Whether simple or complex, modern machines share a predictable motion known as torque or force and velocity control. An inherent problem exists when these machines encounter an unexpected force, such as a jam or tool breakage, that exceeds the machine components' design limits, potentially damaging the machine and workpiece. Torque limiters play a crucial role in preventing potential failures by executing a controlled decoupling of the unexpected force, thereby maintaining the machine's integrity. This article will cover the benefits of using a torque limiter, selecting and placing a torque limiter, and the types of torque limiters and their applications.
Torque limiters are not limited to a specific type of machinery. Their versatility is a key benefit, making them crucial in designing machines and protecting against damage and costly downtime caused by machine overloads and failures. They function as a 1:1 transmission if the torque is less than a specified value and as a clutch when the torque surpasses the limit. This quick disconnection of the drive from the driven system, typically in milliseconds, removes much of the inertial energy from the drive train. Torque limiters are used in a wide range of applications and are suitable for a variety of industries, including conveyors, assembly lines, packaging machinery, machine tools, textile machinery, woodworking machines, industrial robots, sheet metal processing equipment, wastewater treatment facilities, printing machines, and servo and DC motor drives to name a few. Their role in preventing costly downtime is a significant advantage for any industry.
The most crucial criterion for selecting a torque limiter is the drive torque. This criterion is of utmost importance and is key to the selection process. Torque limiters span a wide range of rated torque — from less than 1 N-m to over 10,000 kN-m. In multi-component mechanisms, the placement of the torque limiter determines which components are protected. The torque limiter can be located at various points along the drive train and set to decouple the driven components from the driving components. For instance, placing a torque limiter between the output of a gearbox and the driven load protects both the gearbox and motor from overload. Alternatively, you could use a lower torque-rated limiter between the gearbox and the motor, which would only protect the motor from damage. Best practices dictate locating the torque limiter to protect the most expensive component of the drive train.
The torque load determines the limiter's size, type, and cost. Ideally, the torque limiter should be selected or adjusted to slip at a high enough torque to avoid unnecessary tripping, such as during initial machine startup, which is typically the point of highest torque under normal operating conditions. It is best to keep the torque limiter operating where the shaft speed is relatively low for extended service life.
Mechanical torque limiters help the machine designer protect the equipment and operator against damage due to overloads. CDWdrives can assist you in selecting the appropriate style and size of torque limiter for your specific application, which will protect your machine against damage at a relatively low cost. Our sales representatives are backed by a team of engineers who are torque limiter specialists. We carry numerous high-quality torque limiters from leading manufacturers adaptable to nearly any industry.
Contact CDWdrives: 586-949-5474 sales@cdwdrives.com