Home/Products/Drag Conveyors

Bulk Material Handling Equipment

Drag ConveyorsEnclosed conveying for bulk materials

Orthman drag conveyors move grain and suitable bulk solids through an enclosed housing using a continuous chain and flights. The design provides high volumetric capacity in a compact profile while helping contain dust and minimize product degradation.

Each conveyor is engineered around the material characteristics, required capacity, conveying distance, elevation change, and equipment layout. Designed and built in Cleburne, Texas.

Request a Conveying Quote
Enclosed Conveying Enclosed housing helps contain material and reduce dust emissions
High Volumetric Capacity Efficient use of the conveyor cross-section provides high capacity in a compact profile
Gentle Handling Material degradation is minimized during transfer
Custom-engineered Housing, chain, flights, drives and wear components selected for the application

The basics

What is a drag conveyor?

An Orthman drag conveyor moves bulk material through an enclosed housing using a continuous chain fitted with flights. The conveying action and housing design are selected based on the material, capacity and severity of the application.

Round-bottom drag conveyors

Typically used for grain, feed ingredients, pellets, granules, powders and other relatively free-flowing bulk materials. The chain and flights impart motion to the material, while internal friction within the material bed helps move the product through the conveyor as a mass.

This en-masse conveying principle makes efficient use of the housing cross-section and provides relatively high volumetric capacity in a compact conveyor profile. Because the material moves as a bed with less lifting and tumbling, it can also help reduce product degradation.

Flat-bottom drag conveyors

Designed for heavier-duty applications such as cement, lime, limestone, ash, minerals and aggregates. The chain and flights positively move material along the flat conveyor floor, providing a rugged conveying method for dense, abrasive and more demanding bulk solids.

Wear liners, heavy-duty chain and reinforced construction can be incorporated where required by the application.

Round-bottom drag conveyor cross-section showing the housing, chain and sprocket, flights and speed switch
Round Bottom cross-section. The chain travels through the center of the housing with flights extending to move material through the rounded bottom. Material fills the conveying section around the chain and flights, allowing the conveyor to move a deeper bed of product rather than a thin layer along the bottom.
Flat-bottom drag conveyor cross-section showing the housing, chain and sprocket, flights and speed switch
Flat Bottom cross-section. The chain and flights travel along the flat conveyor floor, positively dragging material through the housing. The wider carrying surface provides stable material flow and is well suited for heavier, denser and more abrasive bulk materials.

Both designs use an enclosed housing to help contain material and reduce dust and spillage throughout the conveying run. Sealing, gasketing, wear protection and dust-containment features can be selected to match the material and operating environment.

  • Capacity depends on usable housing cross-section, material loading, chain speed and bulk density.
  • Horizontal and inclined conveying configurations are available, subject to material characteristics and application review.
  • Multiple inlet and discharge points allow a single conveyor to receive from or distribute material to several bins, silos or process lines.
  • Application-specific construction allows the conveyor, chain, flights and liners to be matched to general industrial or heavy-duty service.

How it works

Chain, flights and a column of material

Material enters at the inlet, is carried along the bottom of the housing by the chain and flights, and leaves through the discharge. The chain wraps the drive sprocket at the head and returns along the top to the take-up at the tail. Chain, flights, sprockets, take-up, wear surfaces, and drive components are selected around the material, capacity, conveyor length, and operating conditions.

Side view of an Orthman drag conveyor showing the take-up, drive end sprocket, discharge, housing, chain, flights, inlet and tail end sprocket

Scroll to see the full diagram

Features and components

ComponentDescriptionBenefit
Formed steel housing The structural body of the conveyor, fabricated to the required cross-section with covers and access openings. Contains material and dust in one component instead of a frame plus separate enclosure, and gives the conveyor its rigidity across the span.
Endless conveyor chain The drive element carrying the flights, selected for the load, run length and material handled. Chain rated for the actual duty, so you are not replacing an undersized component or paying to move an oversized one.
Flights Attached to the chain at set spacing; profile, material and spacing configured to the product. The right flight configuration moves the bed cleanly and reduces carry-back, protecting capacity and keeping the return run from becoming a wear problem.
Wear liners Replaceable wear surfaces in the carrying run, specified to the abrasiveness of the material. Replaceable liners can be incorporated in high-wear areas to protect the conveyor housing and extend equipment service life.
Drive and take-up assemblies Head-end drive with sprocket and reducer; tail take-up maintains chain tension. Correct tension keeps a chain conveyor running smoothly. Adjustable take-up makes chain settling a routine adjustment.
Access and inspection covers Openings placed for cleanout, chain inspection and liner replacement. Access covers and inspection openings can be located to simplify chain inspection, adjustment, cleanout, and wear-component replacement.

Applications, materials and industries

Where drag conveyors earn their place

Drag conveyors are well suited for enclosed, horizontal bulk material handling where controlled movement, dust containment and reliable operation are important. The conveyor style is selected based on the material, duty and operating environment.

Round-Bottom

Industries served

  • Grain & agriculture
  • Food processing
  • Chemical
  • Power generation

Materials handled

  • Grain
  • Meals & flours
  • Pellets & granules
  • Free-flowing bulk solids

Typical applications

  • Under-hopper and bin transfer
  • Bucket elevator feed
  • Distributing to multiple bins
  • Process equipment transfer

Round-bottom drag conveyors are typically used for lighter-duty, free-flowing materials where enclosed, efficient horizontal conveying is required.

Flat-Bottom

Industries served

  • Mining & minerals
  • Power generation
  • Aggregate
  • Heavy industrial

Materials handled

  • Cement
  • Limestone
  • Ash
  • Abrasive bulk solids

Typical applications

  • Storage bin reclaim
  • Process transfer
  • Crusher & screen feed
  • Silo transfer

Flat-bottom drag conveyors are designed for more demanding applications involving heavier, abrasive or difficult-to-handle materials where rugged construction and wear resistance are critical.

Custom-engineered solutions

Designed around your material, layout and operation

Orthman does not fit an application to a catalogue unit. Capacity, geometry and construction are specified for the job, then built in the same facility that engineered them.

Configuration & length

Housing cross-section, conveyor arrangement and overall run set by the material and the space available.

Capacity

Required throughput and bulk density drive housing size, chain speed and drive power.

Inlet and discharge locations

Positioned to match the equipment feeding and receiving the conveyor, including multiple points along the run.

Chain and flight configuration

Chain selection, flight profile, material and spacing matched to load, product and run length.

Materials of construction

Housing plate, liners and hardware specified for abrasion, moisture, temperature and sanitation requirements.

Enclosure requirements

Cover style, sealing, access openings and finish detailed for the plant environment.

Integration with your system

Designed to connect with screw conveyors, belt conveyors, bucket elevators, hoppers and gates — existing or new.

Send us the application

Material, capacity, layout and the equipment either side of the conveyor is enough for our engineers to start.

Request a Conveying Quote →

Technical specifications

Specification framework

Grouped so it is clear what is a capability the conveyor can be designed to, and what is a design consideration for your installation.

Capability range

Housing cross-section
9" to 24" — sized to capacity and material bulk density
Capacity
Up to 20,000 CFH — set by cross-section, chain speed and bulk density
Conveyor length
Up to 100 feet — set by layout, drive power and chain rating
Incline capability
Up to 30 degrees — horizontal runs and modest inclines
Materials of construction
Carbon steel and stainless steel housing; AR & UHMW replaceable wear liners

Design considerations

Chain tensioning
Tail take-up, adjustable as the chain settles
Inlets and discharges
Quantity and location per layout
Discharge gates
Manual, electric or pneumatic
Access
Inspection and cleanout openings positioned for maintenance
Finish
Applied in our dedicated on-site paint system; specification to suit the environment

Common questions

Drag conveyor FAQ

What is a drag conveyor?

A drag conveyor is an enclosed bulk material handling conveyor that moves material with a continuous chain fitted with flights. The flights engage the material inside a steel housing and move it as a single column — en masse — from the inlet to the discharge. It is also called a drag chain conveyor, en masse conveyor or chain conveyor.

How does a drag conveyor work?

Material is fed into the enclosed housing through an inlet. An endless chain carrying flights travels along the bottom of the housing and the flights push into the bed of material. Because the particles hold together through internal friction, the flights move the full cross-section rather than only the material they touch. The chain wraps a drive sprocket at the head and a take-up sprocket at the tail, returning along the top of the housing while product leaves through the discharge.

What materials can a drag conveyor handle?

Drag conveyors suit grain and free-flowing to semi-free-flowing bulk solids such as meals, flours, pellets, granules and dry powders. Abrasive materials can be conveyed when the design accounts for wear — liner selection, housing plate, chain and flight material and conveyor speed all affect service life.

Bulk density, particle size, abrasiveness, moisture and temperature determine housing size, chain selection, flight configuration and liner choice, so Orthman reviews the material before recommending a design.

What is the difference between a drag conveyor and a screw conveyor?

A screw conveyor moves material with a rotating helical flight inside a trough or tube, which shears and turns the product as it advances. A drag conveyor pulls material along as a column with a chain and flights. For a given cross-section a drag conveyor generally moves more material with less agitation, while a screw conveyor is mechanically simpler and better suited to metering, mixing, heating or cooling duties.

What is the difference between a drag conveyor and a belt conveyor?

A belt conveyor carries material on top of a moving belt, which suits long runs, lumpy material and high tonnage. A drag conveyor carries material inside an enclosed housing, which contains dust and spillage, occupies a smaller cross-section and supports multiple inlets and discharges along its length. Belt conveyors remain the better choice for very long distances and sustained inclines with coarse material.

Can drag conveyors be customized, and how do I size one?

Yes. Orthman handles engineering, design and manufacturing in Cleburne, Texas, and builds each unit around the application — housing size, length, capacity, inlet and discharge locations, chain and flight configuration, materials of construction, liners, enclosure details and finish.

Sizing starts with the material and its bulk density, the required capacity, the distance and any incline, the connection points either side, and the plant environment. Send those and our engineers will size the conveyor.

Tell us what you need to move, and where it has to go

Send your material, the capacity you need and the layout, and we will size a drag conveyor around them. If a drag conveyor is not the best answer, we will tell you which of our conveying products is — and we build those too.

650 W. Industrial Blvd., Cleburne, TX 76033 · sales@orthmanconveying.com

Request a Conveying Quote Call 682-356-6200