Feed Mill Conveying Equipment: How to Choose Between Drag Chain Conveyor, Screw Conveyor, and Belt Conveyor

Why Conveyor Selection Matters More Than It Appears

When purchasing conveying equipment, feed mills often compare only the upfront purchase cost, overlooking the operational failures and losses that can arise later — and these hidden costs frequently far exceed the initial price difference. There is no one-size-fits-all answer for equipment selection; it depends on the specific material, operating conditions, and production requirements, and the final decision is best made with the input of a qualified engineer.

Various conveying equipment in a feed mill workshop

Drag Chain Conveyor: The Sealed Workhorse for High-Volume Horizontal Transfer

A drag chain conveyor — also called a buried scraper conveyor — uses a continuous chain with evenly spaced flight bars that drag material along the bottom of a fully enclosed trough. The material is conveyed in a continuous bed rather than being lifted and dropped, which makes it gentle on granular materials and inherently dust-tight because the entire conveying path is sealed inside the housing.

This is the standard choice for horizontal transfer of grain, ground feed, and feed pellets between process stages in enclosed feed mill buildings, because it handles both powder and granular material in the same machine without modification, operates at low speed with minimal noise, and can include multiple inlet and discharge points along a single machine to serve several process connections simultaneously.

TGSS Series Capacity by Model

The TGSS series uses a plastic wear-resistant guide rail that reduces noise and material breakage compared to steel-on-steel contact, and carries a sealing specification that prevents dust emission — a practical requirement in feed mills where fine powder dust is a housekeeping, health, and fire risk. The machine is not suited for high-temperature, highly corrosive, or very high-moisture materials.

Screw Conveyor: Short-Distance Transfer of Powder and Fine Grain

A screw conveyor rotates a helical flight inside a fixed trough or tube, moving material axially from inlet to discharge. It is the simplest and most compact horizontal conveying option — there is no chain, no return run, and no flight bar assembly — and it excels at short-distance transfer of free-flowing powders and granules where the run length is limited and installation space is tight.

The TLSU/TLSG series is designed for horizontal or near-horizontal conveyance, making it suitable for feeding from a storage bin outlet to a weigh hopper, transferring ground material from hammer mill discharge to mixer inlet, or moving liquid-mixed material between process steps where a short sealed transfer is needed. The low-speed chain transmission structure provides stable, gentle material handling that avoids the particle breakage that higher-speed screw configurations can cause on fragile pellets.

TLSU/TLSG Series Capacity by Model

Screw conveyors are not suited for long runs — friction heat builds up over distance and can affect heat-sensitive ingredients or cause moisture condensation in enclosed tubes. For runs exceeding approximately 15–20 meters, a drag chain conveyor is the more appropriate choice. Screw conveyors also perform poorly on fibrous or sticky materials that wrap around the flight, and on fragile finished pellets where surface abrasion from metal contact reduces pellet durability index (PDI).

Belt Conveyor: Long-Distance Transfer Where Open Conveying Is Acceptable

A belt conveyor uses a continuous rubber or fabric belt running over head and tail pulleys to carry material on the belt surface. It is the lowest-friction, lowest-energy conveying option for horizontal and gently inclined runs, and is the correct choice for long-distance transfer — between buildings, across a site, or in outdoor installations — where the conveying path cannot be sealed and the material is robust enough to be handled in open air without dust or contamination concerns.

The TDSG series belt conveyor is suited to finished pellets and coarse grain at moderate throughput levels over distances that would make drag chain or screw conveying mechanically or economically impractical. Belt conveyors are not used for fine powders or meal in enclosed processing buildings because the open belt surface generates dust at load and discharge points that is difficult to control without extensive dust collection infrastructure.

Outdoor long-distance TDSG belt conveyor in operation

Integrating Horizontal and Vertical Conveying in a Complete Feed Mill

A complete feed mill conveying system combines vertical transfer (bucket elevator) with horizontal transfer (drag chain, screw, or belt) at every stage of the process flow.

Yuda Machinery supplies the complete conveying equipment range — TDTG bucket elevators in carbon steel, galvanized, and stainless steel variants; TGSS drag chain conveyors; TLSU/TLSG screw conveyors; and TDSG belt conveyors — as part of complete feed production line projects covering plant layout, equipment sizing, manufacturing, installation, and commissioning. Specifying conveying equipment from a single supplier ensures consistent flange dimensions, control integration, and after-sales support across all transfer points in the line. Visit the conveying equipment product page for the full range and specifications.

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