Bearings are a critical part of any manufacturing process and SKF’s expertise and product portfolio offers an easy way to strengthen food safety and process control. Adam McCleery writes.
Food safety has become a much bigger issue over the last 10 to 20 years and as a result the processes used in the food and beverage industry continue to undergo innovation. Swedish bearing and seal manufacturing company, SKF, offer simple and effective solutions for the industry.
“Demand for food has always been there but I think because of things like population growth, the need for food, and more processed and convenience food, the demand with regard to food safety has and continues to increase significantly,” said David Oliver, channel and platform manager bearings and units, SKF.
“As a result, this is a key area of focus in terms of our product development.”
“Beyond that, we must support food producers with Line availability and maintenance costs, the reliability our products provide is also critical in managing the lifetime costs. And last but by no means least, sustainability.”
In terms of sustainability, SKF’s bearing solutions can help to reduce the consumptions of C02, and water.
“All these elements are very important to food producers so any product development we look at for the industry must take those things into consideration,” said Oliver.
“Sustainability in all industries is driving the development of environmentally friendly products, for example, consuming less CO2 or recyclable products.
“SKF can support in improving reliability and by definition improving plant availability, this can significantly reduce lifetime costs, and equally importantly reduce CO2,” said Oliver.
“Bearings sit at the heart of all rotating equipment and there are many critical processes within food and beverage, they have to perform, and they do need lubricant to perform. Because of this one risk is the contamination of the environment from that lubricant and the necessary cleaning of bearings after relubrication.”
It’s estimated that well over 50 per cent of all bearing failures in the food and beverage industry are related to lubrication.
Getting lubrication right is critical and has been the focus of a lot of SKF’s product development, much attention has been applied to relubrication free technologies, whilst still maintaining efficient lubricant performance that can last the life of the bearing.
Relubrication free mitigates the negative impact of relubrication on bearing life and contributes to food safety in and around the bearing.
SKF conducted their own tests with an independent third party to determine the strength of their seal technology and hygienic design.
The third party simulated the cleaning process as it is done in the food and beverage industry, on SKF and competitor products.
“If you are looking at a bearing that isn’t relubricated compared to one that is relubricated, the testing reveals that about a third less water is consumed in cleaning, that water is typically heated which brings in a C02 saving element,” said Oliver.
“If you could look at a common asset, such as conveyors, in processing plants, and you eliminate relubrication then you are talking about a potential third decrease in the use of warm water for cleaning.”
This means that if you can move to a point where you are eliminating a lot of the need to relubricate then you can have a positive impact on sustainability, environmental impact, water consumption and cost of maintenance.
“Much effort is focused on the sealing of the bearing because typically in food and beverage the applications are relatively slow and lightly loaded, the three things that impact grease life are load, speed, beyond that it’s the environment,” said Oliver.
As the food and beverage manufacturing industry is mostly low load and low speed, the determining factors for better bearing life lies with environment.
“If you can seal that environment out or mitigate it in another way, then you have a long grease life which means you don’t have to relubricate to meet the reliability needs of the industry,” said Oliver.
“We optimise every element of the bearing, from the original material right through to the packaging and once that process is fully optimised, then we have maximised the load carrying capacity and toughness of the bearing which delivers excellent reliability.”
All of this is designed to maximise the effectiveness of the bearings in use.
SKF’s Deep Groove Ball Bearing is a prime example of how the company develops and innovates its bearing and sealing technology, particularly as this is likely the most used bearing type in the food and beverage industry.
“The deep groove ball bearing can do a bit of everything, because of the volumes manufactured it is relatively inexpensive, it has low through to high- speed capability and will accommodate moderate radial and axial loads,” said Oliver.
“It can also have other features enabling it to accommodate typical food production environments, graphite cages for high temperatures for example. It’s a simple product that is well understood and will accommodate most of the needs of machinery on a day-to-day basis.”
SKF has a large range of designs, variants, and sizes of deep groove ball bearings, giving flexibility to meet the needs of the client.
The variants include a single row deep groove ball bearing, stainless- steel deep groove ball bearing, double row deep groove ball bearings all with various clearance, cage and lubricant specifications.
Oliver said the food and beverage industry benefits greatly from the use of high-quality deep groove ball bearing.
“It’s a product group that has really been overlooked, we’ve done a huge amount of work on Foodline ball bearing units for conveyor type applications seen widely across food and beverage and with Foodline stainless steel ball bearings,” he added.
“If you look at volume, a standard deep groove ball bearing is the most widely used, it’s important to have a suitable product.”
These factors, and others, were kept in mind when SKF moved to develop a newer and more effective seal and bearing combination.
“We developed our deep groove ball bearing around the basis of food safety,” he added.
“We know we get good performance from our sealed deep groove ball bearings already and have great sealing efficiency, what we didn’t have was the food compliance and food safety.”
To achieve this goal, SKF retained its seal design but changed the material to an FDA and EC approved rubber and added a high performing NSF H1 registered grease.
“The seal material approval is about how much chemical can be leached form the nitrile rubber when it’s in solution, FDA and EC approval is about having nothing dangerous released from the seal material than can then enter the food stream.
“That is now an approved product, Food Safe out of the box.
The sealing is also blue in colour for better optical detection in case any ends up in a food line.”