MechChem Africa May-June 2024

Navigating the complexities of electric actuators Navigating the complexities of selecting the right electric actuator can be daunting, but understanding key considerations can highlight the path to an optimal solution. This article investigates the pivotal questions that help in making informed choices.

The first question to ask when looking into an electric actuator is whether the drive mechanism should use a belt or ball screw. The choice depends on specific appli cation needs. For precision motion control, ball-screw actuators excel, offering ±0.01

screw actuator, however, may reduce its maximum speed due to construction limitations, including rotational speed and unsupported screw length. Different screw pitches or intermediate supports

may be necessary to maintain performance and avoid resonance. Stepper or servo motor? Choosing between a stepper and an AC servo motor depends on various factors, in cluding specifications, preference and cost.

mm repeatability compared to belt-driven counterparts, which offer ±0.08 mm. In addition, ball-screw designs offer enhanced safety, espe cially in vertical applications, due to their robust mechani cal connection. While ball screw drives may have slow er maximum speeds, their overall positioning time can match or exceed belt-driven alternatives, particularly in shorter stroke applications of up to 800 mm. Moreover, ball-screw actuators are maintenance-free, unlike belt-driven ones that re quire periodic tensioning, especially in high-load scenarios. Increasing the stroke of a ball

Above: SMC´s easy to operate EQ series electric actuator. Below : A slider

with legacy models, ensuring seamless tran sitions and improved functionalities. Whether you need assistance with product selection, application assessments or aftersales support, the SMC team can help overcome motion control challenges. Expert advice proves invaluable, whether in pre-sales or post-sales scenarios, ensur ing optimal performance and customer satisfaction. www.smcza.co.za type SMC LEFS series ball screw actuator. Ball screw designs offer enhanced safety, especially in vertical applications, due to their robust mechanical connection.

Stepper motors offer maximum torque at low speeds, but this torque decreases significantly at higher speeds. On the other hand, AC servo motors provide consistent torque across a wider speed range, making them preferable for applications requiring greater dynamism. Replacement and aftersales support? In aftersales scenarios, working with a supplier committed to developing compat ible replacement options is crucial. New generation products often offer enhanced features while maintaining compatibility

SMC´s LESYH Series step motor actuator.

SMC’s JXCLF step motor controller with a safe torque off (STO) function to protect people and equipment in the event of a collision.

36 ¦ MechChem Africa • May-June 2024