Dairy processing creates a difficult working environment for many linear motion products. Milk, being a perishable item, must have a controlled process that will quickly fill containers, package, and ship for consumption. Since milk spoils in an open environment, periodic washdown and cleaning of the packaging area is required to ensure no contamination enters the finished product.
For a dairy packaging manufacturer, this daily periodic washdown process resulted in repeated downtime and machine failures on their milk carton caser equipment, causing them to re-examine their linear motion system. The milk carton caser machine initially was operating using linear ball bearings and 440-grade stainless steel shafting to assemble the milk cartons into cases. Over time, the cleaning solvents in the washdown process oxidized the 440-grade stainless steel shafting, causing rust. While the 440-grade series does provide some protection against corrosion, it is partly composed of carbon to make the shafting harder and more durable, which makes it conducive to rust. As the rust issue progressed, the linear bearings would fail and eventually lead to total machine failure for the carton caser.
To reduce machine downtime and preventative maintenance, PBC Linear recommended retrofitting 316 grade stainless steel Simplicity® linear plain bearings as well as 316 grade stainless steel shafting. Simplicity plain bearing technology is self-lubricating, requiring little to no lubrication or maintenance upkeep. This specific bearing solution was equipped with a Frelon® J liner, which is designed for chemical and corrosion resistance. Neither the outer bearing shell nor the 316 stainless steel shafting composition contains carbon. In the washdown environment of the dairy packaging equipment, this resulted in providing extended life for the milk carton caser.
After the Simplicity bearings and stainless steel shafting were installed, our dairy customers were able to eliminate unplanned machine downtime. The manufacturer reported no further problems in the performance of the operation.