Indented Cylinder Separator for Seeds & Grain

Indented Cylinder Separator for Accurate Seed and Grain Length Grading

The ADDAMS Indented Cylinder Separator grades seeds, grains, pulses and other free-flowing products according to particle length. It is used to remove broken kernels, short seeds or elongated impurities that cannot be separated efficiently by width- and thickness-based screening.

In a complete cleaning line, screens classify material according to cross-sectional dimensions. An indented cylinder adds a different separation principle: it compares particle length. This makes the machine especially useful when the acceptable product and the unwanted material have similar width and thickness but different longitudinal dimensions.

How an Indented Cylinder Separator Works

The machine contains a rotating cylinder whose inner surface is covered with precisely formed pockets, known as indents. Product enters the cylinder and moves through the rotating working section. Particles that fit inside the indents are lifted as the cylinder turns. At a selected release point, they fall into an adjustable internal collection trough and are conveyed to a separate outlet.

Particles that are too long to fit securely into the selected indents remain in the lower part of the cylinder and travel toward the main discharge. The separation result therefore depends on the relationship between particle length, indent size, rotational speed, feed rate and the position of the collection trough.

Short-Product Separation

When the indents are selected to capture broken or short particles, the short fraction is lifted into the trough while the longer main product continues through the cylinder. This arrangement is commonly used to remove broken wheat, short rice kernels or undersized seed pieces.

Long-Product Separation

The process can also be configured so that the desired product is lifted by the indents while longer contaminants remain in the cylinder. This is useful for removing long seeds, stalk pieces, elongated weed seeds or other admixtures from a shorter main product.

Typical Applications

• Wheat and barley: removal of broken kernels, oats or elongated foreign material.
• Rice: separation of broken rice from whole kernels and grading by kernel length.
• Oats: separation from shorter cereals or contaminants where size overlap makes screening difficult.
• Maize: classification of selected kernel fractions where length difference is a useful criterion.
• Pulses: removal of broken lentils, peas, beans or chickpeas after preliminary cleaning and grading.
• Seed production: improvement of seed-lot uniformity by removing short, broken or off-type particles.
• Speciality products: length grading of suitable granular food, feed and agricultural materials.

Performance should be confirmed against the actual product whenever particles are unusually shaped, sticky, fragile or highly variable.

Main Advantages of the ADDAMS Indented Cylinder

• True length-based grading: performs a separation that conventional flat or drum screens cannot achieve on their own.
• Interchangeable cylinder segments: indent dimensions can be selected for the crop and target separation.
• Adjustable collection trough: trough position helps define the release point and control the balance between recovery and reject quality.
• Controllable rotational speed: optional variable-frequency control allows the lifting and release behaviour to be adjusted for different products.
• Gentle product movement: controlled rotation supports the handling of valuable seeds and food products without aggressive impact.
• Inspection access: accessible covers and viewing points support observation, cleaning and routine maintenance.
• Flexible plant integration: the machine can be supplied as a single processing stage or combined with other ADDAMS cleaning and grading equipment.
• Multiple separation duties: two or more cylinders can be arranged in sequence when both short and long impurities must be removed.

Typical Technical Configuration

Feature	Typical Configuration
Separation principle	Particle-length grading using precision-formed indents
Working cylinder	Segmented shell with crop-specific round or teardrop indent patterns
Product range	Indent selections may cover approximately 1–24 mm, subject to product testing
Drive	Geared motor with optional variable-frequency speed control
Collection system	Adjustable internal trough with separate discharge conveying
Inspection	Access covers and viewing areas for process monitoring and cleaning
Safety	Guarded rotating components and project-specific safety switches
Capacity	Selected according to crop, separation duty, indent size and required purity

Final dimensions, motor power, cylinder configuration and capacity are confirmed for each application. Published or quoted throughput is always dependent on product characteristics and the required separation result.

Where the Machine Fits in a Processing Line

An indented cylinder is normally installed after preliminary cleaning and size grading. A pre-cleaner removes large and small impurities, while a fine screen cleaner creates more uniform size fractions. A de-stoner can remove stones and heavy mineral material, and a gravity separator can classify particles by density.

Once these earlier stages have created a consistent feed, the indented cylinder separates by length. The cleaned product may then proceed to an optical color sorter, seed treater, storage system or packing line. Correct process order improves accuracy and prevents excessive load on the length-grading stage.

Single, Double and Multi-Cylinder Arrangements

A single cylinder can perform one defined length separation. Where both short and long impurities are present, two cylinders can be arranged in sequence. The first stage may remove short material and the second may remove long admixtures, or the sequence may be reversed according to the product and process objective.

Selecting the Correct Indent Size

Indent selection is the central engineering decision. If the pockets are too small, the target short fraction may not be lifted effectively. If they are too large, acceptable product may enter the trough and reduce recovery. Product length distribution should therefore be measured using representative samples rather than selected only from a crop name.

For a reliable recommendation, customers should provide:

• Product type and variety
• Required hourly capacity
• Length range of the desired product
• Description and proportion of short and long impurities
• Moisture content and bulk density, when available
• Required purity and acceptable product loss
• Details of upstream screening and downstream equipment

Sample testing is particularly valuable when the product contains several overlapping fractions or when export, food-grade or certified-seed requirements apply.

Operating Adjustments

Separation quality is influenced by feed rate, cylinder speed and trough position. A high feed rate may reduce the opportunity for individual particles to enter the indents. Excessive speed can carry material beyond the preferred release point, while insufficient speed may not lift the selected fraction high enough.

During commissioning, settings are adjusted while samples are taken from each outlet. The operator should evaluate both product recovery and reject quality. A very clean reject stream may indicate that valuable product is being lost, while high contamination in the clean stream may require a different trough position, speed or indent selection.

Cleaning and Maintenance

Indent surfaces must remain clean and unobstructed. Dust, sticky residue or lodged particles can reduce pocket capacity and change separation performance. Routine inspection should include the cylinder segments, trough, internal conveyor, bearings, drive components, guards and discharge connections.

Optional Features and Plant Integration

Project options may include alternative indent patterns, variable-speed drives, different trough arrangements, inspection windows, aspiration connections, access platforms, product sampling points and integration with automatic line controls. Inlet and outlet connections can be coordinated with elevators, conveyors and buffer bins.

Frequently Asked Questions

What is the difference between an indented cylinder and a screen cleaner?

A screen cleaner separates mainly by width and thickness. An indented cylinder separates by length. The two machines complement each other and are normally used at different stages of the cleaning process.

Can the machine remove broken grain?

Yes. With the correct indent size, broken or short kernels can be lifted into the collection trough while whole, longer kernels remain in the cylinder. The exact result depends on the length distribution of the product.

Can it remove oats from wheat?

Length grading is commonly used where oats or other elongated material must be separated from shorter wheat kernels. Product samples should be tested because varieties and kernel dimensions can overlap.

Why is the collection trough adjustable?

The trough position determines where lifted particles are collected after leaving the indents. Adjusting it changes the separation boundary and helps balance purity against recovery.

Can one cylinder process different crops?

Yes, provided suitable cylinder segments and operating settings are available. Different crops may require different indent dimensions, speeds and trough positions.

How is capacity determined?

Capacity depends on cylinder size, product characteristics, feed consistency, indent selection and the required separation accuracy. ADDAMS confirms the machine configuration after reviewing the application data or product sample.

Request an Indented Cylinder Recommendation

Send ADDAMS your crop, length distribution, required capacity, impurity description and target quality. Our process engineering team can recommend the cylinder configuration, indent size and line arrangement for your application.

Related Equipment and Process Options

Combine length grading with size preparation and any separately required density or visual separation.

• Fine Seed Cleaners
• Optimum 220 Series Screen Grader
• De-Stoner Pressure Type
• Multi-Fan Gravity Separator for Seeds & Grain
• Optical Color Sorter Machine for Seeds & Grain

Share your product sample, target capacity, quality requirements and existing line layout. Request your custom quote from ADDAMS to evaluate equipment selection and process connections.