Comment puis-je vérifier l'exactitude des données de consommation énergétique fournies par le fournisseur pour la machine de moulage par extrusion-soufflage entièrement électrique ?

At our facility in Shantou, we often see customers confused by the vast difference between a machine’s catalog specifications and its actual performance on the factory floor. You want to cut operational costs, but relying on unverified numbers can lead to shocking electricity bills later. It is frustrating to invest in "efficient" technology only to find your margins shrinking due to hidden energy costs.

To verify accuracy, explicitly request the Euromap 46.1 energy efficiency class certification and mandate a live Factory Acceptance Test (FAT) using a calibrated power analyzer. Do not accept nameplate ratings; instead, demand the Specific Energy Consumption (SEC) value in kWh/kg to determine real-world efficiency.

Understanding the true cost of running your equipment is the first step toward profitable production. Here is how we recommend you dig deeper into the data.

How can I calculate the actual cost per bottle based on the machine’s power rating?

When we calculate Return on Investment (ROI) for our clients, we never use the standard kilowatt rating printed on the motor. Doing so creates a false sense of high operational costs that scares off investors. You are worried about profitability, so you need a formula that reflects actual production, not theoretical maximums.
Return on Investment (ROI) ¹

You must calculate the Specific Energy Consumption (SEC) rather than using the machine’s general kW rating. To get the true cost per bottle, multiply your bottle weight (kg) by the SEC (kWh/kg) and your local electricity rate, ensuring the calculation accounts for material throughput efficiency.

To get a number you can bank on, you need to move away from time-based metrics (like "20kW per hour") and move toward mass-based metrics. In extrusion blow molding (EBM), efficiency is defined by how much energy it takes to process a kilogram of plastic. This is known as Specific Energy Consumption (SEC).

At our factory, we encourage clients to look at the process holistically. The formula Bottle Weight (kg) × SEC (kWh/kg) × Electricity Rate ($/kWh) is powerful because it ties energy cost directly to your production output. If a supplier only gives you the "average power consumption," they might be hiding inefficiencies related to the resin type or cycle speed.

Furthermore, different resins behave differently. We have found that processing PCR (Post-Consumer Recycled) material often requires higher torque on the extruder than virgin HDPE. If you calculate your costs based on virgin material data but run PCR, your actual energy bill could be 15% higher.
PCR (Post-Consumer Recycled) ²

Key Data Points for Calculation

You should request a breakdown of energy usage based on the specific resin you intend to use. Here is a comparison of how different metrics can mislead you versus the reality of SEC.

By insisting on SEC data, you shift the conversation from "how big is the motor" to "how efficient is the process."

Should I require a live energy consumption test during the Factory Acceptance Test?

We always prepare our testing bay for skepticism because we know paper reports can be massaged. You are right to be suspicious of data sheets that look too perfect. Without witnessing the test yourself, you risk accepting a machine that only meets efficiency standards under unrealistic, "lab-perfect" conditions.

You should absolutely enforce a "Live Energy Measurement" clause in your FAT protocol using an IEC 62053 compliant power analyzer. This ensures you witness the actual kW draw during both dry cycles and wet production trials, validating the supplier’s promises before the machine leaves the factory.

load factor ³

Writing this requirement into your contract is one of the best leverage points you have. In our experience exporting to Europe and North America, the most successful projects are those where the "acceptance criteria" are black and white.
Site Acceptance Test (SAT) ⁴

Do not settle for a screenshot of a Human Machine Interface (HMI) screen, which can be calibrated incorrectly. Demand that an external, calibrated power analyzer be connected to the main power feed. We recommend testing two distinct scenarios:

1. The Dry Cycle: This measures the kinematic energy—how much power it takes just to move the platens, carriage, and clamp.
2. The Wet Trial: This is the real test. It involves heating the plastic, extruding the parison, and blowing the bottle.

The Importance of "Your" Material

A common trick in the industry is to run tests with easy-flow virgin material to keep amp draw low. However, if your production relies on regrind or stiff HMW-HDPE, the energy consumption will spike. We always ask our clients to ship their specific resin for the FAT.

FAT vs. SAT Protocol

We also suggest tying a portion of your final payment to a Site Acceptance Test (SAT). The environment in our factory in Shantou might differ from yours. Ambient temperature affects how hard the barrel heaters and cabinet cooling fans have to work.

What is the difference between the installed power and the actual running power consumption?

Our engineering team spends a lot of time explaining electrical schematics to facility managers who are shocked by the "Total Installed Power" figure. You might worry that a high installed power rating implies a power-hungry machine, but this is a misunderstanding of how EBM machinery loads function.
IEC 62053 compliant ⁵

Installed power represents the maximum potential load for safety sizing, whereas actual running consumption is typically 30-60% of that figure. To understand real costs, you must ask for the "load factor" or "average absorbed power," which reflects the machine’s energy usage during standard operation.

virgin HDPE ⁶

Think of "Installed Power" as the speedometer on a sports car that goes up to 300 km/h. You will rarely, if ever, drive that fast, but the car needs the capability to handle a sudden burst of speed. Similarly, an EBM machine needs high installed power to handle:

1. Cold Starts: Heating up the barrel from room temperature.
2. Peak Movements: The millisecond surge when the mold clamps shut or the carriage shuttles.

However, once the machine is up to temperature and running a stable cycle, the heaters turn off (insulated by the plastic itself), and the motors only draw power to maintain speed.
moulage par extrusion-soufflage (EBM) ⁷

The Power Profile Graph

Instead of asking for a single number, ask for a Power Profile Graph. When we calibrate our flight controllers and servo systems, we look at the graph to see the difference between "Peak Power" and "Base Load."

• Peak Power: Spikes during parison extrusion or clamping. High peaks might trigger "demand charges" from your utility company.
• Base Load: The energy used during the cooling phase.

The Cooling Phase Trap

In EBM, the cooling time is often the longest part of the cycle. During this time, the machine is essentially waiting. A truly efficient all-electric machine should enter a "Sleep Mode" where servo motors consume near-zero energy. If the baseload remains high during cooling (e.g., fans running full blast, hydraulic pumps idling), you are paying for waste.

Installed vs. Absorbed Comparison

Here is a breakdown of why the numbers differ so much:

Can the supplier provide case studies or data from existing customers with similar setups?

We understand that you want proof, not just promises. It is risky to be the "guinea pig" for a new configuration, so looking at past data is a smart way to mitigate risk. However, you must ensure the data provided is actually comparable to your specific production line and auxiliary setup.
Specific Energy Consumption (SEC) ⁸

Suppliers should provide case studies that include the "hidden" energy loads of auxiliary systems like compressors and chillers. You must verify if the quoted energy data covers the entire system or just the molding unit, as auxiliaries can consume more energy than the machine itself.

Factory Acceptance Test (FAT) ⁹

When we share case studies with prospective clients, we highlight the System-Wide Energy Footprint. In extrusion blow molding, the machine is often not the biggest energy consumer—the compressed air system is.

The Hidden Auxiliary Load

If a supplier shows you a case study where the machine uses very little power, ask: "Does this include the High-Pressure Air Compressor?" Blowing a bottle requires significant air volume.

• Pneumatic Energy Equivalent: You need to calculate the energy cost of compressing the air.
• Chilled Water: Cooling the mold requires chillers. If the machine has a poor mold cooling design, your chiller has to work double-time, driving up your total factory energy bill.

Verifying "Air" Data

Suppliers often quote air consumption based on the bottle volume (e.g., a 1-liter bottle uses 1 liter of air). This is false.

1. Dead Volume: Air fills the hoses and blow pins, not just the bottle.
2. Leaks: "Wet air" volume includes system leaks.
3. Pressure: Higher pressure requires exponentially more energy to compress.

You should verify the air consumption in Nm³/cycle (Normal cubic meters) specifically for the blowing stage.

Euromap 46.1: The Equalizer

To cut through the marketing noise in case studies, ask if the data aligns with Euromap 46.1. This is the industry standard specifically for EBM machines. It separates "machine-related" energy (motors, heating) from the auxiliary systems. If a supplier provides a Euromap Class 10 certification (consuming <0.29 kWh/kg), you have a normalized benchmark that allows you to compare different suppliers "apples to apples," regardless of the auxiliary equipment they used in their specific test.

Conclusion

To ensure accuracy, verify SEC (kWh/kg) via live FAT testing, analyze power profile graphs for baseload efficiency, and account for auxiliary loads like compressed air to understand the total cost of ownership.
Euromap 46.1 energy efficiency ¹⁰

Footnotes

1. Definition of the financial metric used to calculate profitability. ↩︎
   

2. Contextual information on recycled plastics and post-consumer waste. ↩︎
   

3. Explanation of the electrical load factor concept referenced. ↩︎
   

4. Engineering definition of on-site equipment verification procedures. ↩︎
   

5. Official IEC standard specification for electricity metering equipment. ↩︎
   

6. Details on the properties of High-Density Polyethylene plastic. ↩︎
   

7. Comprehensive explanation of the manufacturing process discussed. ↩︎
   

8. Technical overview of the energy efficiency metric used in manufacturing. ↩︎
   

9. Standard definition of the equipment verification process before delivery. ↩︎
   

10. Official source for the Euromap 46.1 industry standard mentioned. ↩︎