Screw trends — better performance, new applications

A number of trends continue to drive developments in screw actuators. For instance, developments in screw materials and manufacturing methods have boosted ball screw performance, leading to greater load densities with higher load capacities. On the design front, more designers/engineers are looking for customized designs, but screw manufacturers are also offering more integrated designs, which can be seen in all-in-one packages such as ball- screw-based linear actuators, which can reduce design time and simplify assembly. And as these new offerings continue, ball screws are being adopted into new applications, such as some medical applications.

One manufacturer of precision ground ball screws, Dynatect, has seen an increased interest in replacing ACME ball screws with precision ground ball screws when refurbishing and upgrading older machining equipment to modern CNC technology/precision. Some of the benefits of upgrading include more precise and repeatable positioning with low backlash and minimal dead-band associated with precision ground ball screws. There’s also increased efficiency using ball screws that can result in smaller sized drive motors.

Plus, more industries are focusing on increasing the uptime of their machine tools. In many cases this includes migrating from run-to-failure on ball screws to a more proactive approach with more frequent changes and saving money by reconditioning used ball screws. This reconditioning approach, complemented by new ball screws, creates a cycle where replacement ball screw inventory can be less expensive.

Dynatect, for one, is seeing more spindle-rebuilders/onsite-machine-rebuilders who previously declined to address ball screws, seeking to partner with the company to repair or refurbish so they can provide a comprehensive portfolio of services to their customers. While Dynatect provides ball screws across a wide size spectrum, it’s the long and large-diameter ball screws that draw unique applications. The company recently manufactured precision ground ball screws that are 67 ft long for precise positioning in a military aerospace application. Wood routing machines, coil winding, and large machining centers have also seen an uptick in demand.

Dynatect has also seen an uptick in many pandemic-related applications. For instance, one perhaps obvious area is medical devices, particularly ones that use slip clutches including blood centrifuge machines, feeding machines, and medication dispensing machines. There’s also increased demand for specialty bellows meeting medical requirements of being anti-microbial and cleanable applied to respirators, diagnostic equipment, and patient beds.

Other applications include package delivery vehicles, which have experienced explosive demand with home delivery increasing. These often use aluminum slatted roll up doors combined with drop-in prepackaged designs. But also, companies are using the pandemic time to invest in automation applications, especially automotive and Tier 1 suppliers. This continues to present strong demand with material handling, robotic applications, palletizing, and end of line processes.

More broadly, Dynatect reports that the coronavirus pandemic has created much larger swings in both demand and capacity. The orders from their customers have become more irregular as they are trying to urgently react to their own uptime/consumption in a dynamic environment. On their end, the company has  more tightly engaged their supply chain with pro-active purchasing to buffer against extended lead times. The intermittent lighter order periods have also freed up their staff to evaluate work flow, machine maintenance, and even expanding the capabilities of certain equipment so they’re better prepared to handle future high/variable demand while minimizing lead-time impact.

Another pandemic-related development is that, recognizing that more customers are working remotely, Dynatect has further invested in their online resources with updated content including significant expansion of video. The company also recently developed an online CAD configurator for their cable carrier offering so that engineers can select and design their own metal or plastic cable carrier. Regardless of what time customers are working, the CAD drawing are downloadable in 22 different formats to immediately drop into their designs.

Along those same lines, Dynatect, like other manufacturers, has increased their investment in product quoting configurators built into their ERP system. These allow their inside sales staff to quote a wider variety of custom products without engineering involvement. Similarly, they’ve invested in an online product/application knowledge database covering 90 major products, with author-users across their engineering, inside- and outside-sales teams.