In many industries, the integrity of the materials or products being conveyed is of utmost importance. This is especially true in the food processing industry, where materials are particularly fragile, and breakage can lead to many negative consequences.
However, even though preserving material integrity is crucial during the conveying process, a whopping 29% of industrial facilities state that material breakage is one of the top three conveying challenges they face on a daily basis.
In this blog post, we’ll take a look at some of the most common causes of material breakage and explore how a tube conveyor system can help to reduce or even eliminate them.
Why is material integrity important?
Material breakage is defined as the separation of material particles into two or more pieces under the action of stress. Any place where the product or raw material is sliding against a conveyor surface (be it a tube, flat surface, or any other) can cause material abrasion and possibly material breakage.
Operations such as grinding or mixing intentionally break the material down into smaller pieces to make it easier to process. These are value-added processes that serve a particular purpose in production.
However, outside of operations such as these, breakage generally leads to a decrease in product value. In the food industry, even the smallest amount of breakage can lead to lost product, sanitation issues, and decreased efficiency.
Preserving material integrity is particularly important in the following cases:
- When the material is easily degraded, such as in the case of friable materials, fragile materials, or materials otherwise prone to damage.
- When the consistency of blends or mixes must be preserved. This is vital for snack foods, breakfast cereals, tea blends, and other products that require an even combination of ingredients.
- When product dusting is a concern, some materials create more dust than others when they are broken. It can lead to respiratory issues for workers, equipment malfunctions, and other dust hazards, including dust explosions.
In short, breakage costs money – whether it’s wasted product, downtime for repairs, or poor quality products that need to be reworked or scrapped.
The ultimate goal of every production facility, especially if they’re dealing with specialty materials or blends/mixes, should be to find ways to reduce or eliminate material breakage altogether.
But to do that, we need to first understand what causes it.
Why does material break?
The main reason why material breaks during conveying is due to impact. The two most common types of impact are:
- Free-fall impact
When fragile material is dropped, thrown, or otherwise falls from a high point, it’s likely to break.
Free-fall impact commonly occurs when a material is transferred between different conveyors when fed into the conveyor or discharged from it.
This type of breakage is commonly seen in bucket elevator systems and other gravity-based conveyance systems. As the material is lifted and then released into the chute or trough, it drops and collides with the surface below, which can cause it to break.
- Collision impact
Collision impact happens when two pieces of conveyed material collide – for example, two particles hit each other in mid-flight. It also occurs when a particle collides with a stationary element, such as a conveyor wall, a belt, a pipe, or other conveyor components.
This type of breakage is commonly seen in screw conveyors and pneumatic conveying systems. The particles travel at high speeds as they move through the system (especially in pneumatic conveyors), and when they collide with an object, it can cause them to break.
Other potential causes of breakage include:
- Excessive vibration
- High temperatures
- Chemical erosion
- Electrostatic discharge
- Moisture damage and more
While all of these factors can contribute to material breakage, collision impact is the most common cause. In the next section, we’ll take a look at how tube conveyors can help reduce or eliminate it and some other factors that cause the material to degrade.
How to prevent material breakage
Some general advice for preventing material breakage includes:
- Using vibratory feeders instead of rotary airlocks or a screw feeder – Vibratory feeders help minimize the amount of breakage at the inlet without using the rotary shaft of a screw feeder or blades from a rotary airlock.
- Smooth speed change – When the speed of the conveyor changes, it can cause a sudden impact that can break the material. Try to gradually make any speed changes (accelerations or decelerations) to avoid this.
- Using gentle curves – Curved sections in your conveyor can cause the material to slow down and make more contact with the surface below, which increases the chances of it breaking. Avoid using sharp curves, or use a low-friction material for the surface to help reduce the amount of contact.
- Monitoring temperature and humidity – Make sure that the environmental conditions in your facility are within the recommended ranges to help minimize material degradation.
Now let’s take a more specific look at how tube conveyors can help to reduce or eliminate material breakage.
A perhaps obvious but often overlooked solution to reducing or eliminating material breakage is a gentle conveying system. It will use low-speed, high-volume movement to slowly push the material along the conveying line without too many contact points – meaning no impact and no breakage.
This is where tubular conveyors come in. A tube conveyor is an enclosed system with a tubular loop to move material through a facility. The material is fed into the first tube, and as it moves through the tube, it is gradually and seamlessly transferred to the next one. This process continues until the material reaches the end of the conveyor.
The material is moved thanks to circular solid discs evenly spaced along a cable that runs the length of the tube. These enclosed discs gently push the material along. The discs are connected to a gearbox, which is connected to a motor. The speed of the motor determines the speed of the discs and, therefore, the speed of the material.
Because there are no abrupt changes in direction or speed, and because the discs are constantly moving the material along, there is virtually no chance for it to break.
Tube conveyors are also ideal for preventing material degradation. They can be designed to operate at low speeds, which means that the material has less chance of being exposed to excessive vibration or high temperatures. And because of the material the conveyor is constructed from (stainless steel), there is also no risk of chemical erosion or electrostatic discharge.
Due to the enclosed nature of the tubular conveyor, environmental conditions (temperature and humidity) can be more easily controlled, which is another way of minimizing material degradation.
In addition, tube conveyors can be customized to your specific needs (especially Cablevey tubular drag cable and disc conveyors). This means that you can configure them to move the material along a path that minimizes contact points and reduces the chances of collision impact.
Tubular cable vs. chain disc systems
If you are looking at tubular drag conveyors to help reduce material breakage, you may be wondering whether a tubular cable or chain disc system is best for your needs.
In terms of preserving material integrity, cable disc systems have the edge over tubular chain systems. This is because the material is less likely to snag on the nylon-sealed cable and discs, leading to less breakage. The exposed chain links of a chain conveyor can catch on the material, which can cause it to tear, break and accumulate.
Also, cable and disc conveyors are infinitely more sanitary and easier to clean than chain and disc conveyors. This is because there are no nooks and crannies for bacteria or other contaminants to adhere to in cable and disc systems instead of chain and disc systems. In terms of maintenance, cable and disc tube conveyors are also a better option.
Protecting the integrity of your material is important to the quality of your product. In the food processing industry, this means preventing material breakage, which can be done in a number of ways, but a tubular material handling system is one of the most effective.
By using gentle conveying methods and low-speed, high-volume movement, you can move your material along without too many contact points, minimizing the chances of breakage. And because of the construction of a tube conveyor – from the materials used to the way it’s designed – you can also minimize material degradation, ensuring that your product is of the highest quality.
If you’re looking for a conveyor system to help keep your material intact, don’t hesitate to contact Cablevey conveyors today. Our engineers will work with you to create a custom system that meets your specific needs.