Designing Enclosures to Last in Food and Beverage Applications
To properly specify an enclosure designed with features to endure intense washdown environments in food and beverage applications, industrial design engineers must keep a few key factors in mind. In particular, enclosures must be correctly designed and constructed of robust, high-quality components that help keep food product and consumers safe from contaminants throughout operation.
To maintain sanitary conditions, food and beverage environments require high-pressure washdowns and harsh cleaning chemicals to be used on enclosures. If enclosures are not properly protected, these processes can damage electrical controls contained within them. Successful washdowns remove all waste materials and residue from processing systems and controls, preserving product quality and consumer safety.
Even with the appropriate ratings, if electrical and electronic controls are not properly enclosed and protected from undesirable washdown side effects—such as product damage, contamination or corrosion—manufacturers may face significant consequences such as production downtime, food product contamination, and high equipment replacement costs. Attention to detail up front improves longevity in design.
Operating Challenges
Workers in food and beverage environments perform washdown procedures in operating areas once a day, if not more. Certain parts of the operation may also utilize a clean-in-place (CIP) system, which is a contained area that is cleaned on a specified schedule in an automated and highly controlled process. Oftentimes, CIP uses harsher chemicals and higher pressure than other areas of the plant. This category of niche considerations is commonly referred to as sanitary design, often assigned to a specific team member of the facility such as a sanitation engineer. Skipping critical elements of harsh environment controls design within CIP systems can create premature failures of control systems, downtime events or unsafe work environments.
There are three key elements of design that any sanitary environment specifier must consider: the hinge, latch, gasket, and the sanitary elements of all components involved. Each requires unique considerations and design elements to support their success.
Hinge
The hinge provides a secure seal and adds security to the enclosure. Sloped surfaces, lift-off, bullet-style enclosure door hinges are the best choice for washdown environments. These hinges feature a rounded top and smooth finish to allow complete and easy hinge area cleaning, minimizing entrapment of food product and bacteria. These hinges also allow for easy access to the interior of the enclosure, making it simpler to perform maintenance, inspections and modifications. The highest performing hinges are robust, removable and have durable strength in the face of repeated chemical exposure.
Latch
To keep latches clean and ensure washdowns can effectively remove contaminants, sanitary environment specifiers should consider a low profile (flush with the enclosure) or smooth latching design with a minimal number of openings, such as tool-to-open slots. It is equally important to choose a handle that latches securely and forcefully to prevent washdown solution and harsh cleaning chemicals from entering the enclosure. A latch with a tool-free closure is easy and dependable, saving time for workers on the floor.
Gasket
While choosing the optimal enclosure construction and design for washdown is essential, selecting a high-performance seal or gasket is a critical component to ensuring the enclosure’s success. Gaskets and their fixation mechanism or adhesives must be constructed of materials that are compatible with stainless steel, since this is typically the specified enclosure material in these applications. Also, gaskets and adhesives must withstand harsh chemicals during washdowns and be checked periodically for resiliency loss and compression memory. The gasket can be considered the most critical point of design since it protects the enclosures critical automation and control equipment from external elements.
Understanding Enclosures Ratings and Sanitary Design
When it comes to sanitary design, any concave shape or crevice is considered a potential place to harbor bacteria. The core of sanitary design is to utilize materials of construction that are sanitary and can endure harsh chemicals.
4x is a typical rating set by UL that is a majority of all other corrosive environments that our industrial controls operate in. Oftentimes, specifiers will require a type 4x level of equipment protection rating for food and beverage. That is a good start for a low or zero sanitation requirement area, however, this rating overlooks critical elements of sanitary design, including bacteria harboring surface components of an enclosure like crevices, ledges, overhangs or flat-topped surfaces that are seen on common 4x industrial enclosures hinges, latches and gaskets. It is also important to consider designs that minimize or eliminate these surfaces even though 4x does not explicitly call for it. It is also worthwhile to point out that the newly adopted rating of IP69 is not synonymous with sanitary design. IP69 is a high-pressure water ingress protection test procedure that is fully independent of elements of sanitary design. nVent provides a uniquely comprehensive enclosure portfolio to protect critical electrical equipment for all environments.
Our solutions are specially engineered to meet the simplest to most challenging application needs and offer levels of sanitary design and protection for the variety of areas seen in a food and beverage facility. We break it down into high, medium and low levels that closely align to the FDA zones for direct and indirect food contact zones and their respective demands on automation controls.
To learn more about nVent’s complete portfolio of solutions, visit: https://www.nvent.com/en-us/hoffman/food-beverage
