Reducing Material Breakage With a Tube Conveyor System

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.

Tube conveyors

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 our sales team today. Our engineers will work with you to create a custom system that meets your specific needs.

Adapting and being resourceful seem to have been the key attributes of many businesses during the Covid-19 pandemic, particularly where operations changed quickly and maintenance routines were thrown off course.

As a global leader, we pride ourselves on being used to providing our customers with high levels of service and support, so not being able to visit many sites during the pandemic has been far from ideal, as we never want to see Spiroflow equipment neglected. Nonetheless, for those technical staff and in-house engineers who took on the challenge of maintaining our equipment over the period while we were unable to do so, we applaud you!

Having now returned to a state of near normality, we are eager to resume the maintenance of customers’ equipment by providing an initial examination and health check to ensure that everything is running as it should. Clearly, it’s in everyone’s best interest to ensure that machinery doesn’t breakdown, as the negative impact of skipping routine maintenance can be detrimental to production efficiencies and could result in:

  • Resources and productions losses
  • Unexpected downtime resulting in overtime labour
  • Having to subcontract
  • Material wastage from untouched resources


So, the sooner we can get to see customers the better. Plus, it will also help improve the lifetime of Spiroflow equipment and ensure that it operates to its maximum potential.

This ‘Spiroflow MOT’ can be done ideally during a time to suit, such as a shutdown period to avoid production interruption – whenever is convenient.

To book an appointment with our team of expert service engineers, please contact Amanda Blewitt, Spiroflow’s Service Coordinator (UK) on 01200 400624, or email

The food industry is one of the most important and highly regulated industries worldwide. The safety and quality of products that we consume depend on a variety of factors, including the cleaning and sanitation processes used to prepare them. The importance of cleanliness and sanitation cannot be overstated – from raw ingredients being stored under sanitary conditions to final packaging for consumers.

In this article, we will discuss how conveyor systems can help maintain sanitary conditions in the food industry, as well as some common cleaning and sanitizing options available for these systems.

Why is sanitation important in food processing?

According to the CDC, food-related illnesses and outbreaks caused by contaminated food cost the US economy $15.5 billion each year. The CDC estimates that there are 48 million cases of foodborne disease annually, leading to 128,000 hospitalizations and 3000 deaths per year on average in America alone.

Food contamination is a major public health concern not only for developed countries but also developing regions, where it is often difficult to maintain proper sanitation standards. The World Health Organization (WHO) states that foodborne diseases result in an estimated 600 million illnesses and 420,000 deaths annually worldwide.

The Food Safety and Modernization Act (FSMA) by the FDA is a major step forward in improving food safety requirements and preventing contamination of the US food supply. The FSMA establishes new controls for human and animal food to prevent intentional adulteration while also focusing on strengthening import/export inspection programs, among other initiatives.

The food processing industry is a place where cleanliness and sanitary conditions are absolutely critical, as the potential impact of contamination can be significant.

Sanitation efforts must focus on ensuring that food processing equipment and facilities do not come into contact with contaminated products or other materials that could potentially transmit harmful bacteria or viruses from one location to another.

Cleaning vs Sanitation

Even though they are often used interchangeably, it is important to understand that there are differences between cleaning (washing) and sanitation. The word “sanitary” implies that an object or process has the potential to reduce microbial levels on a surface, which can help protect people from food borne illness.

The key difference comes down to whether cleaning products kill microbes (sanitation) or simply remove them (washing). The proper level of sanitary protection will vary depending on the type of food materials being transported, but it is important to understand that even a cleaned conveyor can still contain microorganisms.

A well-designed sanitary conveyor system should be gentle enough not to damage fragile foods during transport, and it should also ensure safety for workers and consumers by removing and killing any pathogens that may be present.

Sanitary Standards

So, what are the sanitary standards for conveying in food production?

The USDA and FDA have strict guidelines for sanitary frame designs and maintenance of conveyors in food processing facilities. The FDA has a set of Recommended Good Manufacturing Practices that outline specific components required to maintain product safety, including:

  • The design must not allow any contaminants into the product stream during operation.
  • Hazardous materials cannot be used when constructing or assembling conveyor components. The FDA recommends stainless steel conveyors or those made from other corrosion-resistant materials.
  • The conveyor must be easy to clean and sanitize at all times, ensuring that there is no chance of product contamination or adulteration during transport.
  • The structural design should allow for the cleaning and disinfecting of any crevices between moving parts such as chains and sprockets without requiring disassembly by hand (which could lead to product contamination).
  • The conveyor belt and any rollers should not have areas where product residue can collect, as this may result in cross-contamination of incoming goods while being processed.

These are just a few of the important considerations that companies must take into account when designing their conveyors systems. The FDA recommends consulting with a food safety expert to ensure compliance and best practices are met at all times, as product contamination can easily happen if these guidelines aren’t followed properly.

3-A Sanitary Standards

A useful set of standards to consult with when designing a sanitary conveyor system are the 3-A Sanitary Standards. They are voluntary guidelines for construction and design of processing facilities in the food industry. The standards are extremely thorough in their description of sanitation requirements with many illustrations included to better understand a wide variety of components involved in sanitary conditions within these different sectors.

Even though 3-A Standards are not regulatory, some state regulations may reference them. The standards were first introduced in the 1920s and have changed over time to reflect new technologies, best practices, and lessons learned from field experience.

The four associations in charge of the standards are the American Dairy Products Institute, International Dairy Foods Association, Food Processing Suppliers Association and the International Association for Food Protection, with support from both trade associations, government agencies like USDA and FDA, as well as various equipment manufacturers.

Some examples of 3-A Standards include specifications for materials that conveyor systems can be constructed with, proper installation and maintenance of equipment that comes into contact with food products, and procedures for receiving new conveyor systems to ensure they are sanitary. The standards also include specifications for design elements like the slope of a floor (to avoid water accumulation), types of doors on an enclosure (for ease in cleaning), light levels inside processing areas or storage rooms (for safety and to more easily see and inspect the processing environment), and more. The list goes on!

Features of a Sanitary Conveyor

Keeping the above-outlined guidelines and conveyor knowledge in mind, there are several features that sanitary conveyor systems should have in food processing facilities. The following should all be included:

  • Enclosed system – The entire system should be enclosed, ensuring that no contaminants can enter the production line. Enclosing all areas where product is handled or transferred (i.e., ingredient feeders and discharge points), as well as any open spaces along the length of the conveyors will help to keep the system sanitary.
  • Few moving parts and cracks, holes, or crevices – The fewer moving parts there are in the conveyor system, the easier it will be to clean and sanitize. There should be as few nuts, bolts, screws, and joints as possible to reduce the risk of product accumulation. The conveyors should also be smooth and seamless to prevent any hiding places where food residue can settle.
  • Stainless steel connectors – As mentioned above, stainless steel connectors are best to use when constructing the conveyors, because these materials do not corrode or rust.
  • Clean-in-place technology – CIP technology is the automated cleaning of machinery with chemical solutions. The conveyors should be equipped for CIP technology, which allows food processors to implement a thorough sanitization program based around pre-set cycles and schedules. The application of chemicals during this process will remove any residual product particles or residues that may have built up over time on the system. Another great feature of CIP is that the conveyor system doesn’t have to be disassembled to clean, allowing for less downtime and a more efficient cleaning process.

Best Sanitary Conveyor Options

Which conveyors are the most sanitary for food processing?

To sum up our features from above, the best option would be a stainless steel conveyor system (or one made from other corrosion-resistant materials) that is enclosed, has few moving parts and crevices, and is equipped for CIP technology.

The following conveyor systems would meet some or all of these requirements:

  • Belt conveyors – These are one of the most common types of conveyors used in industries today. Food grade conveyor belts should be made of non-porous material, and they could also be enclosed if need be. However, they do require quite a bit of floor space, because they can only operate on the horizontal or near-horizontal plane.
  • Tubular drag cable – Depending on what type of food material you are transporting, tubular drag cable and disc conveyors can be the best option. The cable is often made of stainless steel coated in smooth nylon where food products are in contact with it. Nylon is resistant to acids and other chemicals, so it is a good choice for food processing. The cables are enclosed in tubes to further protect the product from contaminants. Material is moved with the help of solid discs that have no crevices, nuts or bolts. The system can be designed with many options to accommodate different types of food products, making it versatile.
  • Chain drag conveyors – The chain drag conveyor is similar to the tubular cable drag conveyor, in that there is a stainless steel chain and the system itself can be enclosed. The main difference between this conveyor type and tubular drag cable, however, is that the chain is not the best option for transporting food material. The chain can accumulate product residue, which can cause contamination issues down the line if not cleaned properly.
  • Pneumatic conveyors – A pneumatic tube is usually made of stainless steel, and it can be either horizontal or slightly inclined (for gravity flow). The top-end should have a filter to eliminate any particles that might make their way in during operation. Pneumatic tubes could also be equipped with CIP technology which makes them sanitary conveyor options. However, without the CIP technology, the pneumatic tube is largely inaccessible and could make cleaning difficult.

Cleaning Processes

Regardless of which conveyor system you decide on, a thorough cleaning process should be a part of your cleaning and sanitation program.

The most important aspect to focus on when it comes to cleaning conveyors is that all remnants from the product are removed completely, no matter how small they may be. The benefits of establishing a regular cleaning schedule are many, including protecting the product from contamination, extending conveyor life, and ensuring safety for workers.

What cleaning options exist for conveyor systems?

The two primary choices could be divided into hand cleaning and automated cleaning.

Manual cleaning

Unfortunately, plenty of facilities still use cleaning by hand. The people who do the cleaning can wear gloves and use brushes or scrapers to remove any visible residues. The process varies depending on the type of food product being transported (snack foods, frozen foods, specialty grains, etc.), and it can be done more or less frequently based on the amount of residue left from previous runs.

This type of cleaning is less than ideal. The process is not effective for removing all contaminants, and it can take up a lot of time. The employees themselves are also at risk if they do not wear the proper safety equipment or follow sanitary guidelines when cleaning with brushes and scrapers.

CIP and COP cleaning

Automated, easy cleaning comes in the form of CIP, or Clean-In-Place, systems. Compared to manual washing, CIP doesn’t require too much time and effort, and it can be done without the risk of contamination. The food product does not come into direct contact with any tool or machine outside of its normal conveyance process.

Another significant benefit to CIP technology is the fact that conveyor systems don’t have to be dismantled to be cleaned (no tools required). The system is hooked up to a CIP unit and the product runs through it, which means that there’s no downtime during cleaning.

Cleaning out of Place (COP) systems are also an automated option for conveyor clean-up. The difference between this technology and CIP is that COP has smaller pieces that are removed from the conveyor and taken to a separate area for washing. The time required is greater when using COP instead of CIP, but it’s still more efficient than manual cleaning techniques.

Cleaning Protocols

Every conveyor manufacturer has its own set of cleaning protocols that must be followed when it comes to sanitizing their conveyors.

The manufacturer should also provide thorough instructions on how to install and operate the system, as well as perform regular cleaning procedures.

For example, Cablevey offers two types of cleaning for their systems: wet and dry cleaning.

Dry cleaning may include one or several of these items:

  • Air knife – Using compressed air to blow off the conveyor line.
  • Brush box – A line insert with brushes used for cleaning.
  • Sanitizing cleaner and sponge box – A combination of sponges and sanitizing chemicals.
  • Urethane wiper disc – The wiper disc is used to wipe off any remaining residue from the inside of the conveyor.

In contrast, wet cleaning consists of the following steps:

  • Water rinse – A high-pressured water spray rinses the conveyor, getting it ready for the next wash step.
  • Foaming agent – The purpose of the foaming agent is to clean the inside of the conveyor, removing any remaining residue.
  • Sanitizing agent – The sanitizing agent is used to kill any microorganisms that may still be present on the conveyor.
  • Second water rinse – The last step in the cleaning process is a water rinse, which makes sure all residues and chemicals are removed from the system before it can start operating again.

Before you settle on a new conveyor system, make sure to do some research first on the cleaning protocol capabilities of each manufacturer.

Validation, Monitoring, Verification

A cleaning and sanitizing protocol cannot be effective without proper validation, monitoring, and verification methods. The purpose of validation is to make sure that the protocol will actually yield the desired results. The monitoring step consists of checking if all protocol steps are being completed successfully, while verification is used to determine if there are any remaining residues left on the surface that should have been removed by the cleaning and sanitizing process.

Validation consists of microbiological and non-microbiological tests for assessing the cleanliness or contamination of a conveyor surface.

Microbiological tests include culture cultivation and molecular methods. The purpose of these tests is to determine if any microorganisms are left on the surface after cleaning. The most important aspect in this process is minimizing test variables, which means ensuring that there isn’t any other source of contamination around when testing takes place.

Non-microbiological tests include visual assessment, ATP tests, protein tests, and other assessments. The purpose of these is to determine if the surface has been properly cleaned and rinsed, which results in a system free of residual soil.

Without proper validation and verification, you cannot be sure that your conveyor system is hygienic. The consequences of not properly validating and verifying can be extremely dangerous to the end user, as there may still be some types of bacteria and residual soil present on the surface even after cleaning and sanitizing.

ATP Tests

One of the best ways to test whether or not your cleaning protocol is effective is by testing conveyor surfaces for molecules of ATP (adenosine triphosphate). ATP represents a source of energy in a living organism – it can be found in food residue, bacteria or mold, and even human skin.

ATP surface tests are highly efficient and sensitive. A simple swab of (vertical or horizontal) surfaces after the cleaning process (but before sanitization) is enough to verify whether the cleaning process is working. If there is a high amount of ATP, then the cleaning protocol needs more tweaking.

A unique feature of this testing process is that there is not one acceptable range for ATP that can be applied to every single surface or conveyor. The pass and fail numbers depend on the age of the surface, material of the surface, what type of product came into contact with the surface, how it was cleaned, etc.

To set a reasonable ATP limit for your specific surfaces, you will need to perform intensive ATP swabbing and testing for a period of time (two or three weeks) to establish baselines for your use case.


In the food processing industry, sanitary conveyor systems are paramount for the safety of consumers. The best way to ensure that your system is fit for purpose, and can be cleaned thoroughly without having too much of an impact on productivity, is by doing research beforehand.

The manufacturer should also provide detailed instructions regarding all aspects surrounding installation and regular cleaning procedures of each particular material handling system.

The ideal sanitary conveyor for food processing should have an enclosed system, and no holes, crevices, nuts, or bolts for residue and bacteria to hide in. The conveyor should also be easily accessible for cleaning purposes, ideally without needing to be disassembled completely.

If you are interested in conveyors that are enclosed, with proper cleaning mechanisms, which are gentle on the materials, and energy-efficient, please contact us. We will be happy to help you find the best solution for your company.

Spiroflow Joins May River Capital Material Handling Equipment and Industrial Automation Platform, Automated Handling Solutions

May River Capital, a Chicago-based private equity firm focused on lower middle market industrial growth companies, announced today the creation of Automated Handling Solutions (, a newly established platform offering highly engineered material handling equipment and automation solutions. The platform was formed through the combination of two specialty conveying and material handling businesses: Spiroflow, a global manufacturer of material handling equipment and provider of control systems integration, and Cablevey Conveyors, a market leading manufacturer of patented tubular drag conveying systems for food and beverage and high value industrial applications. Together, the combined companies will offer a differentiated and comprehensive suite of material handling equipment and industrial automation solutions to marquee customers globally.

“We are thrilled to welcome Spiroflow and Cablevey to the May River portfolio. We see an extraordinary opportunity to invest and grow these market-leading brands under one platform. With these foundational assets, we expect to further accelerate the profitable growth both Spiroflow and Cablevey have seen during the past several years,” said May River Partner, Steve Griesemer. “The specialty conveying sector is a high growth segment serving attractive end markets. Under the new platform, Cablevey and Spiroflow are uniquely positioned to serve this growing demand and build upon their track records of delivering innovative solutions to global customers.”

Founded in 1971 by Michel Podevyn and based in Monroe, North Carolina, Spiroflow offers one of the most comprehensive lines of handling equipment and complementary automation solutions in the industry, including flexible screw conveyers, bulk material filling and discharging equipment and integrated control solutions. Spiroflow was a pioneer and early innovator in flexible screw conveying. During its history, the company has built a strong reputation as a provider of precision material handling equipment used in high value applications in markets such as food and beverage, pharmaceutical, nutraceutical and specialty chemical end markets.

Through the leadership of Podevyn and CEO and Co-Chairman Jeff Dudas, Spiroflow has achieved significant recent growth in both the US as well as the UK, where the business was founded and still has a key facility. With installations in more than 50 countries, the company’s technology is known for its safety, efficiency and reliability, serving some of the most demanding material handling applications.

“We’ve come a long way during the past 50 plus years, as we’ve built a company that has become an important and reliable partner to our customers,” said Podevyn. “We could not be more excited for the Spiroflow team to take the company to the next level through its new partnership with May River Capital.”

“With the additional financial and operational resources May River brings, we are excited to continue to invest in the business and drive growth. We believe this new partnership will further our track record of innovation and expansion that has served our customers, employees and the entire Monroe, North Carolina, and Clitheroe, UK communities well during the past several decades,” said Spiroflow CEO and Co-Chairman Jeff DudasDudas will continue with Spiroflow as interim CEO, focusing on advancing growth-oriented initiatives through his deep network of customer and industry relationships.

“Spiroflow’s portfolio of conveying, storage, automation integration and system designs, combined with a North American and European presence, have positioned the company perfectly to catalyze this new platform’s growth,” said May River Executive Resource Group member Brad Sterner, who is acting CEO of Cablevey and will become Executive Chairman of AHS. “We will leverage May River’s ownership of both the Advanced Material Processing (AMP) process equipment platform and AHS to drive continued market share gains in our served global, high growth end markets of food, pharmaceutical, nutraceutical, chemical and general industrial sectors.”

Winston & Strawn served as legal counsel to May River. BDO, Capital Advisors, LLC served as financial advisor, while Shumaker, Loop & Kendrick, LLP served as legal counsel to Spiroflow and its shareholders.

About May River Capital

May River Capital is a Chicago-based private equity firm focused on investing in lower middle-market, industrial growth companies. May River Capital invests in high-quality industrial growth businesses, including precision manufacturing, engineered products and instrumentation, specialized industrial services, and value-added industrial distribution services. For more information, please visit

About Spiroflow

Spiroflow is a global leader in the field of powder handling and dry solids processing and an emerging leader in control systems integration. Throughout the company’s 50-plus-year history, its design engineers and process automation teams have provided customers with the safest, most efficient, and most reliable conveying and handling solutions available. Learn more at

About Cablevey Conveyors

Cablevey Conveyors is a global specialty conveyor manufacturer that designs, engineers, assembles and services tubular drag cable and disc conveyor systems. With customers in more than 65 countries, the company specializes in moving materials for food/beverage and industrial powder processors that seek food-grade conveying performance with systems that are clean, fast, energy-efficient and cost-effective. Learn more at

Before it is packaged, tea is handled in loose leaf or instant powdered form. Both forms come with challenges that must be overcome via conveyor system design to ensure a final product that is consistent in both flavor and quality. In this article, Spiroflow experts will discuss tea conveying challenges and review considerations for the mechanical conveyors most suitable for conveying tea.

Tea Conveying Challenges

Degradation – Friable tea products are prone to degradation, which can cause undesired flavor variations. A conveyor featuring gentle handling will prevent and protect the product from bruising and breaking tea leaves. In addition to impacting flavor, excessive degradation resulting in too fine of a product can cause challenges with separation and blending.

Dusting & Safety – Additionally, conveying tea can result in considerable amounts of fine combustible dust which, if not contained, is extremely dangerous – as static buildup from conveying tea leaves increases the risk of explosion. To minimize this risk, select an enclosed conveying system with dust containment features.

Abrasion – Tea in leaf form is somewhat abrasive and can lead to higher rates of wear and tear, so selecting a conveyor that will stand up to the job and from a manufacturer that can quickly deliver spare parts will be important.

Fast Turnaround During Flavor Changes – Lastly, manufacturers producing flavored teas, both in instant and leaves, may run multiple blends in a single day on the same equipment. Quick clean features of the conveyor to prevent residual flavor transfer between batches – while minimizing downtime – is key.


Flexible Screw Conveyors

Ideal for: Tea blends & flavored teas
A flexible screw conveyor is made up of one moving part – the spiral inside a tube. Because of this, the flexible screw conveyor is a very versatile and low cost conveyor. These conveyors are idea for conveying blends of tea or flavored teas.

Key Benefits

  • Fast cleaning and turnaround between flavored tea batches to prevent residual flavor transfer when running multiple blends in a day (via easy clean quick release flanges)
  • Maintained batch integrity (via constant remixing of the blend via the screw conveyor’s helical motion)

Aero mechanical Conveyors

Ideal for: Loose Leaf & instant 
The aero mechanical conveyor creates an airstream which moves the product up the tubes along with high-speed discs and a rope. This conveyor is a great choice for conveying both instant tea and loose leaf tea. Adding to its benefits, the aero mechanical conveyor runs quietly and with minimal energy requirements.

Key Benefits

  • Total tea dust containment (via airtight operation)
  • Reduced risk of explosion (caused by static build up of combustible tea dust)
  • Gentle handling of friable tea leaves (air pockets in airstream support with gentle conveying)


Cable Drag Conveyors

Ideal for: Loose Leaf & instant, where layout versatility is a requirement
Similar to the aero mechanical conveyor, a cable drag conveyor operates using evenly spaced discs connected by a rope. However, it drags the products along the cable and disc assembly gently at reduced speeds rather than moving it quickly via very fast moving airstream, vacuum or air blasts. Additionally, cable drag conveyors offer conveying in multiple planes and with multiple inlets and outlets while also operating at reduced clearances – for maximum layout versatility.

Key Benefits

  • Best choice for minimal product degradation of tea leaves due to extremely gentle handling (no vacuums, fast moving air blasts, belts or buckets that can potentially cause damage)
  • Total tea dust containment (via contamination free totally-enclosed system)


Need help evaluating the best conveyor and bulk material handling system solution for your tea application?

We can replicate your on site conditions in our professional test lab and, with our broad range of conveying equipment, help you determine the best conveyor for your tea product. Contact us today for a consultation with one of our engineers.





Low-bulk-density powders with small particle size, low to zero moisture content and low to no cohesiveness can become easily aerated during bulk bag filling leading to poor bulk bag densification. In addition to especially challenging lightweight powders, many other powders, pellets and granules’ material properties make them prone to aeration during filling and difficult to compact. In fact, reducing the amount of air that enters into the material during the filling process is one of the greatest technical challenges in bulk bag filling.

This article will:

  • define and discuss the relationship between aeration and densification
  • outline the challenges and risks that arise from aeration during the filling process
  • discuss bulk bag filling system solutions to increase bagged material density

What is aeration with respect to bulk bag filling and when is bulk bag densification critical?
Due to certain material characteristics such as particle size and shape, some products tend to trap air between particles resulting in reduced bulk density and stability of the material. This can be compounded by aeration during the bulk bag filling process which is the introduction of more air into a dry bulk material being filled in a bulk bag. A good indication of whether a material will benefit from densification during the bulk bag filling process is the difference between its tamped (density of the material once it has been compacted via vibration), and un-tamped bulk density. The use of a sophisticated densification system such as Spiroflow’s CTE Cone Table can result in significant deaeration of the filled bulk bags which has several benefits discussed below.

What happens to filled FIBC bulk bags that have not been deaerated / have poor densification?
When air is trapped or introduced in between powders and other solid particles during the bag filling process, the material can behave more like a liquid than a solid and be extremely unstable during transportation and storage. These bags will be unsafe to stack in storage and shipping, increasing shipping and storage costs, and can be prone to tip over onto an operator, creating a safety risk. Highly-densified, compact bags with flat tops, on the other hand, are safer and easier to handle, stack and store.

A bag filling process that results in aerated, poorly densified bags can result in trailers being shipped under max weight, significantly increasing transportation costs. In addition, if the same weight of material can be achieved in fewer or smaller bags there can be a significant saving in bag costs.

Air (oxygen) in the bag can also pose a health risk for the food and beverage industry – bacteria feeds on oxygen. More oxygen in a bulk bag means that the food product or ingredient will not last as long in storage. While densification can help reduce the amount of air (oxygen) in bulk bags, if this is also a critical factor you could also consider a nitrogen purging fillsystem, which fills the bag with nitrogen prior to and during filling and then seals the bags to minimize product exposure to oxygen.

Bulk Bag Densification Filling System Options

A safe and effective bulk bag filling process aims to deaerate material as close as possible to its tamped bulk density and remove the angle of repose formed by the peak of material when pouring a dry bulk solid for a safer, more stable, flat-top bag.

Vibratory Deaeration Deck / Platform / Table
Most bulk bag filling densification systems use some type of vibration technology on the bulk bag filling platform / table (on which the bag sits while it is is filled) in order to better compact and densify the product in the bag. A programmable vibratory deaeration deck can help to densify the material at timed intervals during the bulk bag filling process and minimizes filling cycle times while improving bag stability.

However, it is important to compare vibratory decks as they are not all designed the same and thus, do not deliver the same vibratory force or rate of densification.
The Spiroflow Cone Table Elite (CTE) High-Density Bulk Bag Filler’s patented cone table densification is ideal for powders, granules or pellets that have a significant difference between their tamped and untamped bulk density or are easily aerated during bag filling. The CTE filler’s unique coned densification table makes direct contact with the bag resulting in maximum vibration energy transfer. The cone shape directs product to the bottom corners of the bag to create a stable foundation and pushes up a column of product every time it comes into contact with the bag, removing the angle of repose. Its assembly consists of a truncated pyramid welded on a frame with two integral electro-mechanical vibrators.

The Spiroflow Cone Table Elite Process

  1. Build a stable base 

2. Transfer maximum energy 

3. Stretch the bulk bag

4. Removes the angles of repose 

Bag Stretch for Improved Bulk Bag Densification
When using the Spiroflow Cone Table Elite Bulk Bag Filler, a bulk bag still typically spends 50% of the filling cycle hanging from its loops which promotes stretching of the bag. As a bag stretches during filling, volumetric efficiency increases. A stretched and densified bulk bag will not slump and will hold more product. Additionally, due to the unique design of the Cone Table, bag stretching is also improved during the periods of densification.

In other densification methods, bulk bags are not hung by their loops during filling; the introduction of a vibratory filling deck or table means that the bag maintains contact / is sitting on the table through the cycle, preventing the bag from stretching.

Don’t Sacrifice Speed for Best-in-Class Bulk Bag Densification
When it comes to bulk bag densification, many traditional systems will result in a significantly slower fill cycle due to the time it takes the machine to allow material to settle and stabilize. Because of the unique design of the CTE filler, fill rates of more than 40 bags per hour can still be achieved on a semi-automated bag filling line.

No More Unsafe, Unstable Bags
When a bulk bag is properly stretched during filling and the material is deaerated with a flattened angle of repose for a flat bag top, the result is a very safe and stable bag. Learn more about how the cone table on our CTE Bulk Bag Filler can deaerate your material or fill out the contact form below with questions.