Ballscrew repair from Dynatect: New calculator to decide when to buy (or refurbish)

Alternatives to the increasing lead time for precision ground ballscrews (PGBS) are driving plant managers to reevaluate procurement options.

OEMs often choose to only purchase new precision ground ballscrews (PGBSs) without evaluating repair options. Other choose to maintain no-stock or low-stock of PGBS due to ease of procurement.

But now with lead times of 16 to 20 weeks, both practices merit revisiting … and now a financial tool is available to let engineers evaluate options.

Download the calculator at dynatect.com/resources/ball-screw-scenario-savings-calculator.

Those who have not previously pursued ballscrew repair may be surprised to learn that 30-60% of used PGBS can be refurbished to new condition with an included warranty. Further, the cost of those repairs is typically just 50-60% the cost of new PGBS. For managers with cost reduction initiatives, a 25% net savings across a population of annual PGBS purchases is significant to reconsider.

Further cost savings can be realized with reduced machine downtime. While downtime costs vary, high-volume production situations can spur downtime time adding up to significant costs. With industry lead times running anywhere from 6 to 50 weeks — a strong, immediate strategy to reduce that downtime is by stocking PGBS. Combining these two strategies, a repair program and a stocking strategy, it is possible to reduce downtime by nearly 90%. Whether it be a new or refurbished, having a PGBS on the shelf could save the day.

Dynatect LSI has introduced a savings calculator to evaluate both potential cost savings and reducing downtime. There are 10 inputs to flexibly model  specific company/application such as the number of machine uptime hours in a working day. It also provides guidance on typical ranges for unknown values. The output includes comparison of downtime day reduction, along with total ballscrew cost and emergency downtime cost. The output can be saved and shared with other stakeholders in evaluating different practices to reach different performance metrics. This tool can empower  design engineers to financially justify repair and stocking options.

One key to balancing new PGBS, refurbished PGBS, custom legacy equipment, uptime, and stock is a supplier who can provide the widest range of options. Machine-tool owners often leverage a combination repair, emergency stock, and replenishment. Here, Dynatect can provide all three services. When unique designs, large sizes, or new ballscrews have long lead times, reliable repair can ensure mission-critical production machines get back to operating faster.