Principal of double cone blender
The principle of a double cone blender is based on the concept of tumbling motion and gentle blending. The blender consists of two conical-shaped vessels joined at their bases, forming a V-shaped chamber. The vessels are mounted on a central shaft, which is connected to a motor that rotates the vessels.
Inside the vessels, there are blades or paddles attached to the shaft, which help in mixing the materials. The conical shape of the vessels and the rotating motion of the blades create a tumbling action, ensuring thorough mixing of the materials.
The design of the double cone blender allows for gentle blending, making it suitable for delicate materials and those with varying particle sizes. The blender is also designed to minimize the risk of material segregation, ensuring a homogeneous mixture.
Basic principle of a double cone blender or Double cone mixer is to provide efficient and gentle blending of powders and granules, ensuring the homogeneity of the mixture.
Construction of double cone blender
The construction of a double cone blender involves several key components, each designed to ensure efficient and effective blending of powders and granules. Here’s a detailed look at the construction of a double cone blender:
1. Vessels: The blender consists of two conical-shaped vessels joined at their bases, forming a V-shaped chamber. These vessels are typically made of stainless steel, which is known for its durability, resistance to corrosion, and ease of cleaning. The vessels are designed to hold a specific volume of material, known as the blender’s capacity. The capacity of a double cone blender can vary widely depending on the size and design of the blender. Smaller laboratory-scale double cone blenders may have capacities ranging from a few liters to around 20 liters, while larger industrial-scale double cone blenders can have capacities ranging from 50 liters to several thousand liters.
2. Shaft and Blades: Inside the vessels, there is a central shaft that runs the length of the blender. This shaft is connected to a motor that rotates the vessels. Attached to the shaft are blades or paddles that help in mixing the materials. The blades are strategically positioned to create a tumbling motion, ensuring thorough blending. The blades are typically made of stainless steel or other materials that are resistant to corrosion and can withstand the rigors of industrial use.
3. Motor and Drive Mechanism: The motor is responsible for rotating the vessels and driving the blades. It is typically located outside the vessels and is connected to the shaft via a drive mechanism, such as a belt or gear system. The motor and drive mechanism are designed to provide the necessary power and torque to ensure efficient blending.
4. Valves: The blender is equipped with a discharge valve at the bottom of the vessels that allows for the removal of the blended mixture. The valve is typically a butterfly valve, which consists of a disc that rotates around a central shaft to control the flow of material. When the valve is closed, the disc is perpendicular to the flow, blocking the passage of material. When the valve is open, the disc is parallel to the flow, allowing the material to pass through.
Butterfly valves are commonly used in industrial applications due to their simple design, ease of operation, and ability to provide a tight seal. Additionally, some double cone blenders are equipped with a vacuum valve, which allows for the creation of a vacuum inside the vessels. This can be useful for certain applications, such as drying or deaerating materials.
5. Support Structure: The blender is supported by a sturdy frame or base that provides stability during operation. This support structure is often made of steel or other durable materials.
6. Safety Features: Some double cone blenders are equipped with safety features, such as interlocks and emergency stop buttons, to ensure safe operation.


Capacity : double cone mixer capacities varies from few L to 3000 L, based on requirements.
Ideal construction of a double cone blender should involves the use of materials that are resistant to corrosion, durable, and easy to clean, ensuring the longevity and efficiency of the blender. Argon arc welding used for welding purpose.
Working Procedure of Double Cone Mixer
These are the working procedure for a double cone blender:
1. Loading:
- Open the loading lid: Locate the loading aperture or lid on one end of the blender.
- Fill the blender: Carefully pour the desired amount of powder or granules into the blender, ensuring it doesn’t exceed 2/3rds of the total volume. Overfilling can hinder proper mixing.
- Close the lid securely: Ensure the lid is properly fastened to prevent spillage during operation.
2. Setting up:
- Power connection: Connect the blender to a power source based on the electrical specifications of the model.
- Rotation speed adjustment :Some blenders offer adjustable rotation speeds. Consult the manufacturer’s instructions for the recommended speed for your specific application.
3. Blending:
- Start the blender: Turn on the power switch or press the start button, depending on the model.
- Mixing time: The typical mixing time for most dry materials ranges from 5 to 15 minutes. However, this can vary depending on the material properties, desired level of homogeneity, and blender size.
- Monitoring: It’s recommended to visually monitor the blending process to ensure proper mixing and identify any potential issues like uneven distribution.
4. Discharging:
- Stop the blender: Once the desired mixing time is reached, turn off the power or press the stop button.
- Open the discharge valve: Locate the butterfly valve or discharge port at the opposite end of the blender from the loading lid. Open it carefully to allow the mixed material to flow out.
- Collect the material: Collect the blended material in a suitable container positioned beneath the discharge opening.
5. Cleaning :
- Switch off and unplug: Before cleaning, always ensure the blender is turned off and disconnected from the power source.
- Emptying: Remove any residual material from the blender chamber.
- Cleaning: Depending on the material being mixed and the desired level of cleanliness, various cleaning methods can be used, such as wiping with a dry cloth, brushing, or using a vacuum cleaner. Some models might allow for wet cleaning with specific solutions (consult the manual).
- Drying: Ensure the blender is completely dry before storing it to prevent moisture build-up and potential rusting.
Precautions & notes during handling procedure:
- Safety precautions: Always follow the manufacturer’s safety instructions for your specific double cone blender model. This may include wearing safety glasses and gloves while operating the blender.
- Material compatibility: Ensure the material you are blending is compatible with the blender’s construction materials. Some materials might require specific cleaning procedures to avoid reactions or contamination.
- Calibration & Preventive Maintenance : Certain models might require periodic calibration & maintenance to ensure accurate rotation speed and mixing performance. Refer to the manufacturer’s recommendations for calibration procedures and frequency.
Uses double cone blender (DCB):
- The double cone blender (DCB) is a versatile and efficient mixing device used in various industries, including pharmaceuticals, food, chemicals, and cosmetics. Its unique design, with conical shapes at both ends and a ‘slant’ design, allows for uniform mixing and easy discharge of materials.
- DCBs can be used to mix dry powders or granules into tablets and capsule formulations. They are also used to mix dry granules sublots in bulk lubrication stages of tablet granules to increase the batch size.
- Additionally, wet powder to dry powder mixing can be performed with this equipment.
- The DCB mixer blender is well suited for mixing granular and powdery materials with excellent mixing quality.
- It can be used in chemical, plastic, rubber, food, essence, dye, and dyeing industries.
- In general, it is used for medical intermediates, flavorings, graphite, coffee powder, iron powder with a specific gravity less than 7 grams per cubic centimeter that has some fluidity with no liquid content greater than 10%.
Advantages of Double Cone Blender:
1. Gentle Blending: The tumbling motion created by the conical shape of the vessels and the rotating blades ensures gentle blending, making it suitable for delicate materials and those with varying particle sizes.
2. Uniform Mixing: The design of the double cone blender ensures thorough mixing of materials, resulting in a uniform blend.
3. Versatility: Double cone blenders can be used for a wide range of applications, including blending powders, granules, and dry ingredients.
The double cone blender (DCB) is a versatile and efficient mixing device used in various industries, including pharmaceuticals, food, and chemicals. Its unique design, with conical shapes at both ends and a ‘slant’ design, allows for uniform mixing and easy discharge of materials. The close-container design ensures good product rolling and cross-mixing, resulting in a homogeneous blend.
4. Easy to Clean: The stainless steel construction of double cone blenders makes them easy to clean, ensuring hygiene and preventing cross-contamination.
5. Adjustable Speed: The speed of the blender can be adjusted to suit the specific requirements of the materials being blended.
6. Safety Features & other: Some double cone blenders are equipped with safety features, such as interlocks and emergency stop buttons, to ensure safe operation.
The DCB mixer blender is also designed with safety in mind. The conical shapes at both ends of the blender help to statically balance the cone, preventing excessive loads from damaging the gearbox or motor. Additionally, paddle type baffles can be added to the shaft for better mixing, depending on the characteristics of the product being blended.
7. Maintenance: The DCB mixer blender is designed to handle a wide range of materials, from powders to granules, and can even de-agglomerate materials. The use of stainless steel (S.S.304 and S.S.316) in contact parts prevents corrosion and contamination, ensuring the quality and purity of the final product.
Disadvantages of Double Cone Blender:
1. Limited Capacity: The capacity of a double cone blender is limited by the size and design of the blender, making it unsuitable for large-scale production.
2. Material Segregation: Despite the tumbling motion, there is still a risk of material segregation, especially with materials of different densities.
3. Complex Design: The design of a double cone blender is more complex compared to other types of blenders, which can make maintenance and repairs more challenging.
4. High wInitial Cost: Double cone blenders can be more expensive to purchase compared to other types of blenders.
5. Limited Control Over Mixing: The tumbling motion of the double cone blender may not provide as much control over the mixing process compared to other types of blenders.
6. Limited Applications: Double cone blenders are primarily used for blending dry materials and may not be suitable for all types of materials or applications.
The advantages of double cone blenders, such as gentle blending, uniform mixing, and versatility, make them a popular choice for many industries. However, it is important to consider the limitations and disadvantages of double cone blenders when selecting a blender for a specific application.
Disadvantages of Double Cone Blender:
- Limited Capacity: The capacity of a double cone blender is limited by the size and design of the blender, making it unsuitable for large-scale production.
- Material Segregation: Despite the tumbling motion, there is still a risk of material segregation, especially with materials of different densities and fine particles.
- Complex Design: The design of a double cone blender is more complex compared to other types of blenders, which can make maintenance and repairs more challenging.
- High Initial Cost: Double cone blenders can be more expensive to purchase compared to other types of blenders.
- Limited Control Over Mixing: The tumbling motion of the double cone blender may not provide as much control over the mixing process compared to other types of blenders.
- Limited Applications: Double cone blenders are primarily used for blending dry materials and may not be suitable for all types of materials or applications.
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