Fragile materials are common in food processing. They are sensitive to pressure, temperature, changes in humidity, relative motion, and more. Fragile materials include breakfast cereal, starch-based products (bread doughs), dried fruit, frozen meat patties, chilled or smoked fish fillets, noodles made from various starches, etc.
The conveyor system you choose for fragile materials impacts the quality of your final product. The more damage is done to the material, the lower the quality of the end product is. Your business reputation and sales are directly dependent on material integrity in your production processes.
This blog post will discuss how fragile materials work, what kind of conveyors are available for these products, and how you should choose the right system based on your needs.
Two primary causes of material damage during conveying include relative motion and free fall.
Free fall occurs when the product falls from a height or slides down an incline, and relative motion takes place when two objects are moving with respect to each other. Fragile materials should not be exposed to either of these movements for long periods of time as they can lead to breakage.
It is best practice to put fragile material on conveyors that move slowly, without any sudden jerks or changes in direction.
If a brittle material is being conveyed, it should be put on an incline during the process to limit exposure to the relative motion of other objects and keep any breakage from occurring.
In daily operations, material breakage happens due to lack of attention, rough handling, insufficient storage space, employees not qualified enough, and, most of all, inadequate conveyor systems.
Food processors typically face the following problems with fragile materials:
- Material spoilage
- Material loss
- Downtime and material replacement costs
- A poor reputation for product quality
Damaged products have less value. A damaged particle can also become a breeding ground for microorganisms and therefore lead to fast material spoilage.
To avoid all of these problems, the most critical step is to choose a conveyor system that will handle delicate materials with care.
Definition of Fragile Materials
Fragile materials are foods that can easily be crushed, broken, or otherwise damaged when mishandled. These include coffee beans, ground coffee, breakfast cereal, nuts, and similar.
Nuts such as walnuts, pecans, pistachios, almonds, etc., are fragile because they are perishable. They have a high value and must be stored in the best conditions possible to prevent material loss, spoilage, or damage.
The storage temperature should never exceed 45 degrees Fahrenheit as this will cause nuts to become stale – meaning they lose their flavor and texture over time (become dried out). The humidity level also should not exceed 70% to prevent molding and discoloration. Nuts are brittle, meaning they are sensitive to motion and free fall in particular.
Similarly, breakfast cereals should be handled gently during transport to avoid breaking or crumbling. Cereals typically consist of nuts, grains, dried fruit, and other ingredients mixed. These are sensitive to heat, humidity, and vibrations.
Coffee beans have little moisture content, making them brittle and sensitive to shock, vibration, or changes in humidity. Ground coffee is also considered a fragile material because of its fine texture. Powder materials require special consideration because they can become airborne and are susceptible to windage and static electricity.
Frozen fruits and vegetables are also fragile due to their moisture content.
All of these types of foods and food materials require special considerations in terms of transport and handling.
Best Conveyors for Fragile Materials
Here are the four most common types of conveyors used for fragile materials in food processing.
Tubular Drag Cable Conveyors
Arguably the best choice for this type of conveying, tubular drag cable systems are enclosed, modular (and highly flexible), and easy to clean and maintain. They are ideal for conveying the following material:
- Nuts (almonds, peanuts, pecans, pistachios, and walnuts)
- Coffee (green coffee beans, roasted coffee beans, ground coffee)
- Dried peas
- Dried beans
- Frozen fruits and vegetables
- Breakfast cereals
The mechanism of a tubular cable conveyor is based on an enclosed tube with a sealed stainless steel cable running through it. Circular discs are evenly spaced along this cable to create “pockets” for gentle material conveying.
The enclosed nature of the conveyor protects the product from dust, dirt, and external factors.
Aside from being the prime choice for more delicate materials, tubular cable conveyors also come with the following benefits:
- Reduced noise
- Modular design (for any floor layout)
- No food contamination
- Low maintenance and cleaning costs
- Low energy expenditure
- Non-existent material loss
- Preserved product shape and quality
The main concept of a wrap conveyor is that it starts as an open belt system. It then wraps itself into a tube that can be used to convey the product. This tube is supported by guard rails all along the conveyor. The end result is that the belt wraps around on itself and then opens again.
Wrap (or tube) conveyors work on inclines as well as curvatures. They can accommodate multiple inlets and outlets and are relatively easy to clean.
They are a good option for these materials:
- Fish food
- Fish and shellfish
- Animal and pet food
Unfortunately, wrap conveyors have a lower transport capacity per unit length of belt compared to open belt conveyors. They also may not be as flexible as tubular cable conveyors.
Vibratory conveyors utilize vibrational energy to move materials along a smooth trough. This trough comes with attached vibratory components that make it shake lengthwise. The material particles then “hop” with the vibration frequency in the desired direction towards one end of the trough.
Even though they vibrate, these conveying systems cause low material degradation and efficiently operate at high temperatures.
However, they are better suited for larger particles than fine powders. Cohesive materials also have the potential of sticking to the conveyor and being discharged in agglomerated lumps.
Another significant downside to vibratory conveyors is that they cannot operate over long distances. They are also unsuitable for high inclines. If you have a lot of space to cover and need a powerful conveyor, vibratory systems are not the ideal choice.
Even though they are more closely associated with the mining and manufacturing industries, belt conveyors represent a solid option for moving fragile materials in the food processing industry. During transport, the conveyed material remains stationary on the belt, meaning it does not move at all – a perfect scenario for fragile food materials.
Belt conveyors come in the form of open and closed ones. Open conveyors are not a suitable choice for the food processing industry, as they expose the conveyed material to the environment, which can lead to contamination and material loss.
Closed belt conveyors are easy and inexpensive to install in new buildings or retrofitted into existing ones without expensive alterations. They protect materials from outside exposure.
However, belt conveyors have a limited conveying angle. This can be improved with a texture belt, but it still cannot function well in tight spaces that require sharp turns or plenty of low-to-high elevation changes.
Additionally, despite meeting most of the requirements, enclosed belt conveyors can be difficult to clean. Food material can get caught within the enclosure and become a source of contamination.
Even though we’ve outlined the most suitable conveying systems for different types of fragile materials, these are not the only factors you should consider when making your final selection.
On the contrary, there are quite a few other things to keep in mind, such as the size of your facility and production line layout. When designing a conveyor system for fragile materials-specific needs, you should also consider other types of product flow, like gravity-based systems or roller conveyors for items that are not particularly sensitive to rough handling.
Your decision-making process needs to be extensive and includes a wide range of questions you should answer before choosing the best conveyor system for fragile materials.
Aside from being fragile, what other properties does your material have?
Define the following characteristics:
- Moisture content
- Bulk density
- Drop testing data
- Angle of slide
- Particle size and shape
- Material sensitivity
- Single material unit weight
All of these are important to consider when choosing the right conveyor type. For example, drop testing data will help you estimate the load capacity, and the angle of the slide is essential for preventing spills.
Ask yourself these questions: what are the places where your material is in free fall? Are there any sections of the conveyor where material can get stuck? What forces are acting on your material?
The goal here is to get your material from point A to point B in your facility without any problems.
Plenty of manufacturers offer materials tests to ensure that your specific material can travel through their systems while preserving its integrity. During a materials test, keep an eye on the parameters such as temperature, speed, and time spent in the conveying system. All of this will be crucial for your operations once the conveyor system is installed.
Facility Layout and Conveyor Modularity
How much space do you have? What does the layout of your facility look like? Will your conveyor require sharp turns, steep inclines, or other specific features?
Make sure that your conveyor can be configured to work with the layout of your facility. The last thing you want is for a machine or part of the system to get in the way and cause problems.
The most important consideration should always be safety. You want to make sure that no one gets hurt from damage or falls while handling fragile materials in food processing.
The best conveyor type would be a modular one that can be reconfigured depending on the layout of your facility.
The use of modular conveyors means that you can always configure the best set-up for your needs, even if there are changes in design or layout in the future. Modular conveyors (such as Cablevey tubular cable systems) are ideal for tight spaces that require unpredictable turns or angles because of their high flexibility and modularity.
Apart from safety, it is also vital to consider productivity and cost-effectiveness. Fragile materials handling requires accuracy and attention to detail. Fragile materials handling processes are not suitable for high production volumes, and therefore the use of modular conveyors is advised as this will reduce costs over time by increasing efficiency.
Protecting your products and materials from contamination is another important aspect. The production environment may not allow for contamination from airborne particles or from fingers touching the products during conveying.
Similarly, your facility environment should be protected from material particles, dust, or any other form of contaminants that may enter the system.
The use of a hood or other form of an enclosure will protect your process from contaminants and ensure a cleaner product at the end of conveyance.
Protected production environments are also required to maintain cleanliness during a breakdown, repair, cleaning, and storage processes as these steps can introduce new particles into otherwise pristine conditions.
One of the best choices you could make for your fragile materials is to transport them via enclosed conveyor systems.
Cleaning and Maintenance
Certain conveyor systems are well-suited for your material type but are not that easy to clean or repair. What does it take to clean your conveyor? Does it need to be disassembled entirely, or can your crew remove only the problematic parts without wasting time on taking apart the whole system?
It is essential to consider how much time your maintenance crew spends on maintaining the conveyor system. If they use up all of their time doing this, what happens when other equipment malfunctions need more immediate attention or repair?
Additionally, how easy is it to get a hold of replacement parts should something get damaged? Just like with vehicles, some conveyors have a higher replacement part cost than others.
With all of these points in mind, finding the conveyor that suits your needs and budget best is essential.
How big is your business? Do you need multiple conveyor systems, or just one? Are you planning on expanding in the future?
The hallmark of a successful business is that it does not stagnate. Companies evolve, grow, and expand. It is important to choose a conveyor that can keep up with the demands of your business so it doesn’t break down when you need it the most.
When thinking about the best system for your business, don’t just think about it as it is in the present moment. Envision your organization five or ten years from now. How many new facilities do you have? Has the space changed in any way? The conveyors that you invest in now will dictate the system you need in later years.
Never lose sight of the scalability of all of your systems. Easily scalable material handling equipment and processes lead to sustainable growth.
You want your conveyors to be reliable and built for the long haul, which is why you should invest in a heavy-duty system that can handle your current operations as well as those of tomorrow!
At last, the cost of your new material handling solution is vital in your decision-making process. The odds are that you don’t have unlimited resources to play with, which is why you need to figure out how much money your budget will allow.
The price tag of the new conveyor should not be a deciding factor; rather, it should be a guide that will help you make the right choice. Don’t settle for the cheapest system just because you wish to save some money – your conveyor will have a huge impact on your operation’s efficiency, and you’ll want to invest in the best possible option. The “pay now or pay later” rule definitely applies to conveyor systems – if you buy a cheap conveyor and it doesn’t work correctly, you’ll have to pay more in the long run.
Ensure to factor in the costs of installation, maintenance, and any other service contracts that go along with your purchase.
Fragile materials are common in all industries. In food processing, they are defined as materials that are brittle, delicate, sensitive to outside environments, or otherwise prone to damage.
They are best conveyed with a conveyor system that is specifically designed for these types of products. There are many factors to consider when you’re selecting the ideal conveyor, and it’s important to get professional advice before making your purchase so as not to regret it in the future. For example, you must consider the layout and floor space of your facility, the modularity and scalability of the conveyor, properties of the conveyed material, the budget at your disposal, and much more.
Choose between the following conveyor types: tubular cable conveyors, belt conveyors, vibratory conveyors, and wrap conveyors. All of these are suitable for transporting fragile products. Which one you will go for depends on your needs, as well as all the aspects mentioned above.
Remember that tubular drag conveyors are best suited for high-volume, low-speed applications, especially in spaces with high inclines or sharp corners.
If you’d like to know more about how cable drag conveyors can help your food processing business, please contact Cablevey Conveyors for more information.