Screw Conveyor vs Chain Conveyor: Which Horizontal Conveying Equipment Fits Your Line

A TLSU/TLSG 30 screw conveyor moves 50–60 tons of grain per hour on ≤15kW of power. A TGSS32 chain conveyor moves a comparable 60–100 tons per hour of granular material at a crawling 0.3–0.6 meters per second. Both are horizontal conveying equipment, both move similar tonnage, and both show up as line items on the same feed mill quote — yet they solve different problems. This comparison lays out where a screw conveyor wins, where a chain conveyor wins, and where the material itself makes the decision for you.

The Short Answer

Use a screw conveyor for grain, meal, and powder runs under roughly 20° of incline where simple, sealed, low-maintenance transport matters most.

Use a chain conveyor for longer horizontal runs, multiple inlet and outlet points along the same line, or lighter bulk-density materials where gentle handling reduces breakage. The deciding factor is almost always bulk density and how many drop points the run needs — not raw capacity, since both types overlap heavily on tonnage.

How Each Type Moves Material

A screw conveyor uses a rotating helical screw, sometimes called an auger, turning inside a fixed trough or tube. As the screw rotates, its helical flight pushes material forward along the trough the same way a corkscrew advances through a cork — this is the term worth defining before going further, since "screw" and "auger" are used interchangeably in the industry for the same rotating flight. The TLSU and TLSG designations refer to U-shaped trough and enclosed-tube casing versions of the same working principle.

A chain conveyor — also called a drag chain or buried scraper conveyor — pulls material along an enclosed trough using flights or paddles attached to a continuous chain loop. Instead of pushing material forward with a rotating screw, the chain drags a mass of material forward in a solid, moving bed, which is why bulk density is such a critical limit for this design: too dense a material overloads the chain and drive before it overloads the motor rating.

Capacity Comparison

Both product lines scale across a wide range, and the two overlap enough in raw tonnage that capacity alone rarely decides between them.

Raw Material Fit

TGSS-series chain-driven scraper conveyor features excellent sealing performance, which effectively suppresses dust leakage and improves the workshop working environment. Equipped with wearresistant plastic liner plates for guide rails, it generates low operating noise with manageable overall maintenance workload. For these reasons, it is widely applied in the feedprocessing industry. Most feed raw materials, grains and oilseed meals satisfy this operating condition, whereas certain high-density minerals and additives are incompatible with scraper conveyors.

A screw conveyor handles a broader density range because the helical flight pushes material rather than dragging a full bed of it, but it is more sensitive to abrasive material, since abrasive particles wear the flight edge with every rotation. For highly abrasive materials at high volume, a chain conveyor's guide rail — which the TGSS series lines with a wear-resistant plastic board — often holds up longer than an exposed screw flight running at the same duty cycle.

Installation, Sealing, and Maintenance

A screw conveyor seals well by design: the enclosed tube or trough with a low-speed chain-driven screw gives good containment and is straightforward to inspect and maintain, since the moving parts are limited to the screw shaft, flight, and end bearings. This simplicity is a major reason mills default to screw conveyors for straightforward point-to-point runs.

It tolerates multiple inlet and outlet points along a single run far better than a screw conveyor does, because material can be introduced or withdrawn at intermediate gates without disrupting the drag action — a screw conveyor's flight geometry is far less forgiving of mid-run branch points.

Selection Logic and Procurement Risk

Check bulk density before anything else. Select a suitable conveying method according to material characteristics and application scenarios.

Confirm the chain conveyor's rated speed matches your process timing. All TGSS models run at a fixed 0.3–0.6m/s regardless of capacity tier — capacity scales with trough size and chain pitch, not speed .

Frequently Asked Questions

Can a screw conveyor be installed at a steep incline?

No. The TLSU/TLSG series is rated for horizontal conveying or inclines up to roughly 20°. Beyond that angle, material tends to slip back along the flight faster than it advances, so a bucket elevator is the correct choice for steep or vertical lifts.

Why does the chain conveyor's speed stay the same across all models?

The 0.3–0.6 m/s range is set by how the drag-chain mechanism handles a bulk material bed without excessive wear or spillage; larger models achieve higher capacity through a bigger trough cross-section rather than by running the chain faster.

Is a chain conveyor gentler on the material than a screw conveyor?

Generally yes, for friable materials. The wear-resistant guide rail on the TGSS series is specifically designed to reduce noise and material breakage compared with earlier scraper designs, since the material moves as a bed rather than being repeatedly pushed and sheared by a rotating flight.

Can both conveyor types be used on the same production line?

Yes, and it is common practice. A typical layout uses a screw conveyor for short, sealed transfers near mixing or batching equipment, and a chain conveyor for longer horizontal runs feeding multiple storage bins, with a bucket elevator handling any vertical lift between the two.

Written by: Yuda Machinery Engineering Team
Based on years of experience in feed machinery manufacturing, equipment design and overseas project installation.