Intelligent upgrade: How does a servo injection molding machine achieve high precision and high efficiency?

1. How does servo drive technology improve the stability of injection molding?

Accurately control power output and reduce fluctuations

Traditional hydraulic presses: rely on a motor with a constant speed to drive the oil pump, and adjust the pressure and flow through valves, which has large energy loss and delayed response.

 

Servo drive: Adopt a closed-loop control system to monitor parameters such as pressure and speed in real time, directly adjust the oil pump speed through the servo motor, dynamically match the actual needs, avoid pressure/flow fluctuations, and ensure the stability of each stage of the injection molding process (injection, pressure holding, cooling).

 

Effect: The product weight error can be controlled within ±0.3%, reducing flash or short shot problems.

Faster response speed and improved repeatability

The servo motor response time is only milliseconds, which is more than 10 times faster than the traditional hydraulic system, and can quickly correct parameter deviations (such as sudden changes in injection speed).

 

Especially suitable for high-precision products (such as electronic connectors and medical components) to avoid batch differences due to delays.

Energy saving and noise reduction, reduce thermal interference

The traditional hydraulic press continuously runs the oil pump, and 80% of the energy is converted into heat energy, which causes the oil temperature to rise, and the viscosity change affects the stability.

Servo technology supplies energy on demand, and the motor is stationary when it stops, reducing oil temperature fluctuations (the temperature difference can be controlled within ±1°C), and avoiding pressure drift caused by oil temperature changes.

Data: The servo machine saves 50%-70% energy and reduces the frequency of hydraulic oil replacement.

Intelligent compensation and adaptive function

Integrated pressure/temperature sensor, real-time feedback data to the control system, automatic compensation for mold wear or material fluidity differences.

Some high-end models have self-learning algorithms, optimize process parameters based on historical data, and maintain stability for a long time.

Application scenarios: respond to seasonal changes in ambient temperature and humidity, or differences in the melt index of different batches of raw materials.

Reduce mechanical wear and extend equipment life

Traditional hydraulic press valves are frequently operated and easily worn, resulting in pressure leakage and performance degradation.

The servo system reduces the frequency of valve use, reduces the loss of moving parts, and extends the maintenance cycle by more than 30%.

 

Summary: How does servo technology "lock" stability?

Precise power: output on demand, no overshoot or lag.

Quick response: millisecond-level correction to ensure repeatability.

Environmentally friendly: temperature control, noise reduction, energy saving, and reduced external interference.

Intelligent adaptation: automatic compensation of variables to reduce the need for human intervention.

2. Servo injection molding machine vs. traditional injection molding machine: the secret of up to 70% energy saving"

1. Fundamental differences in power systems

(1) Traditional hydraulic injection molding machine: "extensive mode" with continuous energy consumption

Working principle: The asynchronous motor drives the oil pump at a constant speed, and the flow and pressure are adjusted by a proportional valve or servo valve. The excess hydraulic oil returns to the oil tank through the overflow valve, causing energy waste.

Energy consumption pain points:

The motor always runs at full speed, even if the injection molding machine is in standby or cooling stage.

The valve control system has pressure loss, and the energy utilization rate is only 30%-40%.

The hydraulic oil temperature rises quickly, requiring an additional cooling system, which further consumes electricity.

 

(2) Servo injection molding machine: "precise mode" with on-demand energy supply

Working principle: The servo motor directly drives the oil pump, and the speed is adjusted in real time according to actual needs, without overflow loss.

Energy-saving core:

Zero consumption in standby: The motor stops when there is no action, and the power consumption approaches 0.

Output on demand: Accurately match the power in the injection, pressure holding, mold opening and other stages to avoid excessive energy waste.

Efficient transmission: The energy utilization rate of the servo system reaches 80%-90%.

Comparison data:

Working conditions	Conventional hydraulic press power consumption	Servo injection molding machine power consumption	Energy saving rate
Injection stage	100%	60%-80%	20%-40%
Pressure holding stage	80%	30%-50%	40%-60%
Cooling/standby	40%-60%	0%-10%	70%-100%

 

 

Three major technical supports for 70% energy saving

(1) Efficient combination of servo motor + variable pump

Traditional hydraulic presses use fixed-flow pumps; servo presses use variable pumps, and the flow rate is dynamically adjusted with the speed, reducing the hydraulic oil circulation loss.

 

(2) Accurate response of closed-loop control

The servo system uses real-time feedback signals from pressure and position sensors to dynamically adjust the motor speed, avoiding the "valve throttling loss" of traditional hydraulic presses.

Effect: Eliminate pressure fluctuations, reduce scrap rate, and indirectly reduce energy consumption.

 

(3) Thermal energy management optimization

Traditional hydraulic presses cause the oil temperature to rise to above 50°C due to overflow and friction, and the cooler needs to work continuously (accounting for 5%-10% of the total power consumption of the machine).

The hydraulic oil temperature of the servo press rises lower (<35°C), reducing cooling energy consumption and extending the oil life.

 

3. How to maintain a servo injection molding machine? Practical tips to extend the life of the equipment

Daily maintenance: basic but critical

• Hydraulic system maintenance

Hydraulic oil management

Regular replacement: every 4000-6000 hours or according to the manufacturer's requirements (traditional machines require 2000 hours), and anti-wear hydraulic oil is preferred.

Oil temperature control: keep the oil temperature between 35-50℃. If it exceeds 55℃, check the cooler or oil circuit blockage.

Pollution prevention and control: install a magnetic filter on the oil tank, clean the oil suction filter regularly to prevent metal chips from entering the pump valve.

Oil circuit inspection

 

Check the pipeline for oil leakage (especially at the joints) every week, and replace the aging seals in time.

If the shutdown exceeds 24 hours, it needs to run at no load for 5 minutes before putting it into production to avoid hydraulic oil solidification and damage to the pump.

 

• Lubrication system maintenance

Guide rails and screws: use lithium-based grease, manually lubricate every 500 hours or add oil through the centralized lubrication system.

Toggle mechanism: check the lubrication points every shift to avoid dry friction causing template deformation.

 

• Cleaning and dust prevention

Electric control cabinet: Use compressed air to clean the dust on the cooling fan and circuit board every month (power off operation) to prevent overheating and malfunction.

Mold area: Clean the residual plastic in time to avoid flash getting stuck in moving parts.

 

In-depth maintenance of key components

• Servo motor and driver

Heat dissipation inspection: Ensure that the motor cooling fan operates normally and the air inlet is unobstructed (ambient temperature <40℃).

Cable protection: Avoid friction between the cable and metal corners to prevent signal interference (shielding layer grounding is intact).

Parameter calibration: Use an oscilloscope to detect the servo system response curve every six months and adjust the PID parameters to the optimal state.

 

• Ball screw and guide rail

Regular inspection: Use a dial indicator to measure the axial movement of the screw (tolerance <0.02mm). If it exceeds the standard, it needs to be pre-tightened or replaced.

Rust prevention: Anti-rust oil can be applied in humid environments to avoid condensation corrosion.

 

• Injection unit

Screw barrel maintenance

Wash with PP or PE before shutdown to avoid residual corrosive materials.

Check the screw wear every 3 months (especially when processing glass fiber materials). If the wear exceeds the tolerance, it needs to be refurbished or replaced.

Check the check valve: disassemble and clean it every 1000 hours to prevent plastic carbonization from causing unstable injection.

 

Fault prevention and intelligent monitoring

Preventive maintenance plan

Develop a periodic table: Prepare a daily/weekly/monthly/yearly maintenance list according to the equipment manual (example):

Cycle	Maintenance content
Daily	Lubrication point inspection, hydraulic oil level confirmation
Weekly	Filter element cleaning, pipeline oil leakage inspection
Monthly	Electric control cabinet dust removal, lead screw accuracy inspection
Yearly	Hydraulic oil replacement, servo parameter calibration

 

Taboos and recommendations for extending service life

Taboo behaviors

Use inferior hydraulic oil or mix different brands of oil.

Run at full load for a long time (80% load or less is recommended).

Ignore alarm prompts and force production.

 

Recommended practices

Spare parts reserve: always have wearing parts (such as seals, filter elements).

Original support: regularly contact the manufacturer for in-depth maintenance (such as servo drive firmware upgrade).

Environmental optimization: maintain workshop temperature at 10-35℃ and humidity at 30%-60%.