Understanding the weight capacity of linear actuators is fundamental for selecting the right component for your project. As a supplier, we know that an incorrect load rating can lead to system failure and safety risks. This article explains the key concepts of static and dynamic load capacities. We aim to provide the foundational knowledge needed to make an informed decision for your application.
Static Load Capacity Limits
The static load capacity, also known as the holding load, is the maximum force a stationary actuator can support without being damaged when it is not in motion. This rating is critical for applications where the actuator must hold a load in a fixed position for extended periods, such as in locking mechanisms or support struts. Exceeding this limit can cause permanent deformation of the screw or housing, leading to premature failure. It is distinct from the dynamic load rating and is often higher. When evaluating an actuator for a static application, it is essential to consult the manufacturer’s specifications for the exact holding capacity. For demanding scenarios, an industrial electric linear actuator might be considered due to its inherent rigidity and ability to handle significant static forces without back-driving.
Dynamic Load Ratings Differ
Dynamic load rating refers to the maximum force an actuator can apply or support while it is extending or retracting. This is the most common rating used for sizing actuators and is directly related to the life expectancy of the internal components, such as the screw and nut. The dynamic load is typically lower than the static load because moving parts experience wear and fatigue. The actual achievable force is also influenced by the actuator’s orientation; a vertical lifting application places different stresses on the motor and gearing than a horizontal push. Manufacturers provide life cycle charts that show the relationship between the applied dynamic load and the expected operational life. In systems requiring high force and precision, an EHA actuator, which combines electric control with hydraulic force, can offer a high dynamic load capacity in a compact form factor.
Force Calculations for Actuators
Calculating the required force for an application is a critical step in selecting the correct actuator. The necessary force is not just the weight of the object but must account for the coefficient of friction for pushing or pulling, the angle of inclination if lifting on a slope, and the desired acceleration. For example, lifting a 100kg weight vertically requires a force of approximately 980 Newtons, but pushing the same weight horizontally on a surface with friction requires a different calculation. It is always recommended to incorporate a safety factor, often between 1.5 and 2, to account for unexpected resistance, shock loads, or variations in the system. Proper force calculation ensures the selected actuator will perform reliably and have a long service life, preventing costly downtime and replacements.
Conclusion
Ultimately, the weight a linear actuator can hold is a precise specification that must be carefully matched to your application’s force requirements, environmental conditions, and safety factors. By understanding the difference between dynamic and static loads and considering all mechanical influences, you can make an informed selection. For projects demanding high force and reliable holding in tough conditions, our engineered solutions are developed to provide that critical performance. We invite you to review the detailed specifications for our systems and contact Rotontek to discuss how we can support your specific load capacity and integration challenges.