Thinking about modernizing your legacy hydraulic systems? Servo motor conversion kits offer a path to enhanced efficiency and control. Our guide explores how these kits can breathe new life into your existing equipment. This is a guide.
Hydraulic systems have long been the workhorses of industrial applications, providing the muscle needed for heavy lifting and precise movements. However, traditional hydraulic systems, often relying on standard motors and constant pumps, can be energy inefficient and noisy. Servo-hydraulic systems, on the other hand, offer a more efficient and controllable alternative. Retrofitting existing hydraulic systems with servo motors can breathe new life into legacy equipment, enhancing performance and reducing operational costs. This article explores the benefits of hydraulic to servo motor conversion kits and provides a practical guide to the process.
Why Consider a Servo Motor Retrofit?
Switching from conventional hydraulic systems with standard motors to servo-hydraulics is particularly beneficial when equipment operates with frequent start/stops， includes many pause times or partial load ranges， or during prolonged periods where no hydraulic power is required. Retrofit solutions can significantly improve the energy efficiency of existing machines. The advantages of servo-hydraulics become apparent over the entire service life of the machine.
Here’s a breakdown of the advantages:
- Improved Energy Efficiency: Servo motors only draw power when needed, eliminating the energy waste associated with continuously running standard motors in traditional hydraulic systems.
- Enhanced Control: Servo motors provide precise speed and position control, leading to improved accuracy and repeatability in machine operations.
- Reduced Noise Levels: Servo-hydraulic systems operate much quieter than conventional hydraulic systems due to the on-demand nature of the servo motor.
- Lower Maintenance Costs: With reduced wear and tear on components and the elimination of continuous operation, maintenance requirements are typically lower for servo-hydraulic systems.
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Increased Productivity: The faster cycle times and improved control offered by servo motors can lead to increased production output.
Comparison of Hydraulic SystemsFeature Standard Motor with Constant Pump Standard Motor with Variable Pump Servo Motor with Constant Pump Energy Efficiency Low Medium High Control Accuracy Low Medium High Noise Level High High Low Maintenance Costs High Medium Low Initial Cost Low Medium High Understanding Servo-Hydraulic Systems
A servo-hydraulic system replaces uncontrolled standard motors with precisely controllable servo motors. The core components of a servo-hydraulic system include:
- Servo Motor: A precisely controllable electric motor that drives the hydraulic pump.
- Constant Pump: A hydraulic pump that delivers a constant flow of fluid when driven by the servo motor.
- Servo Drive (Converter): An electronic device that controls the speed and torque of the servo motor based on commands from the machine’s control unit.
- Control Unit: A central processing unit that coordinates the operation of the entire machine, including the servo-hydraulic system.
The Retrofit Process: What to Consider
Retrofitting a traditional hydraulic system with a servo motor conversion kit involves several key considerations:
- System Architecture: Determining the optimal arrangement of components, including the servo motor, pump, and drive, is crucial for achieving desired performance.
- Hardware Selection: Choosing the right components is essential for a successful retrofit.
- Pump: Constant pumps designed for variable-speed operation, smaller in size due to decoupling from the mains, and supports a higher speed.
- Servo Motor: Permanent magnet synchronous motors offering good dynamics, overload capacity, and speed range (up to 6,000 rpm are available). Options include oil-cooled motors for higher power density.
- Servo Drive (Converter): Key component containing software for pressure and flow rate control. Must offer interfaces for integration with the machine’s control unit and pressure sensors. Oil cooling options enhance performance.
- Integration with Existing Control System: Retrofit kits should seamlessly integrate with the machine’s existing control system, minimizing disruption and allowing for continued use of familiar interfaces.
- Software and Commissioning: The servo drive’s software is critical for maximizing the benefits of servo hydraulics. Guided commissioning tools and expert support can simplify the setup process.
- Service and Support: Choosing a system provider that offers comprehensive design, commissioning, and ongoing support is essential for long-term success.
Hardware Considerations In Detail
The Pump: Constant pumps are preferred in servo-hydraulic setups. Many manufacturers offer series tailored for variable-speed operation and high acceleration. Compared to uncontrolled systems, these pumps can be smaller due to decoupling from the power grid, enabling higher speeds and compact dimensions. The pump and motor connection offers options like conventional coupling and pump support, direct attachment via internal toothing, and performance lines with hydraulic fluid used for lubrication.
The Motor: Permanent magnet synchronous motors provide the power. Key selection criteria include dynamic performance, overload capacity, and speed range (up to 6,000 RPM). Options include liquid-cooled motors with higher power density than air-cooled models, and oil-cooled servo motors in sizes 45 to 132 are available.
The Converter: The converter is the biggest difference. A servo drive contains the software for pressure and flow rate control, and many other functions. When switching, the requirements for the central control unit do not change, and system designers can work with their own control types. Ideally, the electronics also have oil cooling.
The ROI of Servo Motor Retrofits
While the initial investment in a servo motor conversion kit may be higher than maintaining a traditional hydraulic system, the long-term return on investment (ROI) can be substantial. The increased energy efficiency, reduced maintenance costs, and improved productivity offered by servo-hydraulic systems often lead to a payback period of one year or less.
Scenarios Where Servo Hydraulics Shine
- Processes with high power requirement fluctuations.
- Cycle with extended pauses.
- Application require reduce the noise level.
Real-World Applications
- Injection Molding Machines: Servo-hydraulics enable precise control of the injection process, resulting in improved part quality and reduced cycle times. During cooling, the servo motor stops, eliminating energy waste.
- Presses: Servo-hydraulic presses offer faster cycle times and improved control over the forming process. They can significantly reduce energy consumption.
- Metal Forming: Retrofitting mechanical presses with servo drives allows the press to open and close faster while maintaining speed for pressing. The servomotor accelerates the slide to TDC. Before impact, servo synchronizes with the flywheel speed.
The Software Side
All functionalities of the servo-hydraulic system is integrated directly in the servo converter. A graphical user interface is used for commissioning and parameterization of the converter through guided commissioning, which makes it possible to commission the system quickly. The latest software includes numerous protection and monitoring functions that further enhance the performance and reliability of the system.
Conclusion
Retrofitting legacy hydraulic systems with servo motor conversion kits offers a compelling pathway to improved energy efficiency, enhanced control, and reduced operational costs. While careful planning and component selection are essential, the potential benefits of a servo-hydraulic conversion make it a worthwhile investment for manufacturers looking to modernize their equipment and optimize their operations.
