An increasing focus on corrosion prevention and contamination exclusion is driving food and beverage companies to reassess equipment specifications and maintenance practices. SKF has developed a comprehensive range of corrosion resistant, safety compliant bearings designed specifically to meet the industry’s evolving needs.
Product safety is the top priority for food and beverage manufacturers, consumers and regulators alike. The latest industry requirements, like the US Food Safety Modernisation Act,ISO 22000 and in New Zealand ”The Food Act 2014” administered by the Ministry for Primary Industries, require companies to place increased emphasis on equipment and processes designed to prevent product contamination during manufacture.
Bearings used in food production machinery present multiple challenges in this context where the wide temperature variations, high humidity and chemically aggressive environments often present in food production can lead to accelerated corrosion and wear. That challenge is compounded by wash-down protocols involving pressurised water jets and chemical cleaning agents. Even maintenance and bearing replacement procedures create a risk of contamination from dropped parts or spilled lubricants.
The foundation of SKF’s offering is the Food Line range of deep groove ball bearings, which feature industry standard stainless steel rings, rolling elements, cages and seal backing plates. For the most demanding environments, the MRC Ultra corrosion resistant range uses proprietary high nitrogen corrosion resistant (HNCR) stainless steel rings and ceramic rolling elements for dramatically improved fatigue life. As standard, the bearings in both ranges are pre-lubricated with grease suitable for incidental contact in food production environments. In accordance with FDA recommendations, the synthetic rubber seals used in the bearings are coloured blue for optical detectability. In addition, the SKF Food Line stainless steel deep groove ball bearing seals have EC approval.
An alternative to conventional grease lubrication is SKF’s Solid Oil technology, a polymer matrix saturated with food grade lubrication oil that keeps contaminants out and resists wash-down chemicals and water without emulsifying. Solid Oil completely fills the internal space within the bearing, encapsulating the cage and rolling elements. The resulting lack of internal voids eliminates ‘breathing’, in which temperature changes between operation and cleaning cycles can allow conventional bearings to draw in moisture, causing corrosion. The Solid Oil matrix also contains two to four times more oil than conventional greased bearings, meaning lubricant life is extended, reducing routine maintenance requirements. This is a particular benefit in hard-to-reach areas.
SKF can use its extensive experience of the food and beverage production environment to develop custom solutions for the most demanding applications. One major ice cream producer, for example, was suffering premature bearing failures in its hardening tunnels as a result of corrosion due to moisture ingress in the bearings. The problem was exacerbated by breathing during cleaning cycles, when bearing temperate rose rapidly from -45°C to +25°C.
SKF replaced the conventional bearings used in the machine’s 32 hubs with MRC HNCR units, lubricated with food grade Solid Oil and further protected by a custom machined, FDA approved optically detectable secondary seal. The new design has extended expected bearing life for the customer from one year to six, and eliminated the need for periodic relubrication with traditional grease, significantly reducing the risk of product contamination and also providing further productivity benefits.
For further information, please contact your local SKF authorised distributor or email customerservice.nz@skf.com
