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Linear Motion: A Driving Force in Industry Productivity

Whatever the motion control requirements, linear actuators and leadscrew assemblies play a crucial role in material handling, packaging, and food processing equipment. Conveyor adjustments, lane changers, shrink/stretch wrapping, case erectors, filling machines, labeling, automated ovens, sorting equipment, and other material handling applications all benefit from the use of leadscrew assemblies and linear actuators. They provide clean, quiet, and accurate solutions that are cost-effective. In addition, automation in processing equipment provides quick changeovers on various product sizes, shapes, counts, or container sizes, saving time and reducing costs. Those are critical man-hours that multi-shift staff can never recoup.

Material handling is becoming more complex and integrated into engineered systems as many companies face labor shortages and look to automation to fill the gaps. There is an increasingly high demand for flexible manufacturing capable of handling a wide variety of products. Same-day and next-day shipping have become standard expectations as customers have adopted online shopping trends. Automated warehouses are being set up to increase capacity and productivity and improve working conditions. In warehouse automation, linear actuators and lead screw assemblies are commonly used in grippers, pick and place applications, conveyors, in-process work cells, transporting and storing products. Also, choosing suitable materials for linear motion products in food processing and packing applications is also essential.

As the need for automation becomes increasingly critical, the use of linear actuators and lead screw assemblies will be key factors in driving that success. In addition, this diverse group of products can be configured to accommodate numerous applications and specific design needs that the packaging, material handling, and food processing industries require.

For example, actuators manufactured with stainless steel lead screws and plastic nuts made from food-grade materials can be utilized. These specialty materials can also be compatible in wash-down environments. Acetal with PTFE is often a solution; however, using Ertalyte-TX may be better based on application requirements. Ertalyte-TX provides improved wear resistance, excellent chemical resistivity to standard cleaning solutions, and minimal water absorption. The water absorption rate is three times better than acetal and five times better than nylon based on percentage by weight.

Both standard or anti-backlash plastic nuts are available depending on accuracy and repeatability requirements. These nuts can be supplied as self-lubricating, eliminating the need for additional external lubrication, ensuring the external lubrication won't contaminate the work environment. If extra lubrication is still required, self-lubricating nut materials offer higher wear resistance, lower friction, and higher efficiency. A PTFE coating can also be directly applied to the lead screw.

Also, liner motion solutions and components offer high reliability that lower operating costs. Linear motion products like lead screws, acme screws, and linear actuators decrease production line downtime and improve productivity. Acme lead screws can be combined with manganese bronze nuts to address high static and dynamic load ratings. A significant safety factor is designed into the specs for leadscrew assemblies. Correct selection and sizing of linear motion components can prevent unwanted downtime due to breakdowns and unscheduled maintenance, costing companies unbudgeted money and eroding profits.

Even as an industry shift away from pneumatic cylinders and towards electromechanical actuators has been occurring for the past several years due to the numerous benefits, including reduced noise, lower maintenance, and significant cost savings. Electric Cylinder actuators are an exceptional product for packaging because of the high speeds generated through longer leads on acme screw-driven models. Also, higher loads can be handled by the ball screw-driven electric cylinders. When a combination of high speed and high load is required, an Electric Cylinder actuator with a servo-driven motor and ball screw is an essential option to consider. (See Electric Cylinder article). Electromechanical actuators can offer "intelligent motion" to have current feedback, changes in speeds within the motion cycle, and adjustable stroke lengths to suit products or conditions. An Electric Cylinder can be programmed to move with great speed until it gets close to interacting with fragile products and then slows down as it engages, such as when moving bottles into a shrink wrap process.

Overall, according to The Global News Wire, the food processing, packaging, and material handling industries are expected to grow at a growth rate of 6.1% in the next year. As those industries grow, there will be increasing opportunities for linear actuators and other motion control products to contribute to making that happen. With that, the demand for higher speeds, increased functionality, more throughput, smaller floor space or counter footprint, and reliability are certain. Teaming up with the right linear motion solutions partner that can offer engineering innovation and guidance will help meet those goals.