5 REASONS TO AVOID USING AN EMA—AND WHAT TO USE INSTEAD

Electro-Mechanical Actuators (EMAs) are a common choice in industrial automation, but they aren’t always the best choice for many applications. While they offer benefits like precise control and energy savings, they come with various limitations that can lead to reliability issues, downtime challenges, and increased maintenance costs.
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Education, Electro-Mechanical Replacement, Insights

RETHINKING EMAS IN INDUSTRIAL APPLICATIONS

Electro-Mechanical Actuators (EMAs) are a common choice in industrial automation, but they aren’t always the best choice for many applications. While they offer benefits like precise control and energy savings, they come with various limitations that can lead to reliability issues, downtime challenges, and increased maintenance costs. Here are five key reasons to reconsider using EMAs—and why Kyntronics Hybrid  Actuators (SHA) may offer a superior solution.

1. EMAS STRUGGLE WITH SHOCK LOADS AND SIDE LOADING

One of the most common failure modes of EMAs is their exposure to damage from shock loads, side loading and concentrated wear. The mechanical components of EMAs—including screws, gears, nuts and bearings—can be easily damaged, leading to premature wear, costly repairs, and unplanned downtime. In contrast, SHA technology absorbs shock and side loads effectively thanks to its robust integral cylinder design.

2. LIMITED FORCE AND STROKE RANGE

EMAs offer limited cost-effective options for applications that require high force output (above 5,000 Lbs. of force) or long stroke lengths. Their mechanical drive system design is constrained by physical limitations in longer stroke length configurations (over 24 in.) and internal components become very expensive in higher force models. In contrast, Kyntronics SHA design modularity allows for stroke lengths up to 120 in. and force output up to 150,000 Lbs. in a cost effective package making them highly suitable for heavy-duty applications like forming, pressing, lifting and material handling.

3. COMPLEX MECHANICAL SYSTEMS LEAD TO HIGH MAINTENANCE

The metal-to-metal wear of ball screws / roller screws, gears, bearings and other components in EMAs require regular maintenance including lubrication and part replacements to prolong operating life. Over time, this adds to operational costs and increases downtime risk. SHA’s sealed integral cylinder design eliminates most wear-prone components, reducing maintenance and improving reliability.

4.LESS PRECISE FEEDBACK FOR PROCESS CONTROL

EMAs generally rely on the motor encoder to calculate position of the actuator screw. This approach leads to error due to the number of components located between the motor encoder and screw output itself. In addition, as the actuator components wear, error is further introduced into the system. Force measurement in EMAs often rely on motor current as a proxy for applied force.

This approach is subject to error from friction losses in the numerous components located between the motor and the output screw. SHA technology uses a sensor that directly measures position at the rod end. Integrated pressure sensors near the piston measure extend and retract pressure used to determine output force of the rod enabling precise, real-time motion control and feedback for critical applications.

5. EMA REPAIRS ARE EXPENSIVE AND HAVE LONG LEAD TIMES

Anyone who has experienced having a failed EMA repaired is familiar with the surprisingly high cost and long lead time for repairs. The complexity and number of specialized components in EMAs are often the reason for this. The SHA on the other hand has very few wear components at risk of failure. The rod seal is rated for 50,000,000 inches of travel before a replacement is recommended and this PM can be done by personnel in the field.

 

THE SUPERIOR ALTERNATIVE: KYNTRONICS HYBRID SHA TECHNOLOGY

Kyntronics’ Hybrid Actuators (SHA) and Servo Power Units combine the robustness of hydraulics with the precision of electromechanical technology resulting in an actuation solution with superior benefits. With power-on-demand operation, sealed design, customizable stroke lengths, and minimal maintenance, SHA technology provides significant advantages over EMAs in demanding applications.

SHA BENEFITS AT A GLANCE:

  • Provides high force and long stroke configurations cost effectively.
  • Rugged design absorbs shock and resists side loading.
  • Power-on-demand system reduces energy consumption.
  • Sealed system eliminates leaks and frequent maintenance.
  • Integrated sensors provide precise, real-time control and data collection.

 

While Electro-Mechanical Actuators may work well in light-duty applications, their limitations become apparent in high-performance industrial settings. Kyntronics Hybrid SHA technology is purpose-built to overcome these challenges, offering unmatched durability, precision, and reliability.