Tubular Screw Conveyor

Tubular screw conveyors are commonly used in feed mills, flour plants, grain processing lines, premix systems and bulk material handling facilities for products such as feed ingredients, grain, flour, bran, premix, corn, wheat, barley, mineral additives, powder products and granulated raw materials.

What Is a Tubular Screw Conveyor?

A tubular screw conveyor works with a rotating screw flight inside a closed pipe-shaped body. As the screw rotates, it moves the product from the inlet point to the discharge point through the tube.

Because the product remains inside a closed body during transfer, contact with the external environment is reduced. This helps limit dust spread, product loss and exposure to wind, moisture, foreign particles and other environmental factors.

For this reason, tubular screw conveyors are often selected in production lines where powders, granules or fine bulk materials need to be transferred in a cleaner and more contained way.

Where Is a Tubular Screw Conveyor Used?

Tubular screw conveyors are used in industrial applications where enclosed transfer is required. They are especially practical for powder and granule handling lines where product containment matters.

Typical applications include:

• Feed mill conveying systems
• Flour and bran transfer lines
• Grain and premix handling
• Mineral additive transfer
• Powder and granule conveying
• Silo discharge and feeding lines
• Inclined transfer points
• Enclosed bulk material handling systems

The system can be installed in horizontal or inclined lines. In some applications, it can also be used for steeper conveying angles, but capacity, motor power and product behaviour should be evaluated carefully.

Enclosed Transfer for Powders, Granules and Bulk Materials

One of the main advantages of a tubular screw conveyor is its closed body structure. The material is carried inside the tube, which helps reduce dust spread and product spillage during transfer.

This is important in production areas where:

• Dust control is required
• Product loss should be reduced
• The material should be protected from external contamination
• The working environment needs to remain cleaner
• Powder or fine granule products are being handled

Compared with open transfer points, a closed tubular conveyor can support a cleaner and more organised production process.

Horizontal and Inclined Conveying Applications

Tubular screw conveyors are commonly used for horizontal and inclined transfer of powders, granules and fine bulk materials. In horizontal conveying, the screw flight moves the product forward through the tube in a controlled way.

When the conveyor is installed at an incline, the system must not only move the product forward but also lift it against gravity. As the incline angle increases, conveying capacity may decrease and motor power requirements may increase.

For inclined tubular screw conveyor applications, the following details should be reviewed:

• Incline angle
• Product density
• Flow behaviour
• Conveyor length
• Screw diameter
• Rotation speed
• Required motor and gearbox selection

Hourly capacity alone is not enough for a correct design. Product characteristics and installation conditions directly affect the final conveyor performance.

Diameter, Length and Drive Selection

A tubular screw conveyor should be designed according to the product, conveying distance and working conditions. Diameter, length, screw speed and motor power all affect system performance.

Screw Diameter

Screw diameter should be selected according to product particle size, bulk density, flow behaviour and required capacity.

For free-flowing fine or granular materials such as wheat, flour or similar products, a more compact screw diameter may be suitable depending on capacity and line conditions. For heterogeneous or larger-particle materials, the conveyor diameter should be reviewed more carefully because particle size, flow behaviour and blockage risk can affect operation.

Conveyor Length and Speed

Tubular screw conveyors can be manufactured in different lengths according to the project. For longer conveying distances, the design may require additional support points or a different conveyor arrangement.

In applications where fragile products are handled, conveyor length, intermediate support points and screw speed should be evaluated carefully to reduce product damage.

Free-flowing and light materials may allow higher screw speeds in suitable conditions, while heavier, abrasive or dense materials generally require a more controlled speed and stronger drive selection.

Motor and Gearbox Selection

Motor and gearbox selection depends on product density, conveying angle, required capacity, line length and operating conditions.

Light and free-flowing products such as flour, bran and grain may require less power compared with dense or abrasive materials. Heavier products, higher inclines and longer lines usually require more careful drive calculation.

The final motor and gearbox selection should be made according to project data, not by conveyor diameter alone.

Tubular Screw Conveyor vs U-Type Screw Conveyor

Tubular screw conveyors and U-type screw conveyors are both used for bulk material transfer, but their body structures and best-use cases are different.

A tubular screw conveyor has a closed pipe body. It is often preferred where product containment, dust control and enclosed transfer are important. It can also be useful in compact layouts or inclined conveying routes.

A U-type screw conveyor has a trough-shaped body with removable or hinged covers. This design provides easier access for cleaning, inspection and maintenance. It is often preferred in horizontal or low-incline lines where service access is important.

The right choice depends on product type, dust level, cleaning frequency, incline angle, hygiene requirements, capacity and plant layout.

Kardev Project-Specific Tubular Screw Conveyor Solutions

Kardev designs and manufactures tubular screw conveyor systems for powder, flour, granule and bulk material handling applications.

Each conveyor is evaluated according to product type, required capacity, line length, incline angle, plant layout and working conditions. Screw diameter, body structure, screw speed, motor-gearbox group and inlet-outlet configuration are selected according to the needs of the production line.

Kardev tubular screw conveyor systems can be designed for:

• Enclosed powder and granule transfer
• Feed, flour, bran and premix handling
• Silo discharge and controlled feeding
• Horizontal and inclined conveying lines
• Project-specific inlet and outlet positions
• Dust-controlled material transfer
• Compact installation areas
• Integration with silos, mixers, hoppers and process equipment

For production lines where dust control, product containment and safe transfer are important, a project-specific tubular screw conveyor design can provide a practical solution.

FAQ

What products can a tubular screw conveyor carry?

A tubular screw conveyor can be used for feed ingredients, grain, flour, bran, premix, mineral additives, granules and various powder products. The final design should be selected according to product density, flow behaviour, particle size, moisture level and required capacity.

What is the difference between a tubular screw conveyor and a U-type screw conveyor?

A tubular screw conveyor has a closed pipe body and is often preferred for enclosed transfer, dust control and compact conveying routes. A U-type screw conveyor has a trough body with easier access for cleaning, inspection and maintenance.

Can a tubular screw conveyor be used for inclined conveying?

Yes. Tubular screw conveyors can be used in inclined conveying lines, but the incline angle affects capacity and power requirements. Product density, flow behaviour, conveyor length and motor selection should be evaluated during the design stage.

What factors affect tubular screw conveyor capacity?

Capacity depends on screw diameter, pitch, rotation speed, filling rate, product density, conveyor length and incline angle. Product flow behaviour and operating conditions should also be considered.

Can Kardev manufacture project-specific tubular screw conveyors?

Yes. Kardev can design and manufacture tubular screw conveyors according to product characteristics, required capacity, conveying distance, incline angle, plant layout and process needs.

Request a Project-Specific Tubular Screw Conveyor Design

If you need a tubular screw conveyor for feed, flour, grain, premix, powder or granule transfer, the correct design should start with product and layout data.

Share your product type, required capacity, product density, conveying distance, incline angle and inlet-outlet positions with Kardev. Our team can evaluate the right tubular screw conveyor configuration for your production line.