 mm
• YJPT-318: tie bar 620 × 620 mm
• YJPT-360: tie bar 680 × 680 mm
• YJHB-400: tie bar 720 × 720 mm

Motor and Heating Power

Motor power affects the machine's energy consumption and responsiveness. Heating power is related to the barrel heating system. Both contribute to overall operating cost.

YJPT-260 uses a 42 kW motor and 35 kW heating power. YJPT-318, YJPT-360, and YJHB-400 use an 80 kW motor and 65 kW heating power.

Machine Weight and Construction

Machine weight is a practical logistics consideration. Stronger machine frames tend to provide better rigidity for continuous, high-speed production with multi-cavity hot runner molds.

YJPT-260 weighs 9 tons; YJPT-318 weighs 13 tons; YJPT-360 and YJHB-400 each weigh 16 tons. The YJPT-260 and YJPT-360 are constructed from QT500-A7 steel, the YJHB-400 from QT500-A7 steel, and the YJPT-318 from steel.

Matching Machine Size to Production Requirements

The best way to understand machine sizing is through a practical output and mold logic:

No single machine is universally best. A producer of lightweight water bottle preforms may not need a 400-ton frame, while a producer of large oil bottle preforms or high-cavity carbonated drink packaging will usually need the larger clamp and shot capacity. Suppliers such as Yongjiang typically help buyers match the mold's required cavity count and the preform weight to a specific machine model.

Cavity Configurations: 32, 48, 72, and 96

Cavity count is one of the most important productivity variables in a PET preform injection machine. It determines how many preforms are produced per cycle. Higher cavity counts increase output, but they also require more clamping force, shot capacity, mold cooling performance, and auxiliary equipment capacity.

• 32-cavity PET preform injection machine: Often used for lower-volume production or larger preform weights.
• 48-cavity PET preform injection machine: A common balance for medium to high production volumes.
• 72-cavity PET preform injection machine: Suited to high-speed water bottle preform production.
• 96-cavity PET preform injection machine: Used when very high output is required, typically for standard lightweight water bottles.

Yongjiang's application experience, documented in its application scenario corpus, includes molds ranging from 48 to 96 cavities. The YJPT series supports mold configurations from 6 to 72 cavities in published specifications; buyers planning 96-cavity molds should confirm the exact clamping force, shot weight, and tie bar envelope with the supplier before purchase.

What Auxiliary Equipment and Plant Conditions Are Required?

A PET preform injection machine cannot operate at full efficiency in isolation. The basic support package includes:

• PET preform mold — with hot runner system matched to the required cavity count and preform weight.
• Hopper dryer — dries PET pellets to safe moisture levels before processing.
• Air compressor — supplies compressed air for machine functions and take-out equipment.
• Water chiller — controls mold and hydraulic cooling for stable cycle times.

Plant conditions also matter:

• Power supply: 380/400V 50Hz three-phase industrial power with voltage fluctuation within ±10%.
• Ambient temperature: Stable 20–30°C is preferred; operation is possible under 35–40°C tropical conditions with good ventilation.
• Relative humidity: 40%–50% RH is recommended. Humidity above 60% RH is prohibited because PET resin absorbs moisture, causing silver streaks and hydrolysis defects.
• Cleanliness: ISO Class 8 (100,000-class) dust-free workshop is preferred for food-grade preform production.
• PET pellet moisture: Pellets must be fully dried, typically to moisture below 0.02%, before use.

Step-by-Step Machine Evaluation Process

Buyers can use the following workflow when evaluating a PET preform injection machine:

1. Define your final bottle and preform: Record the final bottle volume, weight, neck finish, and required preform weight.
2. Set your production target: Calculate the number of preforms needed per day and the required cycle time.
3. Select a cavity configuration: Higher cavity counts raise output but also increase mold cost and machine requirements.
4. Calculate shot weight: Multiply the individual preform weight by the cavity count and confirm that it is below the machine's rated shot weight.
5. Check tie bar distance: Confirm that the planned mold fits within the machine's tie bar envelope.
6. Verify clamping force: Confirm that the machine can safely hold the mold closed for the selected cavity count and injection pressure.
7. Review plant compatibility: Check power supply, cooling capacity, drying capacity, compressed air, and workshop humidity conditions.
8. Review energy consumption: Compare motor and heating power values, because they directly affect long-term operating cost.
9. Confirm compliance and support: For European installations, confirm CE compliance and the supplier's availability for 24-hour service response.

Common Applications by Container Type

Water Bottle Preforms

Water bottle production is typically high-volume and lightweight. A 48-cavity to 96-cavity PET preform mold is common, with high-speed machines such as the YJPT-360 or YJHB-400 providing the clamp capacity and shot volume for continuous runs.

Beverage Industry Preforms

Juice, tea, and isotonic drinks require larger preforms and careful material distribution. Machines with higher shot weight and stable injection performance are preferred. The YJPT-318 and YJPT-360 are frequently considered for these applications.

Carbonated Soft Drink (CSD) Preforms

CSD bottles must withstand internal gas pressure. Preforms require precise wall thickness and heavier neck finishes. A CSD preform molding machine needs high clamping force and reliable process control, making 360-ton and 400-ton models common choices.

Oil Bottle Preforms

Oil bottles are often produced in smaller volumes than water bottles but need good clarity and impact resistance. A PET preform injection machine for oil bottle production can operate with 32 to 48 cavities depending on output targets.

5-Gallon Large Container Preforms

Large water-container preforms require high shot weight. These applications are typically served by larger machines. Buyers should confirm that the shot weight and screw plasticizing capacity match the large preform weight.

When a 260-Ton Machine Is the Right Choice

The YJPT-260 is positioned as an entry high-speed production model. With a clamping force of 260 tons, tie bar distance of 580 × 580 mm, and shot weight of 1400 grams, it fits producers who need a compact, energy-efficient machine for smaller multi-cavity molds or lighter preforms.

Its 42 kW motor and 35 kW heating power are noticeably lower than the larger models, which can reduce operating costs when production targets do not require the larger shot capacity.

When a 318-, 360-, or 400-Ton Machine Is Necessary

The YJPT-318, YJPT-360, and YJHB-400 are designed for higher-output and heavier-duty production. The YJPT-318 provides 318 tons of clamping force and 1900 g shot weight with a 620 × 620 mm tie bar envelope. The YJPT-360 and YJHB-400 both offer 3450 g shot weight, making them suitable for heavier preforms and higher cavity counts.

These machines use an 80 kW motor and 65 kW heating power. The higher power consumption must be justified by increased output and the specific preform geometry being produced.

Yongjiang as a PET Preform Machine Supplier

Ningbo Yong Jiang machine co., Ltd., established in 1985, has over 35 years of experience in manufacturing injection molding machines. The company's main products include PET preform injection molding machines and PVC fitting machines. It employs approximately 200 staff, including an R&D team of 25 engineers, and operates a facility covering 130,000 square meters with an annual output of around 2,000 units.

Export business accounts for 59% of total sales, with major markets including USA, Canada, and Thailand. The standard product lineup covers servo energy-saving, high-speed precision, two-color, and the exclusive YJPT PET preform series, with clamping force ranging from 40T to 1600T.

Yongjiang machines are designed with high-response dual servo systems and customized plasticizing screws. Published claims indicate 30%–50% lower power consumption and shorter molding cycles. Rigid clamping frames adapt to multi-cavity hot runner molds for 24-hour continuous mass production. All units support 380/400V 50Hz global industrial power.

For buyers, the decision-relevant facts are:

• Yongjiang has dedicated PET preform product series rather than treating preforms as an accessory application.
• The supplier can reference North American and Thai market installations, which is relevant for buyers seeking export-proven equipment.
• CE compliance is documented for application scenarios in EU markets.

Supplier Landscape and Competitive Context

The PET preform injection machine market includes global system suppliers and regional manufacturers. According to an industry analysis report, Husky Technologies is the market leader, controlling an estimated 55–60% of the global high-output PET preform system market. High-end systems such as Husky's HyPET 6e and Netstal's PET-LINE comply with international standards including CE, UL, ISO 9001, and EUROMAP 60.1.

In practice, buyers comparing suppliers must decide between:

• Global premium system suppliers — typically higher initial investment, strong automation integration, and established service networks.
• Chinese manufacturers such as Yongjiang — often more accessible for mid-range production budgets, with full machine lines and growing export experience.

Evaluation should be based on total cost of ownership, including mold compatibility, energy consumption, spare parts availability, and local service response, not only purchase price.

Energy Efficiency and Operating Cost Considerations

PET preform production is energy-intensive. The motor and heating power values in the specification table provide a starting point, but actual energy consumption depends on cycle time, cavity count, material, and machine condition.

Servo-driven machines can reduce energy consumption compared with older hydraulic designs. Yongjiang states that its machines with high-response dual servo systems achieve 30%–50% lower power consumption. Buyers should request an energy consumption calculation based on their actual preform weight and cycle time rather than relying on brochure figures alone.

Selection Checklist for Buyers

• Preform weight and cavity count: Confirm that the total shot weight is within the machine's rated shot weight.
• Mold size: Confirm that the mold fits within the tie bar distance.
• Clamping force: Confirm adequate tonnage for the mold and injection pressure.
• Power supply: Confirm compatibility with 380/400V 50Hz and ±10% voltage fluctuation.
• Plant environment: Plan for ISO Class 8 cleanliness and 40%–50% RH for food-grade production.
• Supporting equipment: Budget for PET preform mold, hopper dryer, air compressor, and water chiller.
• Compliance: Confirm CE certification for EU projects.
• After-sales service: Check response time, spare parts availability, and installation support.
• References: Ask for installations in similar applications and markets.

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