In this study, I am going to share with you the key aspects I learned from 9 different roll compactors. During my study, the main focus was on reputable manufacturers of roll compactor machines such as: SaintyCo, Bepex, Gerteis, Alexanderwerk AG, The Fitzpatrick Company, Freund-Vector Corporation, etc.
My key areas of focus were:
- Parts of pharmaceutical roll compactor machines
- Overview of the working principle of roll compactor
- Roller compactor technology
- Technical specification of roll compactor machines
- Features of roll compactor machines
- Advantages and disadvantages of roll compactors
- Factors that determine the efficiency of roll compactor
Whether you’re new or a professional to pharmaceutical roll compactors, I’ll make this analysis simple and easy to understand.
Let’s start by defining what this machine is all about:
1. Parts of Pharmaceutical Roll Compactor Machines
A roll compactor machine is made of many parts that may vary depending on the complexity of the specific equipment. Take for instance, this video:
Clearly, you can see that a roll compactor has many parts. This is quite vivid from the installation process.
The complexity of the design is mainly due to the advancement in the roller compaction technology.
Still, a roller compactor is made of three main distinct sections:
· Roller Compaction Feeding System
It is the main section that conveys material or powder to the compaction area. Quite a number of machines use a screw mechanism.
· Powder Compaction Unit
This section is made of two rollers that rotate at a predetermined speed. Depending on the design, they may be knurled or soft.
In most cases, they are counter rotating rollers that apply a given amount of force to the material. As a result, it produces the required material density.
· Reducing Size of the Final Product
Depending on the specific requirements of material processing in the pharmaceutical industry, you will wish to reduce material to the required size.
In this section, you will reduce the ribbon to the required size.
Below is an image showing a summary of all the essential components of roll compactor machines.
These are critical sections of dry granulation machine
Apart from these vital sections of pharmaceutical roll compactor machines, another important aspect that we analyzed during the study was:
2. The Working Principle of Roll Compactor Machine
I think much of this aspect has already been illustrated in the video above, alongside an article I wrote on “The Working Principle of Pharmaceutical Roll Compactor Machine”.
In all the 9 different models of roll compactor machines, the working principle is the same. This is irrespective of the design and structure of the machine.
But still, let me do a summary of how a roll compactor works. I think this will help you have a quick summary of what you have learnt.
This is what you need to know:
First, the powder is fed into the compaction chamber from the material feeding hopper. This takes place accurately and precisely with the help of a screw feeding system.
You can see this from the video above.
Second, as the powder enters the compact zone, the two counter rotating rollers press, the fine powders to produce solid compact sheets.
At times, these solid compact sheets are referred to as flakes or chips.
To ensure the powder from the hoppers is fed directly on the two rollers, you can control the movement of feed screw with the help of an AC variable frequency drive (AC VFD). This ensures all powders pass strictly between the rollers.
To achieve this, you need to synchronize feed screws and roller speed. It is the only way of producing quality and consistent flakes or chips.
Again, you need to select the right size and type of rollers for dry granulation. That is, you may choose smooth surface or knurled roller.
This way, you not only ensure accurate material processing, but also reduce cross-contamination and dust.
Don’t worry, in case you’re new to pharmaceutical roll compactor machines. We’ll help you choose a machine with the right parameter.
You’ll also learn more about roll compactor specifications shortly.
Third, with the help of a multi-mill machine or oscillating granulator machine; the flakes or chips from the compacting zone are reduced to the desired size of grain or granules. The roll compactor is equipped with sieves that help to grade the final product.
By the end of this process, you should have this:
A fully processed powder from roll compactor
As you can see, this is a straightforward process.
NOTE: Even though the design or structure of the roll compactor may vary, the working principle is still the same.
As roll compactor manufacturers, we are constantly improving the working and functionality of our machines.
To know the development in the industry, we decided to analyze how technology has evolved in the roll compactor machines.
Here is what we realized:
3. Technological Advancement in Roll Compactor Manufacturing Process
In this section, I will take you through all the roll compactor machines technological advancements. I believe this will help you make a noble decision when choosing an appropriate machine for pharmaceutical or food processing industry.
Below are some of the most common technological advancements:
· Negative Pressure Air Pump
In pharmaceutical roll compactors, these pumps are configured such that they pre-clean the working chamber of the machine. That is, it will help clean the entire system such as keeping it free from residual powders.
This ensures the material bucker; sieves, pressing wheel and charging barrel are hygienic.
· Fully Automated System
Automation is an essential aspect that ensures efficiency and consistency during the entire manufacturing process.
Control system of an roll compactor machine
Some of the key components of automation include: PLC software, automated feeding control system and touch screen HMI.
Ideally, you can control every aspect of the machine such as the compression force of the rollers, speed and mount of power; among other aspects.
Other roll compactor manufacturers have machines with printers to print batch data while others can upload the process to the cloud system.
Our automated system can fully coordinate all operations of the roll compactor such as: Radial up and down movements of the systems. Besides, it automatically lifts the feeder thereby coordinating both screw rods and star types.
A good example of a roll compactor machine that features such a sophisticated technology is our RC-series of Roll Compactor machines.
· Precise and Accurate Driving Mechanism
As a leading roll compactor manufacturer, we have adopted an AC variable frequency drive (VFD), which ensures accuracy and consistency of the entire process.
A variable frequency drive
This is for both the screws and rollers hence, the ability to control the entire process.
· Advanced Safety Measures
We equip our roll compactor machines with the necessary alarm systems. These include slipping clutch that we have installed between the feed screw and gearbox.
A section of roll compactor machine
Other measures include: covering all moving parts and interlocking electrical components. For example, the fixed screw drive and main roll drive are interlocked together.
· Hydraulic and Pneumatic Systems
Adopting either a hydraulic or pneumatic system in some sections of the roller compactor has improved performance and reliability of these machines.
For instance, we use hydraulic systems to control feeder and hopper assembly. This makes it easy to dismantle and clean.
A rotating component of a dry compactor
Furthermore, we use pneumatic vibration screening to control powder processing by adjusting the valve appropriately.
Clearly, you can see that we have adopted a technology that aims to improve performance and reliability of every machine.
Apart from these, another essential aspect of roll compactors for dry granulation that we analyzed is the technical specification of the compactor machine.
How do you specify these machines when placing an order? Well, here is all you need to know.
4. Technical Specification of Roll Compactors
Whether you’re looking for our standard or custom made pharmaceutical roll compactors, it is important to describe the machine in some technical terms. This will enable us to design a roller compactor that meets your specifications.
Take for instance these specifications:
Technical specification of a roll compactor machine
Basically, you need to specify the following technical specifications of roll compactor machines:
|Parameter||Units of measurement||Comments|
|Model||–||Type of machine based on manufacturer’s product line. For instance, at SaintyCo we have RC-150C and RC-5B series|
|Feed screw speed||RPM||Speed at which the feed screw rotates.|
|Roll speed||RPM||Speed of a step pulley drive|
|Roll drive motor||KW or HP||Power consumption|
|Feed screw drive motor||KW/HP||Motor power consumption|
|Type of roll||–||Describes the physical appearance of the roll, which may be smooth or knurled|
|Roll force||Kg or tons||Maximum amount of force a roll exerts on powder|
|Roll diameter||mm or cm||Size of the roll|
|Output||Kg/hour||Amount of processed product the machines produces|
Apart from these, other specifications that are essential here include: type of material (the FDA approved material), pressure, air consumption, auxiliary machine power, weight and dimension of the machine.
I know this may seem so complicated for those of you who are new to this industry. This is why I am here to help.
Another critical aspect of roll compactor for dry granulation that is closely related to product specification is the key features.
As you’ll see shortly, this too varies depending on the design and expected functionality of the machine. Let’s review some of the key features of roll compactor machines for the pharmaceutical industry.
5. Features of Roll Compactor Machines
Pharmaceutical roll compactor machines come in a range of shapes and designs. This is the reason why these features vary from one machine to another.
Below are some of the most common features of roller compactors:
· CE and cGMP Compliant
Our roll compactor machines conform to the set standards and regulations. That is, all electrical components and related structures are designed as per the CE and cGMP standards.
Entire structure of the machine is made of stainless steel
We use the FDA approved material – this is for both the entire structure and sealing mechanism. This is the reason why our pharmaceutical roll compactors guarantee a dust free operation besides zero cross-contamination.
Ideally, they are made from high grade stainless steel. That is, we may use AISI 316 for all sections that are in contact with the product and AISI 304 for other sections.
It is easy to clean, hygienic and rust proof.
· Highly Efficient Electrical Drive
We have adopted AC variable frequency drive (VFD) for most sections of the machine. Take for instance, for precise and accurate control of the material feeding screw, we use the AC VFD.
· High Quality and Durable Rolls
Our roller compactors come with hard chrome plated rollers that are strong and durable. Moreover, you can customize every roller to meet the specific requirements of customers.
An example of roll compactor machine
At times, we may adopt the electroless nickel plating. The rolls are available in three different options, which include knurled, plain and corrugated.
· A Precisely Controlled Synchronized Mechanism and Accurate Meshing Gear Box/Coupling Mechanism
To ensure efficiency and reliability of the entire system, all coupling mechanisms are precisely done. This guarantees seamless coupling and synchronization of the rolls for a steady torque loading.
Every section is precisely fixed to prevent chances of slippage.
· Easy Cleaning and Maintenance
This is due to the modular design of the system. You can easily lift the feed screw using a hand-operated hydraulic pump.
You can dismantle the entire components of the system to clean and maintain every section of the machine.
NOTE: It is advisable to hire a technician in case you don’t have experience in repair and maintenance of toll compactors. Alternatively, you can contact us so that we can recommend trusted technicians or send our team.
Remember, doing this without proper understanding of the roll compactor machine will make your warranty invalid.
· Scrapers both on Top and Bottom Sections
The scrappers ensure no powder sticks on the surface of the rollers. Ideally, this ensures consistent dry granulation process.
· Automatic Loading of Material
At times, in situations where you intend to realize consistent and uniform loading, we may equip the machine with a vacuum transfer system.
· Enhanced Safety Features
These may include flame proof electrical components, limit switch for compaction chamber and a slip clutch at the drive. Moreover, our machines have emergency stop and overload relay.
· High Compression Force
With the robust structure of our roll compactor machines, you can get high-density products thou, this can be regulated depending on the specific requirements of your application.
As I had stated earlier, the number of features will depend on the complexity of roll compactor machine design. Remember, the advancement in technology contributes to the many features in some machines.
Having discussed all these, now let’s focus on why we consider dry granulation. This brings us to yet another fundamental aspect of roller compaction technology:
6. The Advantages and Disadvantages of Roll Compactor Machines
There is no pharmaceutical machine that is 100% perfect. It is for this reason why at times, we may adopt a wet granulation as opposed to dry granulation.
The process of dry granulation
Now, let’s review the pros and cons of roll compactor machines:
· Advantages of Roll Compactor Machines
Some of the key merits of this equipment include:
- Ensures simple material processing
The fact that you don’t require humidification makes this process simple and easy. All you need to do is feed the material via the hopper and it moves seamless down to the compaction area.
This is why as roll compactor manufacturers, we recommend this machine for moisture and heat sensitive material processing.
Therefore, it is a suitable machine for hygroscopic products such as in herbal extract. Also, you can use it for products with poor flowability such as ibuprofen.
- Help to maintain the chemical and physical properties of materials
Compacting material does not change its physical and chemical properties. Besides, it allows for fast and easy disintegration of particles.
This is because the process does not require any granulation fluid to bind the particles together.
- You can easily process high-density materials
Rollers exert a sufficient amount of force that can transform powder to the desired shape and size. With the high compression force, the machine can produce high intensity and density products.
The final product of a dry granulation process
- Hydraulic system ensures soft granulation
You can seamlessly adjust the feeding speed and compaction force. Therefore, you can adjust the force on the rolls as they rotate to ensure smooth granulation.
Remember, this will also reduce possible breakdowns of the machine that can be expensive for the entire process.
- Efficient and accurate material processing
Adopting a screw feeding mechanism ensures seamless and accurate feeding system. This roll compactor has a high performance screw system.
This is a simple, short and continuous process hence; you can adopt it for most material processing techniques.
Furthermore, you can control the feeding system, hence a highly accurate procedure.
· Disadvantages of Roller Compactor Machine
Generally, some of the main disadvantages of this machine include:
- Prone to dusty operation
Since there is no fluid or liquid, dry granulation is prone dust than wet granulation. However, the amount of dust is contained within the processing system as required by the cGMP standards.
Therefore, you may be forced to clean the machine regularly.
- Loss of workability
When adopted for tablet production in the drug manufacturing industry, the final product has low tensile strength.
Apart from this, the process does not allow for homogenous mixing of colors and it requires heavy duty equipment (compacting mechanism).
So far, I find this machine the most reliable and dependable option whenever you plan to process heat and moisture sensitive materials.
To overcome and ensure the efficiency of the overall process, there are certain aspects that you need to consider. This is what we are going to discuss in our next section.
7. Factors that Determine the Efficiency of Roll Compactors
Even though the process seems to be simple, there are a number of factors you should consider to optimize the dry granulation process. By adjusting or considering these aspects, you’ll control the quality of the final products.
Here are the key aspects you must consider:
- Roll pressure
- Material feeding rate
- Roll speed
- Type/properties of material – both physical and chemical properties
With these in mind, you can control the final product of the roll compaction process.
Now, I am sure you have learnt all the vital aspects of a roll compactor for dry granulation. I am sure with this information, we can help you source for an efficient and highly effective roll compactor machine from China.
Clearly, roll compactor machine is a suitable machine for heat and moisture sensitive products. Besides, it’s important that you consider all the 7 points from our case study/analysis because they will help you in making an informed decision.
For more information and queries, don’t hesitate to contact us.
More Sources of Information
- Pros and Cons of Roll Compaction – By Imjack Jeon
- Types of Roll Compactor – By SaintyCo
- Dry Granulation – Source: Wikipedia
- Roller Compact Design and Critical Parameters in Drug Formulation and Development – By Joshi Akash
- Overview on roll compaction/dry granulation process – Source: Research Gate
- Compaction Equipment – Source: MST