Stainless steel motors are gaining ground in food and beverage applications
Shrouded electric motors are difficult to clean – fortunately, there is now an alternative.
Equipment in hygiene areas has to be regularly sanitized. And that is when motor shrouds become a real nuisance. They are meant to protect motors on equipment in washdown areas, but they easily get contaminated with food particles. In many cases the motor is fan cooled and acts like a powerful vacuum cleaner, sucking air and airborne contaminants into the shroud, where food particles can build up. There is no easy way to access the motor inside the shroud, and the only way to ensure everything is completely clean is to remove the shroud – a time-consuming operation.
Stainless steel motors are ideal for washdown duty
Stainless steel motors withstand washdown conditions without the need for protective shrouds. These motors are already widely used in North America. In fact, in certain applications in the US food industry stainless steel motors are the only acceptable solution.
Outside North America, machinery suppliers still tend to use regular motors. Unless the food producer specifies stainless steel, regular motors are fitted as they are more affordable. Up to now most food producers outside North America have not specified stainless steel motors, probably because they did not even realize they had a choice.
In Europe there are even machinery suppliers who fit regular motors and shrouds on equipment for their home market but use stainless steel motors in products that are exported to the US. The situation is now starting to change, however. The people who have to operate, maintain and, above all, clean the equipment know only too well that shrouds have no place on machinery that has to be regularly washed down.
Stainless steel motors simply make life much easier for food producers. When you have taken the decision to specify stainless steel motors for your equipment, use the checklist below to ensure you get the best possible motors for your application.
Checklist for selecting stainless steel motors
|1. Designed according to hygienic principles
Stainless steel motors for wet-food processes must be able to withstand harsh washdown conditions and high humidity. Ideally they should be compatible with clean-in-place (CIP) methods to reduce cleaning times. Look for motors with a smooth, self-draining housing with no cavities where food particles could gather.
|2. IP69K ingress protection
The level of ingress protection is important. Many motors advertised as suitable for washdown feature IP66 protection, but IP69K (protected against powerful, high temperature water jets) is clearly superior and essential for providing effective sealing.
|3. No cooling fan
The motor should preferably be a TENV (totally enclosed, non-ventilated) design, which means that it does not have a fan or fan cover – both of which could harbor dirt and are difficult to clean.
|4. Food-grade lubricant
H1 rated lubricants suitable for food environments should be used in the bearings to avoid potential contamination and maximize food safety.
|5. Encapsulated windings
For better reliability the motor should have encapsulated windings. This ensures a longer lifetime in humid conditions and therefore helps to reduce the total cost of ownership.
At ABB we have a lot of experience in supplying stainless steel motors to the food and beverage industry. Our unit in the US, Baldor Electric Company, has been offering NEMA standard washdown motors for more than 20 years. Now we are making the same technology available in Europe and other IEC markets.