Metal Belts vs Plastic Belts: Which is Better for Food Conveying Applications?
Plastic and metal conveying belts are both great choices for the Food Processing Industry, but for very different reasons. What makes one belt perfect for one application might make it a poor choice for another. When selecting a food conveying system for your application, choosing between plastic and metal conveyor belting is one of the most important factors in ensuring that your operation is safe and sustainable.
In applications that deal with food products, running a sanitary operation is critical. While plastic belts may be easy to clean, they are also susceptible to more scratches and cracks than metal belts. Any surface perforations open up space for germs and pathogens to hide, making the belt not suitable for use in certain food applications. Metal belts are very durable, and often times can be the more sanitary choice.
Not to be confused with sanitation, the ability to easily clean a belt is critical to the success of any food application. Both metal and plastic belts have their own benefits when it comes to cleaning. Metal belts prevent scratches where pathogens can hide and are also capable of being cleaned in place, but can be prone to contaminant buildup over time. Under a microscope, plastic belts can have a very smooth finish that limits biofilm adhesion. However, as mentioned earlier, polymer belts are prone to scratching. It is important to conduct regular cleaning as required for you operation, but the type of belt you utilize can help keep buildup in between cleanings to a minimum.
Metal belts offer a greater percent of open area, which can be beneficial in coating applications, cooking, baking, or any application where drainage is important. Metal belting can also accommodate smaller products with tighter mesh openings allowing for a wide range of applications. Plastic on the other hand can create a virtually solid and flat surface which is excellent for very small products, or for creating a smooth and flat conveying surface. Additionally, plastic can offer a variety of surface treatments that aid with the conveyance of the product. Nub top, grip top, and slotted configurations are all possible. Because both metal and plastic can accommodate a variety of opening configurations, the nature of the application itself allows for the best belt to be used on the application.
Conveyor belts used in food applications are required to withstand extremely harsh environments such as ovens and freezers. The change in high and low temperatures that some operations require make plastic belts ineffective. Metal can handle the change in temperatures, making them perfect for applications in bakery and snack food operations.
Friction & Impact Loading
For applications where friction between the product and the belting needs to be at a minimum, plastic belts hold the advantage. Plastic belts reduce friction and wear, which can help in areas that rub up against metal components and in applications where product accumulation is needed. Plastic belts can also absorb more impact load without deforming over time, unlike metal belts. In an operation where the risk of impact is higher, using plastic belting will increase the service life of your processing application.
Unlike in the case of extreme temperatures, both metal and plastic belts are extremely chemical resistant. Polymer based plastic belts and high-grade, stainless steel belts are designed to withstand harsh chemical environments without any issue.
Repair & Maintenance
Plastic belts offer ease of maintenance advantages in many situations over metal belting. They are modular in design and lighter in weight, making them easy to perform routine maintenance.
For operations with tight turn radiuses and spiral layouts, flexibility is key. It might seem logical that plastic belts are designed to handle much tighter turns than metal belts, but that isn’t always the case. The adaptability that a plastic belt offers gives the end user more freedom in designing the conveying operation to meet specific design needs. Similarly, metal belts can navigate down to a ¼” diameter nosebar. Both metal and plastic belts are great for tight turn operations, but as for which type is right for you, it truly depends on the application.
One of the biggest differences between metal and plastic belts is that metal is an easily detectable material. In the food processing industry, it is crucial to be able to tell if and when a foreign object has contaminated the food. If a piece of metal belting were to break off, it would be much easier to detect than if the same occurred to a plastic belt.
Which is better for you?
The benefits of both types of belt are apparent. At the end of the day it all depends on what application the belt is needed for. A belt that we would suggest for baking, freezing and battering applications might not be the same as a belt we would suggest for icing, frying and cooling applications. Having a good relationship with your belt supplier is one of the most beneficial things you can do when choosing conveying solutions for your operation. Having open lines of communications and trusting that your supplier understands your needs, and can suggest the best product for your application – regardless of metal or plastic - will help prevent unplanned downtime in the future by ensuring the belt you choose will be a safe and sustainable option for your operation.
For the best in Metal and Plastic belting, contact us at 1-866-Rexnord (1-866-739-6673), or contact us.