IN FOCUS
David Oliver Channel and Platform Manager
How clean are your bearings? There’s one thing we expect of the food industry. Faultless hygiene. And rightly so too. But despite the gleaming surfaces we see on the exterior of our processing equipment, it’s the concealed bearings and their housings that often pose major issues.
But ironically, the washdown procedures that we implement to ensure our equipment is squeaky clean cause further issues, with water penetrating the seals, breaking down and emulsifying the grease, resulting in poor reliability and potential contamination. To counteract such problems, SKF have reengineered the standard mounted bearing, designing the most hygienically stable units on the market, reducing risk to the environment and increasing cost-efficiency in the process.
Contamination problems During washdown processes, food residues and bacteria can spread, potentially landing on bearing housings and creeping into gaps – no matter how small. The highpressure sprays can then help waterborne contamination spread even further. Issue 39
The moist environment provides shelter for the breeding of micro-organisms, while progressively accumulating allergens and other contaminants. The subsequent pressure washing flushes them out, but only to other areas. Jet sprays can then lift contamination into the air, producing aerosols, which later settle and infect more surfaces. And that’s just on the outside. The caustics and detergents entering the bearing cavities cause corrosion, and the grease breakdown leads to the requirement of more frequent lubricant replenishment. The relubrication process then purges the old spent grease out of the housing, increasing the potential of contamination with excess grease attaching to cloths and gloves used in the dry-cleaning process.
Six new patent submissions and three design protections
Bearing protection. Patented Underlined with six new patented submissions and three design protections, the SKF Food Line – Blue Range can be the answer to many of these problems. Relubrication-free, each unit is filled with purpose-designed, food-grade, allergen-free grease that is contained safely and protected by effective sealing technology.
A completely new approach to bearing sealing Manufactured from inert, chemical-resistant hydrophobic polypropylene (PP), with long glass fibre for additional strength, they’re designed with hygienic smooth surfaces, purposely shaped for self-draining. And if damaged, the distinctive food-grade blue colour is easy to detect optically. An innovative rubber base seal is injected into the housing and co-moulded to fill the gaps between the structure and machine frame. A stop limiter around the housing bushes allows optimal bolt tightening torque, while maintaining a hygienic seal.
